Muon Spin Relaxation Functions
|
|
- Deirdre Shields
- 5 years ago
- Views:
Transcription
1 Muon Spin Relaxation Functions Bob Cywinski Department of Physics and Astronomy University of eeds eeds S 9JT Muon Training Course, February 005
2 Introduction Positive muon spin relaxation (µsr) is a point-like magnetic probe in real space - similar to NMR and ESR, but probing time-space rather than frequency-space The time evolution of the muon spin in µsr can be measured in ero applied magnetic field via the radioactive decay of the muon - NMR and ESR measurements are generally performed in high applied fields and resonating RF fields In this lecture we shall look at muon spin relaxation under typical conditions in both ero field and applied field, and in the presence of fluctuating internal fields
3 Muon implantation Implantation is rapid and occurs without loss of muon polarisation Each muon spin therefore starts its time evolution with an initial spin polarisation of 100% The average spin polarisation of an ensemble of muons at time t after implantation is defined as the muon spin relaxation function, G(t) ~1-3 mm
4 Muon decay ifetime:.19714µs Decay asymmetry: W(θ) 1+a 0 cosθ a o ~0.5 Gyromagnetic ratio: x10 8 xπ s -1 T -1
5 Measuring the relaxation process F(t) R(t) F(t) + B(t) B(t)
6 Relaxation... µ % ]Ã RU% ) % R F(t) B(t) (t) F(t) + B(t) a o G (t)
7 Muon precession A individual muon at any specific site will generally experience a finite magnetic field along an arbitrary (-) direction The expectation values of the muon spin along the x and y directions, <S x > and <S y >, will precess at the armor frequency, ω. <S > is time independent In a sample without long range magnetic order, the magnetic field varies in both direction and magnitude from site to site. So, for ensemble of muons distributed over many sites we must account for a distribution of armor frequencies
8 Muon depolarisation in a static gaussian field distribution The local internal field responsible for the muon spin precession at each muon site originates from a dipolar interaction with surrounding nuclear or electronic spins (and contact hyperfine fields from the spin density at the muon site) For a concentrated system of randomly oriented static nuclear dipoles the probability distributions of the x, y and components of resultant internal fields, P(B i ) are Gaussian: G 1 P (H i) exp( Bi ) ( i x,y,) ) π Similarly the distribution of the magnitudes of the internal fields 3 ( ) G 1 P (H) exp B 4πB π
9 Gaussian fields 0.5 Probability distribution of x,y and components of internal field B i P(H i ) ix,y, mT Internal field, H i, ix,y, (mt) Probability distribution of the magnitude of the internal field B P( H ) mT Internal field H, mt
10 Precession in Gaussian fields: R(t)cos(γ µ Bt)
11 Relaxation in Gaussian fields: If we assume at t0 all muons are polarised along the - direction, then on average 1/3 will sense a net field directed along the x-, the y- and the -directions The 1/3 sensing a field along the -direction will not precess Averaged over all muons the resulting relaxation function is: x x1/3 y x1/3 x1/3
12 Relaxation in Gaussian fields θ cos θ sin θ µ B The -component of the muon spin polarisation s (t) has a time-independent component, proportional to cos θ and a sin θ component precessing at a frequency γ µ B s (t) cos θ + sin θcos( γ µ The relaxation function is given by the statistical average of s (t) G (t) s (t)p(b x )P(B y )P(B )db giving, for a Gaussian field distribution, the famous static Gaussian Kubo-Toyabe function : G G (t) (1 σ 3 t )exp x db y 1 ( σ t ) db (eg Hayano et al PRB 0 (1979) 850) Bt) ( γ ) σ µ
13 Relaxation in Gaussian fields and an external field If an external magnetic field, B ext, is applied along the -axis, B i should be replaced by B + B ext before the statistical average is taken: G σ 1 G (t, ω ) 1 ( 1 cos( ωt)exp( σ t )) ω σ + 3 ω 4 t 0 sin( ω τ)exp 1 ( σ τ ) dτ with ω γ µ B ext Note that this calculation assumes that the external field does not reorient the dipoles which give rise to the internal fields at the muon sites
14 Relaxation in Gaussian fields and an external field Tσt
15 Relaxation in Gaussian fields and an external field If an external magnetic field, B ext, is applied along the -axis, B i should be replaced by B + B ext before the statistical average is taken: G σ 1 G (t, ω ) 1 ( 1 cos( ωt)exp( σ t )) ω σ + 3 ω 4 t 0 sin( ω τ)exp 1 ( σ τ ) dτ with ω γ µ B ext Note that this calculation assumes that the external field does not reorient the dipoles which give rise to the internal fields at the muon sites Note also that in the absence of an external field and for a unique internal field of magnitude B the directional average gives 1 G (t) cos( γ µ B t) 3 3
16 orentian field distributions Whilst Gaussian field distributions are appropriate for concentrated dipole moments, the field distribution for dilute dipole moments is better described by the orentian function 1 Λ P (H) i ( i x,y,) ) π Λ + B ( ) Taking a statistical average over the time-dependent - component of the muon spin then gives the static orentian Kubo Toyabe relaxation function i (t) G (1 at)exp( at) with aγ µ Λ Tat
