magnetic resonance with single nuclear spin sensitivity
play

Magnetic Resonance with Single Nuclear-Spin Sensitivity Alex - PowerPoint PPT Presentation

1 Magnetic Resonance with Single Nuclear-Spin Sensitivity Alex Sushkov 2 MRI scanner $2 million 7 tons 1500 liters of He 3 4 5 m magnetic force microscopy (MFM) image of hard drive surface topological spin texture in helical magnet Fe


  1. 1 Magnetic Resonance with Single Nuclear-Spin Sensitivity Alex Sushkov

  2. 2 MRI scanner $2 million 7 tons 1500 liters of He

  3. 3

  4. 4 5 ยตm magnetic force microscopy (MFM) image of hard drive surface topological spin texture in helical magnet Fe 0.5 Co 0.5 Si [Nature 465, 901 (2010)]

  5. 5 Magnetic sensors sensitivity resolution MRFM SERF number of detectable Nature 422, 596 (2003) Science 264, 1560 (1994) magnetic moments (spins) SQUID scanning SQUID Phys.Rev.Lett. 12, 159 (1964) Appl.Phys.Lett . 61, 598 (1992)

  6. 6 The challenge: detecting a single proton spin the ultimate limit of magnetization sensitivity ๐ถ ๐‘œ โ‰ˆ ๐œˆ ๐‘œ /๐‘  3 closer is better

  7. 7 Taking magnetic sensing to the nanoscale

  8. 8 Taking magnetic sensing to the nanoscale

  9. 9 Taking magnetic sensing to the nanoscale

  10. 10 Outline 1. The NV color center in diamond: introduction and applications 2. Magnetic sensing with an NV center: the tools 3. NMR experiments with liquid hydrocarbons: detecting 10 4 nuclear spins 4. NMR spectroscopy of single protein molecules: detecting 400 nuclear spins 5. NMR with single nuclear spin sensitivity 6. Outlook

  11. 11 Nitrogen-vacancy (NV) centers in diamond Nitrogen impurity next to a vacancy inside the diamond lattice behaves like a single atom trapped inside the transparent diamond crystal

  12. 12 Making NV centers in diamond โ€œelectronic - gradeโ€ diamond crystal 1. 2. nitrogen ion implantation 3. anneal at 800 C behaves like a single atom trapped inside the transparent diamond crystal

  13. 13 Properties of NV centers in diamond 1. the relevant levels of the NV center are within diamond bandgap, an electric-dipole transition

  14. 14 Properties of NV centers in diamond 1. the relevant levels of the NV center are within diamond bandgap, an electric-dipole transition 2. ground-state electron spin S=1

  15. 15 Properties of NV centers in diamond 1. the relevant levels of the NV center are within diamond bandgap, an electric-dipole transition 2. ground-state electron spin S=1

  16. 16 Properties of NV centers in diamond 1. the relevant levels of the NV center are within diamond bandgap, an electric-dipole transition 2. ground-state electron spin S=1 a two-level system

  17. 17 A schematic sensing experiment with an NV center 1. the relevant levels of the NV center are within diamond bandgap, an electric-dipole transition 2. ground-state electron spin S=1 equal populations at room temperature

  18. 18 A schematic sensing experiment with an NV center 1. the relevant levels of the NV center are within diamond bandgap, an electric-dipole transition 2. ground-state electron spin S=1 3. optical initialization of spin state optical pumping

  19. 19 A schematic sensing experiment with an NV center 1. the relevant levels of the NV center are within diamond bandgap, an electric-dipole transition 2. ground-state electron spin S=1 3. optical initialization of spin state 4. optical readout of spin state less fluorescence more fluorescence

  20. 20 A schematic sensing experiment with an NV center 1. the relevant levels of the NV center are within diamond bandgap, an electric-dipole transition 2. ground-state electron spin S=1 3. optical initialization of spin state 4. optical readout of spin state 5. microwave manipulation of spin state microwave drive

