<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>N</mml:mi><mml:mo>−</mml:mo><mml:mi>atom</mml:mi></mml:mrow></mml:math>collective-state atomic clock with<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msqrt><mml:mi>N</mml:mi></mml:msqrt><mml:mo>−</mml:mo><mml:mi>fold</mml:mi></mml:mrow></mml:math>increase in effective frequency and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msqrt><mml:mi>N</mml:mi></mml:msqrt><mml:mo>−</mml:mo><

Kim, May E.; Sarkar, Resham; Fang, Renpeng; Shahriar, Selim M.

doi:10.1103/physreva.91.063629

Cited by 7 publications

(6 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the system acts as a single particle, which reduces the effective SNR by the factor of √ N . As a result, we have shown that the QFF for the COSAC is essentially the same as that for the CAC [17].…”

Section: A Conventional Atomic Clock and Collective State Atomic Clockmentioning

confidence: 68%

“…In order to describe how the CSD-SCAC and the CD-SCAC work, it's useful to review briefly some details about the conventional atomic clock (CAC) as well as the collective state atomic clock (COSAC) [17]. Here we consider a system where the ground states, |1 and |2 of a three-level atom interact with an excited state |3 via two copropagating laser beams.…”

Section: A Conventional Atomic Clock and Collective State Atomic Clockmentioning

confidence: 99%

“…The COSAC can thus be viewed as the aggregation of interference patterns due N +1 2 CAC's working simultaneously [17]. The narrowest constituent signal fringes are derived from interferences between states with the largest difference in phase, i.e.…”

Section: A Conventional Atomic Clock and Collective State Atomic Clockmentioning

confidence: 99%

“…In ref. [13] we proposed a Schrödinger Cat atomic interferometer (SCAIN) that makes use of critically tuned OATS, rotation, inverse rotation and unsqueezing, which, in combination with collective state detection (CSD) [14][15][16][17][18], reduces the SDS by a factor of √ N , while leaving the PGS unchanged, yielding Λ = N . In what follows, we will refer to this as the CSD-SCAIN.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Increasing Sensitivity of an Atom Interferometer to the Heisenberg Limit using Enhanced Quantum Noise

Fang¹,

Sarkar²,

Shahriar³

2018

Frontiers in Optics / Laser Science

Self Cite

View full text Add to dashboard Cite

In a conventional atomic interferometer employing N atoms, the phase sensitivity is at the standard quantum limit: 1/ √ N . Using spin-squeezing, the sensitivity can be increased, either by lowering the quantum noise or via phase amplification, or a combination thereof. Here, we show how to increase the sensitivity, to the Heisenberg limit of 1/N , while increasing the quantum noise by √ N , thereby suppressing by the same factor the effect of excess noise. The proposed protocol makes use of a Schrödinger Cat state representing a mesoscopic superposition of two collective states of N atoms, behaving as a single entity with an N -fold increase in Compton frequency. The resulting N -fold phase magnification is revealed by using atomic state detection instead of collective state detection. We also show how to realize an atomic clock based on such a Schrödinger Cat state, with an N -fold increase in the effective transition frequency. We also discuss potential experimental constraints for implementing this scheme, using one axis twist squeezing employing the cavity feedback scheme, and show that the effects of cavity decay and spontaneous emission are highly suppressed due to the N -fold phase magnification. We find that even for a modest value of the cavity cooperativity parameter that should be readily accessible experimentally, the maximum improvement in sensitivity is very close to the ideal limit, for as many as ten million atoms.PACS numbers: 06.30. Gv, 03.75.Dg, 37.25.+k Using the fact that Ȯ = tr(ρÔ) for any operatorÔ, it

show abstract

Section: A Conventional Atomic Clock and Collective State Atomic Clockmentioning

confidence: 68%

Section: A Conventional Atomic Clock and Collective State Atomic Clockmentioning

confidence: 99%

Section: A Conventional Atomic Clock and Collective State Atomic Clockmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Increasing Sensitivity of an Atom Interferometer to the Heisenberg Limit using Enhanced Quantum Noise