17 orentian fields and an external field Again, with an external magnetic field, B ext, applied along the -axis, B i should be replaced by B + B ext before the statistical average is taken: G (t, ω a ) 1 ω a ω 1+ (j ( ω t)exp a ω j ( ω t)exp 1 o a t 0 ( at ) ( at ) 1) (j ( ω t)exp o ( at) dτ where j o and j 1 are spherical Bessel functions: j o ( ω t) sinω ω t t, j ( ω t) 1 sinωt ( ω t) + cosωt ω t
18 orentian fields and an external field Tat
19 Intermediate field distributions Whilst the Gaussian and orentian field distributions adequately describe the concentrated and dilute dipole moment limits respectively, the distiction between the two limits is rather arbitrary We can see that the ero field Kubo Toyabe rlaxation function can be generalised as (t) G 1 3 (1 ( λt) 3 α )exp( ( λt) α α) where >α>1 Crook and Cywinski showed that this generalisation interpolates between the concentrated and dilute limits, and corresponds to P(B i ) being Voigtian distributed Crook and Cywinski J Phys Condensed Matter 9 (1997) 1149
20 Dynamic muon spin relaxation functions Internal field dynamics, resulting either from the muon hopping from site to site or from the internal fields themselves fluctuating, can be accounted for within the strong collision approximation, ie it is assumed that the local field changes its direction at a time t according to a probability distribution p(t)exp(-νt), the field after such a collision is chosen randomly from the distribution P(B i ) and is entirely uncorrelated with the field before the collision
21 The strong collision model -fast fluctuations exp(-λt) σ0.1 µs -1 G (t) time (µs) The above curves have been calculated assuming that ν/σ5 This is within the fast fluctuation (motional narrowing) limit for which the relaxation envelope is well described by exp(-λt)
22 Dynamic relaxation The total muon polarisation at time t is the superposition of the polarisation of each muon at that time. So, the fraction that have not experienced a field change at time t is given by exp(-νt), and their contribution is g (0) (t) g (t) e A particular muon that has experienced one change at time t has a probability of remaining stationary until the further time t of exp(-ν(t-t )). The contribution to the total polarisation from all muons having had only one jump to time t is thus g (1) (t) ν 0 g (t )e νt νt ν( t t ) g (t t )e dt The higher order terms can be successively derived by the recurrence relation g (n) (t) ν t 0 g (0) (t )g (n 1) (t t )dt
23 Dynamic relaxation (cont( cont.) The total muon relaxation function can be written as the sum over all n of g (n) (t) G DKT (t) g g 0 (0) (0) g (n) (t) + (t) n 1 (t) + ν t 0 ν t 0 G g DKT (n 1) (t t ) g (t t ) g (0) (0) (t )dt (t )dt This expression can be evaluated by numerical integral for any internal field distribution (ie Gaussian, orentian* or Voigtian) with or without an external applied field The result is the dynamic Kubo-Toyabe function (eg Hayano et al PRB 0 (1979) 850)
24 Dynamic Gaussian Kubo-Toyabe function 1.0 R R0 0.6 R10 G DKT (t) R R R1 R0 R T The dynamic Kubo-Toyabe function plotted as a function of the dimensionless parameters, Tσt and Rν/σ. For R>1 approximate forms for G DKT (t) can be used
25 Dynamic Gaussian Kubo-Toyabe function in an applied longitudinal field Tσt
26 Some approximations For a gaussian field distribution in the fast fluctuation limit (Rν/σ>>1) in ero field G (t) exp( σ t ν) exp( λt) whilst in an applied field σ τc λ τc 1/ ν (1+ ω τ ) c For a gaussian field distribution in the intermediate fluctuation limit (Rν/σ>1) in ero field we have the so-called Abragam form σ t G(t) exp (exp( νt) 1+ νt) ν For very slow fluctuations R<1 only the 1/3 Kubo-Toyabe tail is affected. The form of this tail becomes G G (t, ν) 1 exp( (/ 3) νt) 3
27 Dynamic orentian Kubo-Toyabe function *Note that for the orentian case a hopping muon and fluctuating fields do not necessarily give the same result
28 Special cases: dilute magnetic alloys Uemura (PRB31 (1985) 546) assumed that the fluctuation of magnetic impurity moments in dilute spin glasses leads to a time modulated field at the muon site. The dynamic range of this field modulation will depend on the proximity of the muon to its neighbouring spins µ + Au P(H) The dynamic variable range of the local fields at each muon site is approximated by a Gaussian distribution of width σ/γ µ, G γ µ γµ Bi P (B i) exp σ π σ Fe, i H P(H) µ + H x, y,
29 dilute magnetic alloys (cont( cont) The probability, ρ(σ j ), of choosing a muon site j for which the width of the dynamic range is σ j must satisfy the condition G P (B ) P (B, σ ) ρ( σ )dσ i 0 where P (B i ) is the original orentian field distribution Uemura showed that ρ( σ j ) (a π σ i j ) exp( a Assuming the fast fluctuation limit with a unique fluctuation rate ν we calculate G (t,a, ν) 0 G G j j σ (t, σ, ν) ρ( σ)dσ Hence, in the fast fluctuation limit, we find the root-exponential form G (t,a, ν) exp 4a t ν ( ) )
