Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

AIP conference proceedings

Multiphoton- and simultaneous conjugate Ramsey-Borde atom interferometers

Holger Müller, Sheng‐wey Chiow, Sven Herrmann, Steven Chu, Alfredo Macı́as, Cláus Lämmerzahl, Abel Camacho

Published Jan 1, 2008• 1 citation
Publisher

Abstract

We report on our experiment to measure h/M, the ratio of the Planck constant to the mass of Cs atoms, and thereby the fine‐structure constant. The target accuracy is 1 part per billion or better. We focus on two recent milestones: (i) The first realization of atom interferometers based on light‐pulse beam splitters that transfer the momentum of up to 12 photon pairs, which increases the useful signal (matter wave phase shift) by a factor of 144 compared to the beam splitters used in the best present atom interferometers. Moreover, they lead to a cancellation of important systematic effects. (ii) The first realization of a simultaneous pair of conjugate Ramsey‐Bordé interferometers. In these, the relative sign of the inertial term is reversed so that it can be cancelled. Simultaneous operation means that this holds for a time‐dependent inertial term (vibrations) too, which promises a substantial improvement in the signal to noise ratio.

DOI
10.1063/1.2902792

Related papers

Noise-Immune Conjugate Large-Area Atom Interferometers

Sheng‐wey Chiow, Sven Herrmann, Steven Chu +1 more

We present a pair of simultaneous conjugate Ramsey-Bordé atom interferometers using large (20variant Planck's over 2pik)-momentum transfer beam splitters, where variant Planck's over 2pik is the photon momentum. Simultaneous operation allows for common-mode rejection of vibrational noise. This allows us to surpass the enclosed space-time area of previous interferometers with a splitting of 20variant Planck's over 2pik by a factor of 2500. Using a splitting of 10variant Planck's over 2pik, we demonstrate a 3.4 ppb resolution in the measurement of the fine structure constant. Examples for applications in tests of fundamental laws of physics are given.

arXiv:0901.1819•Physical Review Letters•Jul 28, 2009•69 citations

Offset simultaneous conjugate atom interferometers

Weicheng Zhong, Richard H. Parker, Zachary Pagel +2 more

Correlating the signals from simultaneous atom interferometers has enabled some of the most precise determinations of fundamental constants. Here, we show that multiple simultaneous interferometers with strategically chosen initial conditions (offset simultaneous conjugate interferometers) can provide multichannel readouts that measure or suppress specific signals and systematic effects. We create two pairs of simultaneous conjugate interferometers and precisely control the offset between them with Bragg diffraction and Bloch oscillations. This allows us to cancel the effect of acceleration gradients, a major systematic effect in many atom interferometry measurements. It also reduces the undesired diffraction phase from Bragg diffraction beam splitters by a factor of 6. This work paves the way for measurements of the fine-structure constant below the 10-part-per-trillion level. It can also be generalized for isotope-mass-ratio measurements.

arXiv:1901.03487•Physical Review A•May 14, 2020•1 citation

Measuring the fine structure constant using multiphoton atom interferometry

Holger Müller, Sheng‐wey Chiow, Sven Herrmann +1 more

24-photon Bragg diffraction of matter waves by light pulses increases the splitting between the arms of Ramsey-Borde or Mach-Zehnder atom interferometers, leading to up to 144-fold sensitivity. Simultaneous conjugate interferometers reject noise.

Frontiers in Optics•Jan 1, 2008•0 citations

Atom Interferometers with Scalable Enclosed Area

Holger Müller, Sheng‐wey Chiow, Sven Herrmann +1 more

Bloch oscillations (i.e., coherent acceleration of matter waves by an optical lattice) and Bragg diffraction are integrated into light-pulse atom interferometers with large momentum splitting between the interferometer arms, and hence enhanced sensitivity. Simultaneous acceleration of both arms in the same internal states suppresses systematic effects, and simultaneously running a pair of interferometers suppresses the effect of vibrations. Ramsey-Bordé interferometers using four such Bloch-Bragg-Bloch beam splitters exhibit 15% contrast at 24variant Planck's over 2pik splitting, the largest so far (variant Planck's over 2pik is the photon momentum); single beam splitters achieve 88variant Planck's over 2pik. The prospects for reaching 100 s of variant Planck's over 2pik and applications such as gravitational wave sensors are discussed.

