Preparation of reduced-quantum-uncertainty input states for an atomic clock
Atomic clocks have reached the Standard Quantum Limit (SQL) of precision,1 set by the projection noise inherent in measurements on uncorrelated atoms. It is possible to overcome this limit by entangling the atoms to generate a "squeezed state" of the atomic ensemble. We use the collective...
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| Format: | Article |
| Language: | en_US |
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Society of Photo-optical Instrumentation Engineers
2010
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| Online Access: | http://hdl.handle.net/1721.1/52734 https://orcid.org/0000-0002-9786-0538 |
| _version_ | 1826214233907396608 |
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| author | Schleier-Smith, Monika Helene Leroux, Ian Daniel Vuletic, Vladan |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Schleier-Smith, Monika Helene Leroux, Ian Daniel Vuletic, Vladan |
| author_sort | Schleier-Smith, Monika Helene |
| collection | MIT |
| description | Atomic clocks have reached the Standard Quantum Limit (SQL) of precision,1 set by the projection noise inherent in measurements on uncorrelated atoms. It is possible to overcome this limit by entangling the atoms to generate a "squeezed state" of the atomic ensemble. We use the collective interaction of an atomic ensemble with a far-detuned light field in an optical resonator to prepare squeezed states by two different methods: quantum non-demolition (QND) measurement and Hamiltonian evolution. We apply both methods to an ensemble of 5 x 10[superscript 4] [superscript 87]Rb atoms in a superposition of hyperfine clock states. We measure the suppression of projection noise and compare it to the accompanying reduction in signal, thereby quantifying the net gain in spectroscopic sensitivity. By QND measurement, with resolution up to 9 dB below the projection noise level, we achieve 3.0(8) dB of metrologically relevant squeezing. Whereas the measurement-based approach relies on knowledge of the (randomly distributed) measurement outcome to produce a conditionally squeezed state, the method of Hamiltonian evolution produces a known squeezed state independent of detector performance. We mimic the dynamics of the one-axis twisting Hamiltonian, proposed as a generator of squeezed states by Kitagawa and Ueda, by using the atom-induced frequency shift of the resonator mode and the corresponding resonator-field-induced shift of the atomic transition frequency to introduce an effective interaction among the atoms. The resulting deterministic squeezing is sufficient to allow a 6.0(4) dB improvement in spectroscopic sensitivity over the SQL |
| first_indexed | 2024-09-23T16:02:14Z |
| format | Article |
| id | mit-1721.1/52734 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T16:02:14Z |
| publishDate | 2010 |
| publisher | Society of Photo-optical Instrumentation Engineers |
| record_format | dspace |
| spelling | mit-1721.1/527342022-10-02T05:51:35Z Preparation of reduced-quantum-uncertainty input states for an atomic clock Schleier-Smith, Monika Helene Leroux, Ian Daniel Vuletic, Vladan Massachusetts Institute of Technology. Department of Physics Massachusetts Institute of Technology. Research Laboratory of Electronics Vuletic, Vladan Schleier-Smith, Monika Helene Leroux, Ian Daniel Vuletic, Vladan Atomic clocks have reached the Standard Quantum Limit (SQL) of precision,1 set by the projection noise inherent in measurements on uncorrelated atoms. It is possible to overcome this limit by entangling the atoms to generate a "squeezed state" of the atomic ensemble. We use the collective interaction of an atomic ensemble with a far-detuned light field in an optical resonator to prepare squeezed states by two different methods: quantum non-demolition (QND) measurement and Hamiltonian evolution. We apply both methods to an ensemble of 5 x 10[superscript 4] [superscript 87]Rb atoms in a superposition of hyperfine clock states. We measure the suppression of projection noise and compare it to the accompanying reduction in signal, thereby quantifying the net gain in spectroscopic sensitivity. By QND measurement, with resolution up to 9 dB below the projection noise level, we achieve 3.0(8) dB of metrologically relevant squeezing. Whereas the measurement-based approach relies on knowledge of the (randomly distributed) measurement outcome to produce a conditionally squeezed state, the method of Hamiltonian evolution produces a known squeezed state independent of detector performance. We mimic the dynamics of the one-axis twisting Hamiltonian, proposed as a generator of squeezed states by Kitagawa and Ueda, by using the atom-induced frequency shift of the resonator mode and the corresponding resonator-field-induced shift of the atomic transition frequency to introduce an effective interaction among the atoms. The resulting deterministic squeezing is sufficient to allow a 6.0(4) dB improvement in spectroscopic sensitivity over the SQL National Science Foundation, Center for Ultracold Atoms Defense Advanced Research Projects Agency National Science Foundation 2010-03-18T20:26:22Z 2010-03-18T20:26:22Z 2009-08 2009-08 Article http://purl.org/eprint/type/JournalArticle 0277-786X SPIE CID: 743107-10 http://hdl.handle.net/1721.1/52734 Schleier-Smith, M. H., I. D. Leroux, and V. Vuletic. “Preparation of reduced-quantum-uncertainty input states for an atomic clock.” Time and Frequency Metrology II. Ed. Tetsuya Ido & Derryck T. Reid. San Diego, CA, USA: SPIE, 2009. 743107-10. © 2009 SPIE https://orcid.org/0000-0002-9786-0538 en_US http://dx.doi.org/10.1117/12.828171 Proceedings of SPIE--the International Society for Optical Engineering Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf Society of Photo-optical Instrumentation Engineers SPIE |
| spellingShingle | Schleier-Smith, Monika Helene Leroux, Ian Daniel Vuletic, Vladan Preparation of reduced-quantum-uncertainty input states for an atomic clock |
| title | Preparation of reduced-quantum-uncertainty input states for an atomic clock |
| title_full | Preparation of reduced-quantum-uncertainty input states for an atomic clock |
| title_fullStr | Preparation of reduced-quantum-uncertainty input states for an atomic clock |
| title_full_unstemmed | Preparation of reduced-quantum-uncertainty input states for an atomic clock |
| title_short | Preparation of reduced-quantum-uncertainty input states for an atomic clock |
| title_sort | preparation of reduced quantum uncertainty input states for an atomic clock |
| url | http://hdl.handle.net/1721.1/52734 https://orcid.org/0000-0002-9786-0538 |
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