30 Distributed relaxation rates In many spin glasses the relaxation function is found to be not root-exponential but stretched exponential β G (t) exp( ( λt) ) Moreover, β itself is temperature dependent often decreasing from 1 at high temperatures (4T g ) to 1/3 at T g Ag-5at%Mn b T g T g Campbell, et al PR 7 (1994) 191 (eg Ogielski PRB 3 (1985) 7384) Whilst the muon relaxation is measured in aplace time, this functional form mirrors exactly the Kohlrausch relaxation predicted theoretically for spin-spin correlations in real time
31 Distributed relaxation rates This behaviour can be modeled quite simply by assuming the rapid fluctuation limit but with a broad distribution of muon spin relaxatio rates, P(λ), so G(t) 0 P( λ)e λ t d We find that for any (broad) P(λ) leads to the form λ β ( ( λt ) G (t) exp ) As P(λ) becomes extremely broad (as predicted for a spin glass approaching T g ) β approaches 1/3 asymptotically. Cywinski et al (unpublished)
32 Rotation. µ %[Ã! ) % R x (t) F(t) F(t) + B(t) B(t) a o G x (t) cos( ω t)
33 Transverse field µsr In a high applied fields B T transverse to the initial muon spin (-)direction, the muons will precess around the vector sum of B T and the internal field B For a Gaussian internal field distribution for which B T >>, the direction of the local field is almost parallel to B T In this situation the magnitude of the field at the muon site is approximately B T + B i where i is the component in the field direction (say ix) The muon precession is therefore of the form R(t) cos( ωtt)exp( σ t / ) and G G (t) exp( σ t / ) x Note that nuclear dipoles may also precess in an applied field thereby reducing the effective s by a factor of 5 compared to ero field
Spin Relaxation and NOEs BCMB/CHEM 8190
Spin Relaxation and NOEs BCMB/CHEM 8190 T 1, T 2 (reminder), NOE T 1 is the time constant for longitudinal relaxation - the process of re-establishing the Boltzmann distribution of the energy level populations
More informationComplementarity: muons and neutrons
Complementarity: muons and neutrons Sue Kilcoyne Salford M5 4WT What can neutrons tell us? Neutrons: have wavelengths comparable to interatomic spacings (0.3-15 Å) have energies comparable to structural
More informationIntroduction to Relaxation Theory James Keeler
EUROMAR Zürich, 24 Introduction to Relaxation Theory James Keeler University of Cambridge Department of Chemistry What is relaxation? Why might it be interesting? relaxation is the process which drives
More informationThe Positive Muon as a Probe in Chemistry. Dr. Iain McKenzie ISIS Neutron and Muon Source STFC Rutherford Appleton Laboratory
The Positive Muon as a Probe in Chemistry Dr. Iain McKenzie ISIS Neutron and Muon Source STFC Rutherford Appleton Laboratory I.McKenzie@rl.ac.uk µsr and Chemistry Properties of atoms or molecules containing
More informationNMR Dynamics and Relaxation
NMR Dynamics and Relaxation Günter Hempel MLU Halle, Institut für Physik, FG Festkörper-NMR 1 Introduction: Relaxation Two basic magnetic relaxation processes: Longitudinal relaxation: T 1 Relaxation Return
More informationT 1, T 2, NOE (reminder)
T 1, T 2, NOE (reminder) T 1 is the time constant for longitudinal relaxation - the process of re-establishing the Boltzmann distribution of the energy level populations of the system following perturbation
More informationμsr Studies on Magnetism and Superconductivity
The 14 th International Conference on Muon Spin Rotation, Relaxation and Resonance (μsr217) School (June 25-3, 217, Sapporo) μsr Studies on Magnetism and Superconductivity Y. Koike Dept. of Applied Physics,
More informationDynamics as probed by muons
Dynamics as probed by muons P. Dalmas de Réotier and A. Yaouanc Institut Nanosciences et Cryogénie Université Grenoble Alpes & CEA Grenoble, France. 13th PSI Summer School on Condensed Matter Research
More informationFrequency- and Time-Domain Spectroscopy
Frequency- and Time-Domain Spectroscopy We just showed that you could characterize a system by taking an absorption spectrum. We select a frequency component using a grating or prism, irradiate the sample,
More informationNMR, the vector model and the relaxation
NMR, the vector model and the relaxation Reading/Books: One and two dimensional NMR spectroscopy, VCH, Friebolin Spin Dynamics, Basics of NMR, Wiley, Levitt Molecular Quantum Mechanics, Oxford Univ. Press,
More informationGeneral NMR basics. Solid State NMR workshop 2011: An introduction to Solid State NMR spectroscopy. # nuclei
: An introduction to Solid State NMR spectroscopy Dr. Susanne Causemann (Solid State NMR specialist/ researcher) Interaction between nuclear spins and applied magnetic fields B 0 application of a static
More informationBiophysical Chemistry: NMR Spectroscopy
Relaxation & Multidimensional Spectrocopy Vrije Universiteit Brussel 9th December 2011 Outline 1 Relaxation 2 Principles 3 Outline 1 Relaxation 2 Principles 3 Establishment of Thermal Equilibrium As previously
More informationJoint Project between Japan and Korea M. Jeong, M. Song, S. Lee (KAIST, Korea) +KBSI T. Ueno, M. Matsubara (Kyoto University, Japan)+Fukui Univ.
