A quantum bouncing ball gravity spectrometer

Transcription

1 qbounce A quantum bouncing ball gravity spectrometer Hartmut Abele Schloss Waldthausen 13. April 2016 Hartmut Abele, TU Wien

2 how Case I: free fall at short distances Julio Gea-Banacloche, Am. J. Phys.1999 Quantum interference: sensitivity to fifth forces Simulation: Reiter, Schlederer, Seppi Hartmut Abele, Atominstitut, TU Wien Rafael Reiter, Bernhard Schlederer, David Sepp

3 BOUNCE: Quantum States in the Gravity Potential Schrödinger Equation Bound States 1/ z 0 = + mgz ϕ ( ) = 5.87 ( ) 2 n z = Enϕn z µ m 2m z mm i g g 1/ mg g E0 = = 0.602peV 2m i Discrete energy levels Ground state 1.4 pev Airy-Functions ψ 2

4 Frequency: Resonance Spectroscopy Quantum System, 2-Level System Coupling Example: - NMR: - Magnetic Moment in - outer magnetic field - RF-field drives Transitions - Rabi Spectroscopy - Ramsey Spectroscopy: Clocks, Spin Echo, EDM All Spectroscopy methods so far use electromag fields or a coupling to a electromag. potential

5 Gravity Resonance Spectroscopy Quantum System, 2-Level System Coupling GRS: Neutron - gravity field of earth, 3 > 3.32 pev - oscillating Mirror drives transitions 1 > 1.4 pev qbounce: Vibrating mirror Demonstration Gravity Resonance Spectroscopy:Jenke et al., Nature Physics 2011

6 Rabi Spectroscopy 1938 NMResonance-Spectroscopy -Technique For measurements of magnetic moments No signal Detector Mag. Radio frequency Summary Energy measurement is related to frequency measurements Signal in Detector 7

7 Show Case II: Rabi-type Spectroscopy of Gravity NMR Spectroscopy Technique to explore magnetic moments 3 Regions: I: 1st State selector/ Polarizer II: Coupling RF field III: 2nd State Selector / Analyzer Gravity Resonance Spectroscopy Technique to explore gravity 3 Regions: I: 1st State selector/ Polarizer II: Coupling Vibr. mirror III: 2nd State Selector / Analyzer

8 Region I

9 Airy - Quantum States 1 & 2 7 Li * n+ 10 B + α CR39-Plastik mit Neutronenkonverter (200nm ) UCN rough mirror neutron mirror Jenke et al. NIM 2013, PRL µm ~ 10 cm 11

10 V. Nesvizhevsky et al., Eur. Phys. Lett. (2005) A. Westphal et al., Eur. Phys. Lett. (2007) 2002: Observation of Bound Quantum States Neutron mirror: polished glass plate 10 cm long V. Nevizhevsky et al., Nature (2002).

11 Observation of the Spatial Distribution of Gravitationally Bound Quantum States G. Ichikawa et al., Phys. Rev. Lett. 112, (2014) 13

12 O. Zimmer arxiv: [nucl-ex] O. Zimmer: Neutrons on a surface of liquid helium Scattering rate - Bulk phonons - Ripplons - Surfons - vapour

13 Region II

14 Region 2: the vibration table

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17 Region III

18 Detector

19 qbounce Gravity Resonance Spectroscopy 1> 3> : 462 Hz 1> 4> : 647 Hz T. Jenke et al. NP > 2> : 266 Hz 1> 3> : 563 Hz 2> 3> : 296 Hz 2> 4> : 701 Hz T. Jenke et al. PRL > 3> : 462 Hz 1> 4> : 647 Hz C. Cronenberg et al.

20 Results Transitions 1-3 and 1-4 observed 1-3: (46±5)% Intensity drop 1-4: (61±7)% mm/s Preliminary, Thesis Cronenberg

21 Rabi Oscillation 462Hz 647Hz State Revival Ω τ = π R L Q13A = µ S Thesis Cronenberg 20cm 7.4m/s m 2.2mm/s = π

22 DFG/FWF Priority Programme 1491 : Precision experiments in particle- and astrophysics with cold and ultracold neutrons, Participating Institutions: IST Braunschweig Univ. Heidelberg ILL Univ. Jena Univ. Mainz Exzellenzcluster Universe München Techn. Univ. München * PTB Berlin Vienna University of Technology * Priority Areas CP-symmetry violation and particle physics in the early universe. The structure and nature of weak interaction and possible extensions of the Standard Model. Tests of gravitation with quantum objects Charge quantization and the electric neutrality of the neutron. New Infrastructure (UCN-Source, cold Neutrons) - * Coordinators first round (S. Paul, H.A. )

