Precision sensing using quantum defects

Transcription

1 Precision sensing using quantum defects Sang-Yun Lee 3rd Institute of Physics, University of Stuttgart, Germany Quantum and Nano Control, IMA at University of Minnesota April 14, 2016

2 Single spin probes towards optical magnetic imaging in nanoscale Sang-Yun Lee 3rd Institute of Physics, University of Stuttgart, Germany Quantum and Nano Control, IMA at University of Minnesota April 14, 2016

3 Eg=5.5 ev 1.945eV Defect based quantum systems as a probe Color centers in solids: Nitrogen-vacancy center (NV center) in diamond CB ES VB GS Optically detected spin signal Point defect Carbon vacancy + Nitrogen impurity 500nm By confocal fluorescence microscopy

4 Optical detection of a NV center spin New J. Phys. 13, (2011)

5 Optical detection of a NV center spin m S = 1 m S = 0 m S = 1 S=1 ms = 0 ESR@2.87 GHz At zero magnetic field (B 0 =0) Annu. Rev. Condens. Matter Phys. 4, 23 (2013)

6 Optical detection of a NV center spin Optical single electron spin detection at room temperature Optically Detected Magnetic Resonance 0 = bright 1 = dark A. Gruber, et al., Science 276, 2012 (1997).

7 Photon-Spin Quantum Systems Diamond Ladd et al. Nature 2010 Cer,Pr/YAG Kolesov et al. Nature Comm SiC Widmann et al. Nature Materials 2015 Christle et al. Nature Materials2015

8 Color centers in solids magnetic field sensitivity C 1 ηt C: ODMR contrast : # of photons per measurement T: measurement time ( T 2 ) Single spin detection diamond SiC NV - V Si Divacancy Y Y Y T µs (RT, LT) 100 µs (RT)* 100 µs (RT) 1 ms (LT) PL intensity 100 kcps 10 kcps 10 kcps ODMR contrast 30 % Relative sensitivity 1 4 % (RT) 160 % (LT)** 0.02 (RT) 3 (LT) 0.1 % (RT) 40 % (LT) (RT) 0.8 (LT) * M. Widmann, S.-Y. Lee*, et al., Nat Mater 14, 164 (2015). **Our recent result, unpublished. Christle, et al., Nature Materials 14, 160 (2015). Falk, et al. Phys. Rev. Lett. 112, (2014).

9 Color centers in solids Single spin detection magnetic field sensitivity C diamond 1 ηtn SiC NV - V Si Divacancy Y Y Y T µs (RT, LT) 100 µs (RT)* C: ODMR contrast : # of photons per measurement T: measurement time ( T 2 ) N: # of spins 100 µs (RT) 1 ms (LT) PL intensity 100 kcps 10 kcps 10 kcps ODMR contrast 30 % Relative sensitivity 1 4 % (RT) 160 % (LT)** 0.02 (RT) 3 (LT) 0.1 % (RT) 40 % (LT) (RT) 0.8 (LT) * M. Widmann, S.-Y. Lee*, et al., Nat Mater 14, 164 (2015). **Our recent result, unpublished. Christle, et al., Nature Materials 14, 160 (2015). Falk, et al. Phys. Rev. Lett. 112, (2014).

10 What to do with spin color centers? Motivation: Quantum computer Solid state spin qubits Quantum computer in future, maybe. NV center in diamond

11 Solid state qubits Quantum computation Quantum communication Indistinguishable single photon source Sold state qubit Quantum gate, e.g. CNOT Phys. Rev. Lett. 113, (2014) Science 329, 542 (2010) Long coherence time Spin-photon interface Quantum register Quantum error correction Science 336, 1283 (2012) Nature 497, (2013) arxiv (2015) Nature 506, 204 (2014)

12 Hybrid qubits: electron spin + nuclear spin spins Magnetic moment manipulation Single spin detection Coherence time (T 2 ) Electron Strong Fast Easy Short ( 100 µs) Role Control/ Detection Nucleus Weak Slow Hard Long ( 1 s) memory Hybrid solid state qubit 13 C 1% 14 N 99.6%

13 Solid state qubits Quantum computation Quantum communication Indistinguishable single photon source Sold state qubit Quantum gate, e.g. CNOT Phys. Rev. Lett. 113, (2014) Science 329, 542 (2010) Long coherence time Spin-photon interface Quantum register Quantum error correction Science 336, 1283 (2012) Nature 497, (2013) arxiv (2015) Nature 506, 204 (2014)

14 Quantum metrology Optical (magnetic) imaging applications! Single photon source Optical imaging Long coherence time Sensitivity (coherence time) -1/2 Quantum gate Sensing protocol Hybrid qubits: electron+nuclear spin Sensor+memory pair Industry friendly platform: SiC Practical device

15 Quantum metrology In Coupling to external AC & DC magnetic field Ĥ S D S S g B Magnetic field sensing in nano scale Spin dipolar interaction: E-field, temperature & pressure dependent Electric field sensing Strain and pressure sensing Thermometry

16 DC vector magnetometry For S=1, e.g. NV center in diamond Ĥ S D S S g B Provided by Torsten Rendler

17 Optical single spin detection setup Home-built Confocal fluorescence microscope + MW and RF radiation + magnet

18 Optical magnetic imaging Best spatial resolution=0.8 nm S. Steinert, Nat Commun (2013) M.S. Grinolds et al., Nat Nano 9 29 (2014)