  21. 21 A schematic sensing experiment with an NV center ESR spectroscopy less fluorescence more fluorescence

  22. 22 A schematic sensing experiment with an NV center Rabi oscillations less fluorescence more fluorescence a room-temperature single- spin quantum system

  23. 23 Experimental apparatus RF transmission line on a glass coverslip โ‰ˆ 5 nm ambient conditions 532 nm laser beam oil-immersion microscope objective permanent magnet

  24. 24 Applications of NV centers quantum nuclear spins registers Science 336 , 1283 (2012) quantum metrology โ€ข magnetic fields networks โ€ข nanophotonics โ€ข electric fields โ€ข mechanical โ€ข temperature resonators โ€ข gyroscopes Nature 466 , 730 (2010) Nature Physics 4 , 810 (2008) Nature 497 , 86 (2013) Science 339 , 561 (2013) Science 335 , 1603 (2012) Nature Physics 7 , 459 (2011) Nature 500 , 54 (2013) Phys. Rev. A 86 , 0521226 (2012) Physics Today 67 , 38 (2014) Scientific American 297 , 84 (2007)

  25. 25 Outline 1. The NV color center in diamond: introduction and applications 2. Magnetic sensing with an NV center: the tools

  26. 26 NV-based magnetic sensing schemes population and coherence of ground-state sublevels โ€ข fast-oscillating fields (>GHz) ๏ƒ  NV population transfer (incoherent) all-optical magnetic detection of single-atom Gd spins at room temperature Alex Sushkov, Nick Chisholm, Igor Lovchinsky, et al., Nano Lett . 14 , 6443 (2014) probing magnetic Johnson noise at the nanometer scale, electron ballistic transport Shimon Kolkowitz, Arthur Safira, et al., Science, in press

  27. 27 NV-based magnetic sensing schemes population and coherence of ground-state sublevels โ€ข fast-oscillating fields (>GHz) ๏ƒ  NV population transfer (incoherent) โ€ข radiofrequency fields (kHz โ€“ 100 MHz) ๏ƒ  NV echo magnetometry (coherent) B n B 0 Larmor precession of a nuclear spin: time

  28. 28 NV spin echo magnetic sensing static or slowly-varying magnetic field ๏ƒ  optical ๐œ’ 1 โˆ ๐ถ ๐‘œ ๐œ ๐œ’ 2 โˆ โˆ’๐ถ ๐‘œ ๐œ fluorescence pumping spin readout into m s =0 ๐œ’ 1 + ๐œ’ 2 = 0

  29. 29 NV spin echo magnetic sensing oscillating magnetic field ๏ƒ  optical ๐œ’ 1 โˆ ๐ถ ๐‘œ ๐œ ๐œ’ 2 โˆ โˆ’(โˆ’๐ถ ๐‘œ )๐œ fluorescence pumping spin readout into m s =0 ๐œ’ 1 + ๐œ’ 2 โˆ 2๐ถ ๐‘œ ๐œ spin echo sensitive to magnetic fields at frequencies ~๐Ÿ/๐Ÿ‘๐Š

  30. 30 NV CPMG (Carr-Purcell-Meiboom-Gill) magnetic sensing NV center spin ๏ƒ  magnetic spectrometer optical fluorescence pumping spin readout into m s =0 โ€ข robust against pulse errors โ€ข longer NV T 2 due to dynamical decoupling from environment spectral selectivity by varying free evolution interval ๏ด โ€ข

  31. 31 Outline 1. The NV color center in diamond: introduction and applications 2. Magnetic sensing with an NV center: the tools 3. NMR experiments with liquid hydrocarbons: detecting 10 4 nuclear spins