23 Priority Programme 1491 Research Area A: CP-symmetry violation and particle physics in the early universe - Neutron EDM E = ev Research Area B: The structure and nature of weak interaction and possible extensions of the Standard Model - Neutron β-decay V A Theory Research Area C: Test of gravitation with quantum interference - Neutron bound gravitational quantum states Research Area D: Charge quantization and the electric neutrality of the neutron - Neutron charge Research Area E: New measuring techniques - Particle detection - Magnetometry - Neutron optics

24 Priority area A: CP-symmetry violation and particle physics in the early universe. The focus is a next generation experiment to measure the neutron electric dipole moment with a sensitivity increased by at least one order of magnitude within the next six years Experiment at a new ucn source New setup (nedm) New µ-metal shield (multi-layers) B-Field Stability (10 ft) / Uniformity (3pT/cm) Sensitivity: d n = 0 : d n < 1-2 x e cm (95% C.L.) Ramsey-Method of separated oscillating fields π /2 π /2?

25 Charge quantization and the electric neutrality of the neutron. Since the Standard Model value for q n requires extreme fine tuning, the smallness of this value may be considered as a hint for GUTs, where q n is equal to zero. Improve limit by two orders of magnitude

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28 Gravity at short distances: String theories Illustration: Savas Dimopoulos Adelberger: In oder to see the true strength of gravitation, you have to be very close.

29 Neutrons test Newton m m Vr G e r 1 2 λ = + α r/ ( ) (1 ) Strength α Range λ For a neutron with mass m n, gravitational constant G, mass m E and density ρ of the earth with radius R E (r = R E + z), V(r) is usually approximated by V ( z) = mn gz V z m Ge 2 2 z / λ 12 (, λ) = 2π nραλ = α 2 10 pev 31

30 Neutrons test Newton m m Vr = G + α e r 1 2 / ( ) (1 r λ ) Strength α Range λ Hypothetical Gravity Like Forces Extra Dimensions: The string and D p -brane theories predict the existence of extra space-time dimensions Infinite-Volume Extra Dimensions: Randall and Sundrum Exchange Forces from new Bosons: a deviation from the ISL can be induced by the exchange of new (pseudo)scalar and (pseudo)vector bosons Axion µm < λ < 0.2 cm Scalar boson. Cosmological consideration Bosons from Hidden Supersymmetric Sectors Gauge fields in the bulk (ADD, PRD 1999) < α < 10 9 Supersymmetric large Extra Dimensions (B.& C.) α <

31 the Rainbow: Newton Light beam that hits a rain drop is refracted toward the middle of the drop and then repeatedly reflected into the drop Newton s Explanation(Photons) - white light was composed of the light of all the colours of the rainbow, which a glass prism could separate into the full spectrum of colours, rejecting the theory that the colours were produced by a modification of white light.

32 The Rainbow: Descartes DE L'ARC-EN-CIEL Light beam that hits a rain drop is refracted toward the middle of the drop and then repeatedly reflected into the drop again upon enclicht wird am Regentropfen gebrochen und reflektiert (1637).

33 The rainbow again

34 George Biddell Airy The Airy Funktion:

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36 M. Thalhammer, T. Jenke et al. Snapshots with spatial resolution detectors ~ 1.5 µm ie t/ n Ψ (,) zt = ce ψ () z n = 0 n z En ψ ()~ z Ai[ ]; c = Ψ(,0) z ψ() z dz n n z E 0 0 n 0 Courtesy: M. Thalhammer L

37 Preparation L = 0 Courtesy: M. Thalhammer

38 2nd bounce, 2nd turning point, L = 41 mm Courtesy: M. Thalhammer

39 Move downwards, L = 51 mm Courtesy: M. Thalhammer

40 L = 54 mm 42

41 L = µm

42 The Team at Atominstitut Gravity tests with quantum objects - G. Cronenberg, H. Filter, P. Geltenbort (ILL), T. Jenke, H. Lemmel, M. Thalhammer, T. Rechberger, J. Herzinger, U. Schmidt (HD), T. Lauer (TUM), Collaboration HD, TUM, ILL Neutron Beta Decay, PERC collaboration - J. Erhart, E. Jericha, D. Moser, P. Haydn, G. Konrad, M. Klopp, H. Saul, X. Wang, Collaboration with HD, MZ, TUM, ILL Interferometry - G. Badurek, H. Rauch, Y. Hasegawa, M. Zawisky, J. Summhammer, D. Erdösi, G. Sulyok, S. Sponar, H. Geppert Neutron Radiography - M. Zawisky N_TOF/USANS: E. Jericha, C. Weiß, H. Rauch, G. Badurek,H. Leeb, Griesmayer