arXiv:0903.4192•Physical Review Letters•Jun 18, 2009•137 citations

Compton clock and recoil frequency measurements using a large momentum transfer atom interferometer

Pei-Chen Kuan

Light-pulse atom interferometers have been used as quantum inertial sensors and for precision tests of fundamental laws of physics. For higher contrast, we apply conjugate Ramsey-Borde interferometers to cancel out vibrational noise and top mirror tilting to compensate the Coriolis force. For higher sensitivity, we implement Bragg diffraction and Bloch oscillations for large momentum transfer to increase the enclosed area of our atom interferometer. We also utilize Raman sideband cooling in our experimental setup, which increases the overall signal about twentyfold, and increases the contrast by suppressing the thermal expansion of the atom cloud.By combining measurements of recoil frequency and a frequency comb, we present the first clock referenced to the mass of a single particle. The rest mass of a particle defines its Compton frequency, mc^2/h through relativity and quantum mechanics, and thereby sets a fundamental timescale. Our clock stabilizes a 10 MHz radio frequency signal to a certain fraction of the cesium Compton frequency. Future work could result in an elementary particle (electron) or even antimatter (antihydrogen) clock, opening up new ways to test CPT symmetry and the equivalence principle. We also present our progress towards a new determination of the fine structure constant. The fine structure constant value obtained by our cesium Compton clock measurement is about three times better compared with the earlier cesium recoil frequency result. After combining Bragg diffraction and Bloch oscillations, we achieved 0.33 ppb sensitivity (0.66 ppb uncertainty of the recoil frequency measurement) in 6 hours, which is about two times better than the previous best recoil frequency measurement. The leading systematic effect is also reduced by a factor of 2.75.

•Jan 1, 2013•0 citations

Precision Measurement in Atom Interferometry Using Bragg Diffraction

Brian Estey

We experimentally and theoretically study Bragg diffraction as a tool for large-momentum transfer beam splitters in atom interferometry. A theoretical framework is developed to quantify the diffraction phase systematic caused by Bragg diffraction and experiments are performed to confirm these predictions using a Ramsey-Bord\\'e atom interferometer. We then develop methods to systematically cancel and reduce the diffraction phase systematic by carefully selecting Bragg diffraction parameters and utilizing Bloch oscillations. These techniques are then applied to an ongoing precision measurement of $h/m_\\text{Cs}$ for cesium, with the end goal of measuring the fine structure constant $\\alpha$. We demonstrate a high contrast simultaneous conjugate Ramsey-Bord\\'e interferometer using 5th order Bragg diffraction and 25 common mode Bloch oscillations which achieves $2.5\\times 10^6$ radians of phase. We also demonstrate an interferometer with a statistical uncertainty of $\\delta \\alpha/\\alpha=0.25$ ppb after 25 hours of integration time that has diffraction phase systematic error of around 1 ppb. Other sources of systematic uncertainty are also thoroughly explored and determined to better than 0.1 ppb. The techniques and theories developed in this thesis will hopefully help enable future precision measurements based on Bragg diffraction.