Joint Project between Japan and Korea M. Jeong, M. Song, S. Lee (KAIST, Korea) +KBSI T. Ueno, M. Matsubara (Kyoto University, Japan)+Fukui Univ. +Vasiliev(Turku) 31 P NMR at low temperatures ( down to
More informationBiophysical Chemistry: NMR Spectroscopy
Spin Dynamics & Vrije Universiteit Brussel 25th November 2011 Outline 1 Pulse/Fourier Transform NMR Thermal Equilibrium Effect of RF Pulses The Fourier Transform 2 Symmetric Exchange Between Two Sites
More informationChemistry 431. Lecture 23
Chemistry 431 Lecture 23 Introduction The Larmor Frequency The Bloch Equations Measuring T 1 : Inversion Recovery Measuring T 2 : the Spin Echo NC State University NMR spectroscopy The Nuclear Magnetic
More informationClassical Description of NMR Parameters: The Bloch Equations
Classical Description of NMR Parameters: The Bloch Equations Pascale Legault Département de Biochimie Université de Montréal 1 Outline 1) Classical Behavior of Magnetic Nuclei: The Bloch Equation 2) Precession
More informationClassical Description of NMR Parameters: The Bloch Equations
Classical Description of NMR Parameters: The Bloch Equations Pascale Legault Département de Biochimie Université de Montréal 1 Outline 1) Classical Behavior of Magnetic Nuclei: The Bloch Equation 2) Precession
More informationSlow symmetric exchange
Slow symmetric exchange ϕ A k k B t A B There are three things you should notice compared with the Figure on the previous slide: 1) The lines are broader, 2) the intensities are reduced and 3) the peaks
More informationSpectral Broadening Mechanisms
Spectral Broadening Mechanisms Lorentzian broadening (Homogeneous) Gaussian broadening (Inhomogeneous, Inertial) Doppler broadening (special case for gas phase) The Fourier Transform NC State University
More informationElectron spins in nonmagnetic semiconductors
Electron spins in nonmagnetic semiconductors Yuichiro K. Kato Institute of Engineering Innovation, The University of Tokyo Physics of non-interacting spins Optical spin injection and detection Spin manipulation
More informationMagnetic domain theory in dynamics
Chapter 3 Magnetic domain theory in dynamics Microscale magnetization reversal dynamics is one of the hot issues, because of a great demand for fast response and high density data storage devices, for
More informationV27: RF Spectroscopy
Martin-Luther-Universität Halle-Wittenberg FB Physik Advanced Lab Course V27: RF Spectroscopy ) Electron spin resonance (ESR) Investigate the resonance behaviour of two coupled LC circuits (an active rf
More informationarxiv: v2 [cond-mat.mes-hall] 24 Jan 2011
Coherence of nitrogen-vacancy electronic spin ensembles in diamond arxiv:006.49v [cond-mat.mes-hall] 4 Jan 0 P. L. Stanwix,, L. M. Pham, J. R. Maze, 4, 5 D. Le Sage, T. K. Yeung, P. Cappellaro, 6 P. R.
More informationClassical behavior of magnetic dipole vector. P. J. Grandinetti
Classical behavior of magnetic dipole vector Z μ Y X Z μ Y X Quantum behavior of magnetic dipole vector Random sample of spin 1/2 nuclei measure μ z μ z = + γ h/2 group μ z = γ h/2 group Quantum behavior
More informationLecture #6 Chemical Exchange
Lecture #6 Chemical Exchange Topics Introduction Effects on longitudinal magnetization Effects on transverse magnetization Examples Handouts and Reading assignments Kowalewski, Chapter 13 Levitt, sections
More informationWe have seen that the total magnetic moment or magnetization, M, of a sample of nuclear spins is the sum of the nuclear moments and is given by:
Bloch Equations We have seen that the total magnetic moment or magnetization, M, of a sample of nuclear spins is the sum of the nuclear moments and is given by: M = [] µ i i In terms of the total spin
More informationUses of Nuclear Magnetic Resonance (NMR) in Metal Hydrides and Deuterides. Mark S. Conradi
Uses of Nuclear Magnetic Resonance (NMR) in Metal Hydrides and Deuterides Mark S. Conradi Washington University Department of Physics St. Louis, MO 63130-4899 USA msc@physics.wustl.edu 1 Uses of Nuclear
More informationMore NMR Relaxation. Longitudinal Relaxation. Transverse Relaxation
More NMR Relaxation Longitudinal Relaxation Transverse Relaxation Copyright Peter F. Flynn 2017 Experimental Determination of T1 Gated Inversion Recovery Experiment The gated inversion recovery pulse sequence
More informationThe NMR Inverse Imaging Problem
The NMR Inverse Imaging Problem Nuclear Magnetic Resonance Protons and Neutrons have intrinsic angular momentum Atoms with an odd number of proton and/or odd number of neutrons have a net magnetic moment=>
More informationMuon spin spectroscopy: magnetism, soft matter and the bridge between the two
TOPICAL REVIEW Muon spin spectroscopy: magnetism, soft matter and the bridge between the two L Nuccio 1, L Schulz 2,3, A J Drew 3,4 1 Department of Physics and FriMAT, University of Fribourg, Chemin du
More informationMuonium Transitions in Ge-rich SiGe Alloys
Muonium Transitions in Ge-rich SiGe Alloys Rick Mengyan, M.Sc. Graduate Research Assistant Texas Tech University, Physics Lubbock, TX 79409-1051 USA Collaboration: R.L. Lichti, B.B. Baker, H.N. Bani-Salameh
More informationIntroduction to MRI. Spin & Magnetic Moments. Relaxation (T1, T2) Spin Echoes. 2DFT Imaging. K-space & Spatial Resolution.