Fang¹,

Sarkar²,

Shahriar³

2018

Frontiers in Optics / Laser Science

Self Cite

View full text Add to dashboard Cite

show abstract

“…The extremely narrow resonances produced in the COSAIN may also help advance the field of spin squeezing [25][26][27][28], which in turn is useful for approaching the Heisenberg limit in precision metrology. Recently, we have also proposed a collective state atomic clock, which employs the principle of collective excitation of atomic ensemble, and exhibits a similar narrowing in signal fringe [29].…”

mentioning

confidence: 99%

N-atom collective-state atomic interferometer with ultrahigh Compton frequency and ultrashort de Broglie wavelength, withNreduction in fringe width

et al. 2015

Self Cite

View full text Add to dashboard Cite

We describe a collective state atomic interferometer (COSAIN) with the signal fringe as a function of phase-difference or rotation narrowed by √ N compared to a conventional interferometer -N being the number of atoms -without entanglement. This effect arises from the interferences among collective states, and is a manifestation of interference at a Compton frequency of ten nonillion Hz, or a de Broglie wavelength of 4.5 femtometer, for N = 10 6 and v = 1 m/s. The population of the collective state of interest is detected by a null measurement scheme, in which an event corresponding to detection of zero photons corresponds to the system being in that particular collective state. The signal is detected by collecting fluorescence through stimulated Raman scattering of Stokes photons, which are emitted predominantly against the direction of the probe beam, for a high enough resonant optical density. The sensitivity of the ideal COSAIN is found to be given by the standard quantum limit. However, when detection efficiency and collection efficiency are taken into account, the detection scheme of the COSAIN increases the quantum efficiency of detection significantly in comparison to a typical conventional Raman atomic interferometer employing fluorescence detection, yielding a net improvement in stability by as much as a factor of 10. We discuss how the inhomogeneities arising from the non-uniformity in experimental parameters affect the COSAIN signal. We also describe an alternate experimental scheme to enhance resonant optical density in a COSAIN by using cross-linearly polarized counter-propagating Raman beams.

show abstract

High-Compton-frequency, parity-independent, mesoscopic Schrödinger-cat-state atom interferometer with Heisenberg-limited sensitivity

2018

Self Cite

View full text Add to dashboard Cite

We present a protocol for an atomic interferometer that reaches the Heisenberg Limit (HL), within a factor of ∼ √ 2, via collective state detection and critical tuning of one-axis twist spin squeezing. It generates a Schrödinger cat (SC) state, as a superposition of two extremal collective states. When this SC interferometer is used as a gyroscope, the interference occurs at an ultrahigh Compton frequency, corresponding to a mesoscopic single object with a mass of N m, where N is the number of particles in the ensemble, and m is the mass of each particle. For 87 Rb atoms, with N = 10 6 , for example, the intereference would occur at a Compton frequency of ∼ 2 × 10 31 Hz. Under this scheme, the signal is found to depend critically on the parity of N . We present two variants of the protocol. Under Protocol A, the fringes are narrowed by a factor of N for one parity, while for the other parity the signal is zero. Under Protocol B, the fringes are narrowed by a factor of N for one parity, and by a factor of √ N for the other parity. Both protocols can be modified in a manner that reverses the behavior of the signals for the two parities. Over repeated measurements under which the probability of being even or odd is equal, the averaged sensitivity is smaller than the HL by a factor of ∼ √ 2 for both versions of the protocol. We describe an experimental scheme for realizing such an atomic interferometer, and discuss potential limitations due to experimental constraints imposed by the current state of the art, for both collective state detection and oneaxis-twist squeezing. We show that when the SC interferometer is configured as an accelerometer, the effective two-photon wave vector is enhanced by a factor of N , leading to the same degree of enhancement in sensitivity. We also show that such a mesoscopic single object can be used to increase the effective base frequency of an atomic clock by a factor of N , with a sensitivity that is equivalent to the HL, within a factor of ∼ √ 2.

show abstract

N−atomcollective-state atomic clock withN−foldincrease in effective frequency andN−<

Cited by 7 publications

References 23 publications

Increasing Sensitivity of an Atom Interferometer to the Heisenberg Limit using Enhanced Quantum Noise

Increasing Sensitivity of an Atom Interferometer to the Heisenberg Limit using Enhanced Quantum Noise

N-atom collective-state atomic interferometer with ultrahigh Compton frequency and ultrashort de Broglie wavelength, withNreduction in fringe width

High-Compton-frequency, parity-independent, mesoscopic Schrödinger-cat-state atom interferometer with Heisenberg-limited sensitivity

Contact Info

Product

Resources

About