  32. 32 An NV-based NMR experiment target sample with nuclear spins randomly-oriented proton spins add to give zero net magnetic field: ๐ถ ๐‘œ = 0 but there is a โ€œstatistical polarizationโ€ ~ ๐‘‚ 2 โ‰  0 ๐ถ ๐‘œ 2 measure variance of nuclear magnetic field: ๐ถ ๐‘œ

  33. 33 First NMR experiments: protons in immersion oil NV magnetometry measures magnetic field B n from proton spins in objective oil proton spins depth XY-32 depth = (8.2 ยฑ 0.1) nm detecting โ‰ˆ 10 4 nuclear spins NV depth extracted from proton peak magnitude S. DeVience, L.Pham, I. Lovchinsky, et al., H. Mamin, et al., Science 339 , 557 (2013) Nature Nano , DOI: 10.1038 (2015) T. Staudacher et al., Science 339 , 561 (2013)

  34. 34 Outline 1. The NV color center in diamond: introduction and applications 2. Magnetic sensing with an NV center: the tools 3. NMR experiments with liquid hydrocarbons: detecting 10 4 nuclear spins 4. NMR spectroscopy of single protein molecules: detecting 400 nuclear spins

  35. 35 Experimental sensitivity parameters optical ๐œ’ 2 โˆ โˆ’(โˆ’๐ถ ๐‘œ )๐œ ๐œ’ 1 โˆ ๐ถ ๐‘œ ๐œ fluorescence pumping spin readout into m s =0 ๐œ’ 1 + ๐œ’ 2 โˆ 2๐ถ ๐‘œ ๐œ 2 โ‰ˆ ๐œˆ ๐‘œ 2 /๐‘  6 ๐ถ ๐‘œ signal: closer is better 2๐œ โ‰ˆ ๐‘ˆ 2 NV spin coherence time: longer ๐‘ˆ 2 is better NV spin readout fidelity higher fidelity is better

  36. 36 Coherence times of shallow NV centers O H shallow NV centers display likely due to surface electron C faster decoherence spins (dangling bonds) anneal diamond at 465 C in oxygen atmosphere 10-fold improvement in T 2 Igor Lovchinsky, Alex Sushkov, Elana Urbach, Nathalie de Leon, et al. manuscript in preparation

  37. 37 NV spin readout optical fluorescence pumping spin readout ๏‚ฎ | 0 measurement result is stored optical readout destroys NV electron spin state ๏‚ฎ | 0 in the NV electron spin state: ฮฑ| 0 + ๐›พ| โˆ’1 how well did we measure ฮฑ, ๐›พ ? poor fluorescence < 1% fidelity collection efficiency

  38. 38 Improving NV spin readout using quantum logic electron J=1 15 N nuclear I=1/2 ๏ƒ„ hyperfine: ๐ผ = ๐ต๐‘ฒ โˆ™ ๐‘ฑ electron spin | โˆ’1 ๐ต โ‰ˆ 3 MHz CNOT gate: flip electron spin 2.87 GHz conditional on nuclear spin state | 0 SWAP electron spin state | | โ†“ โ†‘ with nuclear spin state: nuclear spin ฮฑ 0 + ๐›พ โˆ’1 โ†’ ๐›ฝ| โ†“ + ๐›พ| โ†‘ nuclear spin state is NOT repetitive readout D. Hume, et al., destroyed by optical excitation Phys. Rev. Lett . 99 , 120502 (2007)

  39. 39 Improving NV spin readout using quantum logic | 0 | ๐‘“ | ๐‘œ SWAP repetitive readout | e โ†” | n of 15 N nuclear spin improved NV spin readout efficiency by ร— 30 Igor Lovchinsky, Alex Sushkov, Elana Urbach, Nathalie de Leon, et al. manuscript in preparation

  40. 40 Single ubiquitin proteins ubiquitin protein, enriched with 13 C (I=1/2) and 2 H (I=1) covalent attachment of ubiquitin protein to diamond surface: AFM of a clean diamond surface: AFM of a diamond surface with attached proteins:

Recommend


More recommend