Introduction to MRI Spin & Magnetic Moments Relaxation (T1, T2) Spin Echoes 2DFT Imaging Selective excitation, phase & frequency encoding K-space & Spatial Resolution Contrast (T1, T2) Acknowledgement:
More informationLecture #6 NMR in Hilbert Space
Lecture #6 NMR in Hilbert Space Topics Review of spin operators Single spin in a magnetic field: longitudinal and transverse magnetiation Ensemble of spins in a magnetic field RF excitation Handouts and
More informationMuons in Chemistry Training School Dr N J Clayden School of Chemistry University of East Anglia Norwich
Muons in Chemistry Training School 2014 Dr N J Clayden School of Chemistry University of East Anglia Norwich Why use muons? Extrinsic probe (Mu +, Mu, muoniated radical) Intrinsic interest Framing of the
More informationElectron Paramagnetic Resonance
Electron Paramagnetic Resonance Nikki Truss February 8, 2013 Abstract In this experiment a sample of DPPH inside an RF coil, within a Helmholtz coil arrangement, was used to investigate electron paramagnetic
More informationMR Fundamentals. 26 October Mitglied der Helmholtz-Gemeinschaft
MR Fundamentals 26 October 2010 Mitglied der Helmholtz-Gemeinschaft Mitglied der Helmholtz-Gemeinschaft Nuclear Spin Nuclear Spin Nuclear magnetic resonance is observed in atoms with odd number of protons
More informationRelaxation. Ravinder Reddy
Relaxation Ravinder Reddy Relaxation What is nuclear spin relaxation? What causes it? Effect on spectral line width Field dependence Mechanisms Thermal equilibrium ~10-6 spins leads to NMR signal! T1 Spin-lattice
More informationBloch Equations & Relaxation UCLA. Radiology
Bloch Equations & Relaxation MRI Systems II B1 I 1 I ~B 1 (t) I 6 ~M I I 5 I 4 Lecture # Learning Objectives Distinguish spin, precession, and nutation. Appreciate that any B-field acts on the the spin
More informationPhysikalische Chemie IV (Magnetische Resonanz) HS Solution Set 2. Hand out: Hand in:
Solution Set Hand out:.. Hand in:.. Repetition. The magnetization moves adiabatically during the application of an r.f. pulse if it is always aligned along the effective field axis. This behaviour is observed
More informationSupplemental Material to the Manuscript Radio frequency magnetometry using a single electron spin
Supplemental Material to the Manuscript Radio frequency magnetometry using a single electron spin M. Loretz, T. Rosskopf, C. L. Degen Department of Physics, ETH Zurich, Schafmattstrasse 6, 8093 Zurich,
More informationAndrea Morello. Nuclear spin dynamics in quantum regime of a single-molecule. magnet. UBC Physics & Astronomy
Nuclear spin dynamics in quantum regime of a single-molecule magnet Andrea Morello UBC Physics & Astronomy Kamerlingh Onnes Laboratory Leiden University Nuclear spins in SMMs Intrinsic source of decoherence
More informationSpectral Broadening Mechanisms. Broadening mechanisms. Lineshape functions. Spectral lifetime broadening
Spectral Broadening echanisms Lorentzian broadening (Homogeneous) Gaussian broadening (Inhomogeneous, Inertial) Doppler broadening (special case for gas phase) The Fourier Transform NC State University
More informationLow Field MRI of Laser Polarized Noble Gases. Yuan Zheng, 4 th year seminar, Feb, 2013
Low Field MRI of Laser Polarized Noble Gases Yuan Zheng, 4 th year seminar, Feb, 2013 Outline Introduction to conventional MRI Low field MRI of Laser Polarized (LP) noble gases Spin Exchange Optical Pumping
More information5.74 Introductory Quantum Mechanics II
MIT OpenCourseWare http://ocw.mit.edu 5.74 Introductory Quantum Mechanics II Spring 9 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms. Andrei Tokmakoff,
More informationThe Basics of Magnetic Resonance Imaging
The Basics of Magnetic Resonance Imaging Nathalie JUST, PhD nathalie.just@epfl.ch CIBM-AIT, EPFL Course 2013-2014-Chemistry 1 Course 2013-2014-Chemistry 2 MRI: Many different contrasts Proton density T1
More informationSupplemental materials for: Pressure-induced electronic phase separation of magnetism and superconductivity in CrAs
Supplemental materials for: Pressure-induced electronic phase separation of magnetism and superconductivity in CrAs Rustem Khasanov 1,*, Zurab Guguchia 1, Ilya Eremin 2,3, Hubertus Luetkens 1, Alex Amato
More informationNuclear Magnetic Resonance Imaging
Nuclear Magnetic Resonance Imaging Simon Lacoste-Julien Electromagnetic Theory Project 198-562B Department of Physics McGill University April 21 2003 Abstract This paper gives an elementary introduction
More informationMeasuring Spin-Lattice Relaxation Time
WJP, PHY381 (2009) Wabash Journal of Physics v4.0, p.1 Measuring Spin-Lattice Relaxation Time L.W. Lupinski, R. Paudel, and M.J. Madsen Department of Physics, Wabash College, Crawfordsville, IN 47933 (Dated:
More information1 Magnetism, Curie s Law and the Bloch Equations
1 Magnetism, Curie s Law and the Bloch Equations In NMR, the observable which is measured is magnetization and its evolution over time. In order to understand what this means, let us first begin with some
More informationWhat is the susceptibility?