19 Optical magnetic imaging NV center1 NV center2 Living Hela cell fluorescent nanodiamond particles Bright Stable Biocompatible 1 nm* Intensity (arb. u) nm CVD diam. Imp. IIa diam. powder Optical magnetic imaging of a magnetotactic bacteria (MTB) nanodiam. 2 D. Le 720Sage, 730 et 740 al., 750Nature (2013) occurency (#) nm (a) nm nanodiam. (c) wavelength (nm) intensity (arb. u.) nm (d) peak position (nm) y ( m) nanodiam wavelength (nm) k 48k 32k 16k x ( m) *I. I. Vlasov, et al., Nat Nano 9, 54 (2014). (b) Tracking position and rotation in 100 ms scale L. P. McGuinness, et al., Nat Nano (2011)

20 Optical magnetic imaging Characterization of HDD head axiv: (2016)

21 DC vector magnetometry DC magnetometry Useful for optical magnetic imaging Frequency (magnetic field) sweep Slow! Time domain measurement Fast High sensitivity AC sensing

22 Optical AC magnetometer in time domain FID based sensing /2 φ 0 τ B 0 dt i 0 e 1 2 2

23 Optical AC magnetometer in time domain Ramsey interferometer sensitivity 1 T 2 Optical polarization Laser π 2 φ T 2* 1 µs 0 τ B 0 dt π 2 Read Laser i 0 e 1 2 AC magnetic field D e.g. Nuclear spin Larmor precession = n B 0 B 0

24 Optical AC magnetometer in time domain Optical polarization φ Laser Dynamic decoupling Noise filter Quantum lock-in detection π 2 sensitivity 1 T µs π π π C T 2 = n /2 π 2 Read Laser AC magnetic field e.g. Nuclear spin Larmor precession = n B 0 B 0 D

25 Optical AC magnetometer in time domain Science 339, 561 (2013).

26 Nano NMR Science 339, 561 (2013). Few nuclear spins: Müller et al. Nature Comm Degen et al. PRL 2014

27 Nano NMR Single Protein Detection F. Shi, JW et al. Science 2015

28 Towards practical NMR in nanoscale Single electron spin sensor NMR in nanoscale: resolution 10 khz by T 2,e 'Classical' NMR sensors: Molecular structure analysis (chemical shift, 2D-NMR) CH 3 C=O OH CH 2 CH 3 chemical shift gives 'building blocks' Becker, Edwin D., High Resolution NMR, Academic Press, Wu et al. PLoS Pathogens 6 (6): e D-NMR gives 'molecular structure' Required resolution: <100 Hz! ppm 127 Hz) By Matthias Pfender

29 Optical AC magnetometer in time domain Quantum correlation measurement to overcome limit by T 2e <T 2e T c sensing sensing φ 0 τ B 0 dt Correlation Memory is saved We need a memory to store 1 for T c!! Nuclear spin T 2,n >1ms By entanglement D AC magnetic field B 0 = n B 0

30 Entanglement? Read Know! Quantum communication, quantum key distribution, quantum gate.

31 Entanglement for sensing NV center electron spin: sensor T 2e 400 µs 14 N nuclear spin: quantum memory T 2n 5 ms Rotating nuclear spin 0 e 0 n 1 e 1 n Single electron spin only preparation 0 1 e e φ 0 τ B 0 dt Entangled sensor and memory pair 0 e 0 n + 1 e 1 n preparation sensing i 0 e 1 e e 0 e 0 n +e -i 1 e 1 n Sensing & storage 1 e ( 0 n +e -i 1 n ) disentanglement for memory protection

32 Entanglement for sensing 1 e 1 n 1 e 0 n 1 0 e 1 n 5 π e 3 π e e ( 0 n + 1 n )= 0 e 0 n + 0 e 1 n 0 e 0 n + 1 e 1 n entangled!! 0 e 0 n 0 e 1 n 4 Wait for : 0 e 0 n +e -i 1 1 e 1 n 5 1 e 0 n +e -i 1 1 e 1 n = 1 e ( 0 n +e -i 1 1 n ) 2 π 2 n e ( 0 n +e -i( 1-2) 1 n ) π 2 n π e π e T c 6 π e D 8 7 π e B 0 t

33 Entanglement for sensing Quantum circuit diagram: full sensing protocol sensing φ 1 stored (φ 1 ) in a nuclear spin (memory) sensing φ 1 -φ 2 readout entangle ment disentang lement entangle ment disentangl ement τ/2 T c 13 C bath D B 0

34 Single 13 C NMR by spin sensor 13 C nuclear spins B 0 =540 mt S. Zaiser et al., submitted

35 Single 13 C NMR by spin sensor Continuous polarization, 3 khz 13 C pump 13 C bath FID 6 µw orange: T 2 *=17 ms linewidth: 58 Hz! Matthias Pfender, Nabeel Aslam et al., in preparation

36 FFT of previous FID signal. Lorentzian fit reveals linewidth of 15 Hz FWHM=15.2 Hz B 0 =1.5T

37 Towards nano NMR & MRI 2D NMR Molecular dynamics Optical imaging Nat Commun 6, (2015). Enhanced resolution: Currently, 10 Hz Goal 1 Hz NMR, 2D NMR, magnetic imaging in nanoscale for biology & medicine for single molecule spectroscopy

38 Towards nano NMR & MRI

39 Nano NMR Sebastian Zaiser, Matthias Pfender, Nabeel Aslam, Torsten Rendler, Ingmar Jakobi, Thomas Wolf, Philip Neumann, Jörg Wrachtrup In collaboration with: M. D. Lukin (Harvard), R. Walsworth J. Meyer (Leipzig) S. Prawer, L. Hollenberg (University of Melbourne) P. R. Hemmer (Texas A&M) N. B. Manson (Australian National University) F. Schmidt-Kaler, K. Singer (Mainz) V. Jacques, JF. Roch ENS Cachan G. Balasubramanian (MPI Göttingen) F. Jelezko et al. (Ulm) Renbao Liu (CUHK), N. Miziochi (Osaka University)