•Jan 1, 2016•2 citations
We report on our experiment to measure h/M, the ratio of the Planck constant to the mass of Cs atoms, and thereby the fine‐structure constant. The target accuracy is 1 part per billion or better. We focus on two recent milestones: (i) The first realization of atom interferometers based on light‐pulse beam splitters that transfer the momentum of up to 12 photon pairs, which increases the useful signal (matter wave phase shift) by a factor of 144 compared to the beam splitters used in the best present atom interferometers. Moreover, they lead to a cancellation of important systematic effects. (ii) The first realization of a simultaneous pair of conjugate Ramsey‐Bordé interferometers. In these, the relative sign of the inertial term is reversed so that it can be cancelled. Simultaneous operation means that this holds for a time‐dependent inertial term (vibrations) too, which promises a substantial improvement in the signal to noise ratio.
We present a pair of simultaneous conjugate Ramsey-Bordé atom interferometers using large (20variant Planck's over 2pik)-momentum transfer beam splitters, where variant Planck's over 2pik is the photon momentum. Simultaneous operation allows for common-mode rejection of vibrational noise. This allows us to surpass the enclosed space-time area of previous interferometers with a splitting of 20variant Planck's over 2pik by a factor of 2500. Using a splitting of 10variant Planck's over 2pik, we demonstrate a 3.4 ppb resolution in the measurement of the fine structure constant. Examples for applications in tests of fundamental laws of physics are given.
Correlating the signals from simultaneous atom interferometers has enabled some of the most precise determinations of fundamental constants. Here, we show that multiple simultaneous interferometers with strategically chosen initial conditions (offset simultaneous conjugate interferometers) can provide multichannel readouts that measure or suppress specific signals and systematic effects. We create two pairs of simultaneous conjugate interferometers and precisely control the offset between them with Bragg diffraction and Bloch oscillations. This allows us to cancel the effect of acceleration gradients, a major systematic effect in many atom interferometry measurements. It also reduces the undesired diffraction phase from Bragg diffraction beam splitters by a factor of 6. This work paves the way for measurements of the fine-structure constant below the 10-part-per-trillion level. It can also be generalized for isotope-mass-ratio measurements.
Bloch oscillations (i.e., coherent acceleration of matter waves by an optical lattice) and Bragg diffraction are integrated into light-pulse atom interferometers with large momentum splitting between the interferometer arms, and hence enhanced sensitivity. Simultaneous acceleration of both arms in the same internal states suppresses systematic effects, and simultaneously running a pair of interferometers suppresses the effect of vibrations. Ramsey-Bordé interferometers using four such Bloch-Bragg-Bloch beam splitters exhibit 15% contrast at 24variant Planck's over 2pik splitting, the largest so far (variant Planck's over 2pik is the photon momentum); single beam splitters achieve 88variant Planck's over 2pik. The prospects for reaching 100 s of variant Planck's over 2pik and applications such as gravitational wave sensors are discussed.
Light-pulse atom interferometers have been used as quantum inertial sensors and for precision tests of fundamental laws of physics. For higher contrast, we apply conjugate Ramsey-Borde interferometers to cancel out vibrational noise and top mirror tilting to compensate the Coriolis force. For higher sensitivity, we implement Bragg diffraction and Bloch oscillations for large momentum transfer to increase the enclosed area of our atom interferometer. We also utilize Raman sideband cooling in our experimental setup, which increases the overall signal about twentyfold, and increases the contrast by suppressing the thermal expansion of the atom cloud.By combining measurements of recoil frequency and a frequency comb, we present the first clock referenced to the mass of a single particle. The rest mass of a particle defines its Compton frequency, mc^2/h through relativity and quantum mechanics, and thereby sets a fundamental timescale. Our clock stabilizes a 10 MHz radio frequency signal to a certain fraction of the cesium Compton frequency. Future work could result in an elementary particle (electron) or even antimatter (antihydrogen) clock, opening up new ways to test CPT symmetry and the equivalence principle. We also present our progress towards a new determination of the fine structure constant. The fine structure constant value obtained by our cesium Compton clock measurement is about three times better compared with the earlier cesium recoil frequency result. After combining Bragg diffraction and Bloch oscillations, we achieved 0.33 ppb sensitivity (0.66 ppb uncertainty of the recoil frequency measurement) in 6 hours, which is about two times better than the previous best recoil frequency measurement. The leading systematic effect is also reduced by a factor of 2.75.
We experimentally and theoretically study Bragg diffraction as a tool for large-momentum transfer beam splitters in atom interferometry. A theoretical framework is developed to quantify the diffraction phase systematic caused by Bragg diffraction and experiments are performed to confirm these predictions using a Ramsey-Bord\\'e atom interferometer. We then develop methods to systematically cancel and reduce the diffraction phase systematic by carefully selecting Bragg diffraction parameters and utilizing Bloch oscillations. These techniques are then applied to an ongoing precision measurement of $h/m_\\text{Cs}$ for cesium, with the end goal of measuring the fine structure constant alpha\\alphaalpha. We demonstrate a high contrast simultaneous conjugate Ramsey-Bord\\'e interferometer using 5th order Bragg diffraction and 25 common mode Bloch oscillations which achieves 2.5times1062.5\\times 10^62.5times106 radians of phase. We also demonstrate an interferometer with a statistical uncertainty of deltaalpha/alpha=0.25\\delta \\alpha/\\alpha=0.25deltaalpha/alpha=0.25 ppb after 25 hours of integration time that has diffraction phase systematic error of around 1 ppb. Other sources of systematic uncertainty are also thoroughly explored and determined to better than 0.1 ppb. The techniques and theories developed in this thesis will hopefully help enable future precision measurements based on Bragg diffraction.