What is the susceptibility? Answer which one? M Initial susceptibility Mean susceptibility M st M 0 0 m High field susceptibility i dm = dh H =0 H st H M M st M 0 0 m i H st H H What is the susceptibility?
More informationMagnetic Resonance in magnetic materials
Ferdinando Borsa, Dipartimento di Fisica, Universita di Pavia Magnetic Resonance in magnetic materials Information on static and dynamic magnetic properties from Nuclear Magnetic Resonance and Relaxation
More informationNuclear spin maser with a novel masing mechanism and its application to the search for an atomic EDM in 129 Xe
Nuclear spin maser with a novel masing mechanism and its application to the search for an atomic EDM in 129 Xe A. Yoshimi RIKEN K. Asahi, S. Emori, M. Tsukui, RIKEN, Tokyo Institute of Technology Nuclear
More informationPhysical fundamentals of magnetic resonance imaging
Physical fundamentals of magnetic resonance imaging Stepan Sereda University of Bonn 1 / 26 Why? Figure 1 : Full body MRI scan (Source: [4]) 2 / 26 Overview Spin angular momentum Rotating frame and interaction
More informationCritical and Glassy Spin Dynamics in Non-Fermi-Liquid Heavy-Fermion Metals
Critical and Glassy Spin Dynamics in Non-Fermi-Liquid Heavy-Fermion Metals D. E. MacLaughlin Department of Physics University of California Riverside, California U.S.A. Leiden p.1 Behavior of spin fluctuations
More informationDisordered Materials: Glass physics
Disordered Materials: Glass physics > 2.7. Introduction, liquids, glasses > 4.7. Scattering off disordered matter: static, elastic and dynamics structure factors > 9.7. Static structures: X-ray scattering,
More informationNuclear spins in semiconductor quantum dots. Alexander Tartakovskii University of Sheffield, UK
Nuclear spins in semiconductor quantum dots Alexander Tartakovskii University of Sheffield, UK Electron and nuclear spin systems in a quantum dot Confined electron and hole in a dot 5 nm Electron/hole
More informationContents of this Document [ntc5]
Contents of this Document [ntc5] 5. Random Variables: Applications Reconstructing probability distributions [nex14] Probability distribution with no mean value [nex95] Variances and covariances [nex20]
More informationSUPPLEMENTARY INFORMATION
doi:10.1038/nature09910 Supplementary Online Material METHODS Single crystals were made at Kyoto University by the electrooxidation of BEDT-TTF in an 1,1,2- tetrachloroethylene solution of KCN, CuCN, and
More informationBiomedical Imaging Magnetic Resonance Imaging
Biomedical Imaging Magnetic Resonance Imaging Charles A. DiMarzio & Eric Kercher EECE 4649 Northeastern University May 2018 Background and History Measurement of Nuclear Spins Widely used in physics/chemistry
More informationChem343 (Fall 2009) NMR Presentation
Chem343 (Fall 2009) NMR Presentation Y Ishii Oct 16, 2009 1 NMR Experiment Cautions Before you start, Read the handouts for background information. Read NMR procedure handouts for the procedures of the
More informationQuantification of Dynamics in the Solid-State
Bernd Reif Quantification of Dynamics in the Solid-State Technische Universität München Helmholtz-Zentrum München Biomolecular Solid-State NMR Winter School Stowe, VT January 0-5, 206 Motivation. Solid
More informationIntroduction to 1D and 2D NMR Spectroscopy (4) Vector Model and Relaxations
Introduction to 1D and 2D NMR Spectroscopy (4) Vector Model and Relaxations Lecturer: Weiguo Hu 7-1428 weiguoh@polysci.umass.edu October 2009 1 Approximate Description 1: Energy level model Magnetic field
More informationNMR Relaxation and Molecular Dynamics
Ecole RMN Cargese Mars 2008 NMR Relaxation and Molecular Dynamics Martin Blackledge IBS Grenoble Carine van Heijenoort ICSN, CNRS Gif-sur-Yvette Solution NMR Timescales for Biomolecular Motion ps ns µs
More informationChem 325 NMR Intro. The Electromagnetic Spectrum. Physical properties, chemical properties, formulas Shedding real light on molecular structure:
Physical properties, chemical properties, formulas Shedding real light on molecular structure: Wavelength Frequency ν Wavelength λ Frequency ν Velocity c = 2.998 10 8 m s -1 The Electromagnetic Spectrum
More informationPrinciples of Magnetic Resonance Imaging
Principles of Magnetic Resonance Imaging Hi Klaus Scheffler, PhD Radiological Physics University of 1 Biomedical Magnetic Resonance: 1 Introduction Magnetic Resonance Imaging Contents: Hi 1 Introduction
More information9 Atomic Coherence in Three-Level Atoms
9 Atomic Coherence in Three-Level Atoms 9.1 Coherent trapping - dark states In multi-level systems coherent superpositions between different states (atomic coherence) may lead to dramatic changes of light
More informationSolution Set 3. Hand out : i d dt. Ψ(t) = Ĥ Ψ(t) + and
Physikalische Chemie IV Magnetische Resonanz HS Solution Set 3 Hand out : 5.. Repetition. The Schrödinger equation describes the time evolution of a closed quantum system: i d dt Ψt Ĥ Ψt Here the state
More informationSketch of the MRI Device
Outline for Today 1. 2. 3. Introduction to MRI Quantum NMR and MRI in 0D Magnetization, m(x,t), in a Voxel Proton T1 Spin Relaxation in a Voxel Proton Density MRI in 1D MRI Case Study, and Caveat Sketch
More informationControl of Spin Systems
Control of Spin Systems The Nuclear Spin Sensor Many Atomic Nuclei have intrinsic angular momentum called spin. The spin gives the nucleus a magnetic moment (like a small bar magnet). Magnetic moments
More informationMagnetic Resonance Imaging. Pål Erik Goa Associate Professor in Medical Imaging Dept. of Physics
Magnetic Resonance Imaging Pål Erik Goa Associate Professor in Medical Imaging Dept. of Physics pal.e.goa@ntnu.no 1 Why MRI? X-ray/CT: Great for bone structures and high spatial resolution Not so great
More informationarxiv:cond-mat/ v2 [cond-mat.mes-hall] 16 Sep 2005
Spin relaxation and decoherence of two-level systems X R Wang Physics Department, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China arxiv:cond-mat/0509395v2 [cond-matmes-hall]
More informationFundamental MRI Principles Module 2 N. Nuclear Magnetic Resonance. X-ray. MRI Hydrogen Protons. Page 1. Electrons
Fundamental MRI Principles Module 2 N S 1 Nuclear Magnetic Resonance There are three main subatomic particles: protons positively charged neutrons no significant charge electrons negatively charged Protons
More informationInvestigating the mechanism of High Temperature Superconductivity by Oxygen Isotope Substitution. Eran Amit. Amit Keren
Investigating the mechanism of High Temperature Superconductivity by Oxygen Isotope Substitution Eran Amit Amit Keren Technion- Israel Institute of Technology Doping Meisner CuO 2 Spin Glass Magnetic Field
More informationSpin Dynamics in One-Dimensional and Quasi One-Dimensional Molecular Magnets
UNIVERSITÀ DEGLI STUDI DI PAVIA DOTTORATO DI RICERCA IN FISICA XX CICLO Spin Dynamics in One-Dimensional and Quasi One-Dimensional Molecular Magnets Manuel Mariani Supervisor: Prof. F. Borsa DOTTORATO
More information3 Chemical exchange and the McConnell Equations
3 Chemical exchange and the McConnell Equations NMR is a technique which is well suited to study dynamic processes, such as the rates of chemical reactions. The time window which can be investigated in
More informationNMR: Formalism & Techniques
NMR: Formalism & Techniques Vesna Mitrović, Brown University Boulder Summer School, 2008 Why NMR? - Local microscopic & bulk probe - Can be performed on relatively small samples (~1 mg +) & no contacts
More informationLinear Differential Equations. Problems
Chapter 1 Linear Differential Equations. Problems 1.1 Introduction 1.1.1 Show that the function ϕ : R R, given by the expression ϕ(t) = 2e 3t for all t R, is a solution of the Initial Value Problem x =
More informationLinear and nonlinear spectroscopy
Linear and nonlinear spectroscopy We ve seen that we can determine molecular frequencies and dephasing rates (for electronic, vibrational, or spin degrees of freedom) from frequency-domain or timedomain
More informationFerdowsi University of Mashhad
Spectroscopy in Inorganic Chemistry Nuclear Magnetic Resonance Spectroscopy spin deuterium 2 helium 3 The neutron has 2 quarks with a -e/3 charge and one quark with a +2e/3 charge resulting in a total
More informationSemiclassical limit and longtime asymptotics of the central spin problem. Gang Chen Doron Bergman Leon Balents
Semiclassical limit and longtime asymptotics of the central spin problem Gang Chen Doron Bergman Leon Balents Trieste, June 2007 Outline The problem electron-nuclear interactions in a quantum dot Experiments
More informationSuperoperators for NMR Quantum Information Processing. Osama Usman June 15, 2012
Superoperators for NMR Quantum Information Processing Osama Usman June 15, 2012 Outline 1 Prerequisites 2 Relaxation and spin Echo 3 Spherical Tensor Operators 4 Superoperators 5 My research work 6 References.
More information13. Basic Nuclear Properties
13. Basic Nuclear Properties Particle and Nuclear Physics Dr. Tina Potter Dr. Tina Potter 13. Basic Nuclear Properties 1 In this section... Motivation for study The strong nuclear force Stable nuclei Binding
More informationMagnetic resonance fingerprinting
Magnetic resonance fingerprinting Bart Tukker July 14, 2017 Bachelor Thesis Mathematics, Physics and Astronomy Supervisors: dr. Rudolf Sprik, dr. Chris Stolk Korteweg-de Vries Instituut voor Wiskunde Faculteit
More information4 Spin-echo, Spin-echo Double Resonance (SEDOR) and Rotational-echo Double Resonance (REDOR) applied on polymer blends
4 Spin-echo, Spin-echo ouble Resonance (SEOR and Rotational-echo ouble Resonance (REOR applied on polymer blends The next logical step after analyzing and concluding upon the results of proton transversal
More informationAtomic Physics (Phys 551) Final Exam Solutions
Atomic Physics (Phys 551) Final Exam Solutions Problem 1. For a Rydberg atom in n = 50, l = 49 state estimate within an order of magnitude the numerical value of a) Decay lifetime A = 1 τ = 4αω3 3c D (1)
More informationSimulations of spectra and spin relaxation
43 Chapter 6 Simulations of spectra and spin relaxation Simulations of two-spin spectra We have simulated the noisy spectra of two-spin systems in order to characterize the sensitivity of the example resonator
More informationSmall Angle Neutron Scattering in Different Fields of Research. Henrich Frielinghaus
Small Angle Neutron Scattering in Different Fields of Research Henrich Frielinghaus Jülich Centre for Neutron Science Forschungszentrum Jülich GmbH Lichtenbergstrasse 1 85747 Garching (München) h.frielinghaus@fz-juelich.de
More informationSpectroscopy in frequency and time domains
5.35 Module 1 Lecture Summary Fall 1 Spectroscopy in frequency and time domains Last time we introduced spectroscopy and spectroscopic measurement. I. Emphasized that both quantum and classical views of
More informationContrast mechanisms in magnetic resonance imaging
Journal of Physics: Conference Series Contrast mechanisms in magnetic resonance imaging To cite this article: M Lepage and J C Gore 2004 J. Phys.: Conf. Ser. 3 78 View the article online for updates and
More informationLaserunterstützte magnetische Resonanz
Laserunterstützte magnetische Resonanz http://e3.physik.uni-dortmund.de Dieter Suter Magnetische Resonanz Prinzip Die MR mißt Übergänge zwischen unterschiedlichen Spin-Zuständen. Diese werden durch ein
More informationLecture2: Quantum Decoherence and Maxwell Angels L. J. Sham, University of California San Diego
Michigan Quantum Summer School Ann Arbor, June 16-27, 2008. Lecture2: Quantum Decoherence and Maxwell Angels L. J. Sham, University of California San Diego 1. Motivation: Quantum superiority in superposition
More informationThe Physical Basis of the NMR Experiment
The Physical Basis of the NMR Experiment 1 Interaction of Materials with Magnetic Fields F F S N S N Paramagnetism Diamagnetism 2 Microscopic View: Single Spins an electron has mass and charge in addition
More informationHelping the Beginners using NMR relaxation. Non-exponential NMR Relaxation: A Simple Computer Experiment.
Helping the Beginners using NMR relaxation. Non-exponential NMR Relaxation: A Simple Computer Experiment. Vladimir I. Bakhmutov Department of Chemistry, Texas A&M University, College Station, TX 77842-3012
More informationSUPPLEMENTARY NOTE 1: ADDITIONAL CHARACTERIZATION OF NANODIAMOND SOLUTIONS AND THE OVERHAUSER EFFECT
1 SUPPLEMENTARY NOTE 1: ADDITIONAL CHARACTERIZATION OF NANODIAMOND SOLUTIONS AND THE OVERHAUSER EFFECT Nanodiamond (ND) solutions were prepared using high power probe sonication and analyzed by dynamic
More informationInfluence of hyperfine interaction on optical orientation in self-assembled InAs/GaAs quantum dots
Influence of hyperfine interaction on optical orientation in self-assembled InAs/GaAs quantum dots O. Krebs, B. Eble (PhD), S. Laurent (PhD), K. Kowalik (PhD) A. Kudelski, A. Lemaître, and P. Voisin Laboratoire
More informationMechanics Physics 151
Mechanics Physics 151 Lecture 11 Rigid Body Motion (Chapter 5) Administravia Please fill out the midterm evaluation form Critical feedback for me to evaluate how well (or badly) I m teaching to adjust
More informationSchematic for resistivity measurement
Module 9 : Experimental probes of Superconductivity Lecture 1 : Experimental probes of Superconductivity - I Among the various experimental methods used to probe the properties of superconductors, there
More informationSpin Feedback System at COSY
Spin Feedback System at COSY 21.7.2016 Nils Hempelmann Outline Electric Dipole Moments Spin Manipulation Feedback System Validation Using Vertical Spin Build-Up Wien Filter Method 21.7.2016 Nils Hempelmann
More informationCHEM / BCMB 4190/6190/8189. Introductory NMR. Lecture 10
CHEM / BCMB 490/690/889 Introductory NMR Lecture 0 - - CHEM 490/690 Spin-Echo The spin-echo pulse sequence: 90 - τ - 80 - τ(echo) Spins echoes are widely used as part of larger pulse sequence to refocus
More information1.b Bloch equations, T 1, T 2
1.b Bloch equations, T 1, T Magnetic resonance eperiments are usually conducted with a large number of spins (at least 1 8, more typically 1 1 to 1 18 spins for electrons and 1 18 or more nuclear spins).
More information