Bulletin of the American Physical Society
51st Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
Volume 65, Number 4
Monday–Friday, June 1–5, 2020; Portland, Oregon
Session J02: Quantum OpticsLive

Hide Abstracts 
Chair: Olivier Pfister, University of Virginia Room: D133134 
Wednesday, June 3, 2020 2:00PM  2:12PM Live 
J02.00001: Twobeam coupling in quantumcorrelated images MengChang Wu, Nicholas Brewer, Rory Speirs, Kevin Jones, Paul Lett We study the effects of 2beam coupling on quantum imaging in a fourwave mixing medium. In our previous work [1] we demonstrated sub10 Hz bright intensitydifference squeezed light from dualseeded fourwave mixing (4WM) in Rb vapor. In this work we have observed excess noise at frequencies below the natural linewidth of Rb due to the twobeam coupling mechanism [2]. This noise, which destroys the quantum correlations between the beams, can be avoided by making sure that the input seeds do not intersect each other in the pump region. The problem is similar in the case of generating quantumcorrelated images. We can eliminate this problem by imaging the seed into the 4WM region, rather than focusing it. That is, amplifying in the imaging plane rather than the Fourier plane. With sub10 Hz squeezed light and "crosstalk" free imaging, we are closer to taking pixelbypixel quantum correlated images via 4WM with a CCD camera. [1] M.C. Wu, et al., Optics Express 27, 4769 (2019). [2] M. Kauranen, et al., Phys. Rev. A 50, R929 (1994). [Preview Abstract] 
Wednesday, June 3, 2020 2:12PM  2:24PM Live 
J02.00002: Imaging Spatial Quantum Noise Suppression Savannah Cuozzo, Nikunjkumar Prajapati, Lior Cohen, Elisha Siddiqui, Jon Dowling, Irina Novikova, Eugeniy Mikhailov We will present our study on spatial quantum noise decomposition which allows us to image different quantum noise structures and manipulate the beam to optimize overall squeezing. Precision measurements are limited by intrinsic noise because of quantum uncertainty. This noise appears in two different quadratures  phase and amplitude quadratures. The noise quadratures obey the Heisenberg uncertainty principle, which sets the standard quantum limit (SQL), so we can reduce noise in one of these quadratures (at the expense of increasing noise in the other). Light with noise suppression in one of the quadratures below the SQL is called squeezed light. Squeezed light yields significant improvement of signaltonoise ratios in many applications including precision metrology and optical communication. Squeezing, however, is not generated uniformly throughout the beam. To use these squeezed beams to our maximal advantage, we are developing methods that allow for spatial mode decomposition of the quantum beam. Advances in spatial detection and control of squeezed beams is of particular interest to optical communication technologies since it would allow quantum information transfer on individual spatial modes. [Preview Abstract] 
Wednesday, June 3, 2020 2:24PM  2:36PM Live 
J02.00003: SteadyState Superradiant Laser with an Atomic Beam Source Haonan Liu, Simon Jäger, John Cooper, Athreya Shankar, Travis Nicholson, Murray Holland Steadystate superradiant lasers based on incoherent pumping have been shown to be promising candidates for coherent light sources of ultranarrow linewidth. However, the incoherent pumping process can lead to many experimental difficulties due to radiative heating and other adverse effects. Here we propose a new type of superradiant laser based on a hot atomic beam. This design may be more straightforward to realize in experiments than in situ repumping, but is also rich in novel collective quantum physics. Specifically, we consider three models of the superradiant beam laser in this work. We first study a benchmark ``tight collimated model'' and show, both theoretically and numerically, that the superradiant beam laser is indeed a \textit{superradiant laser} in terms of first and second order temporal correlations and superradiant emission. We then explore a monovelocity model to show quantum phase synchronization as the transverse velocities of atoms decrease below a phase transition point. Finally we show that with a hot atomic beam, the system will recover the benchmark superradiance below the phase transition point. [Preview Abstract] 
Wednesday, June 3, 2020 2:36PM  2:48PM Live 
J02.00004: Direct Characterization of EinsteinPodolskyRosen EnergyTime Entangled Narrowband Biphotons Yefeng Mei, Yiru Zhou, Shanchao Zhang, Jianfeng Li, Kaiyu Liao, Hui Yan, ShiLiang Zhu, Shengwang Du The EinsteinPodolskyRosen (EPR) energytime entangled photons (biphotons) are of great interest for longdistance quantum communication and quantum network. Direct characterization of EPR energytime entanglement requires joint correlation measurements in both time and frequency domains and remains a challenge. In this work, we produce narrowband (1.8 MHz) biphotons from spontaneous fourwave mixing in cold 85Rb atoms. The temporal correlation and uncertainties are measured by commercial singlephoton counting modules. We map the biphoton joint spectrum and energy uncertainties using a narrow linewidth (72 kHz) optical cavity. We obtain the joint frequencytime uncertainty product as low as 0.063$+$/0.0044, which not only violates the separability criterion but also satisfies the continuous variable EPR steering inequality. Our result of joint frequencytime uncertainty product is significantly smaller than the previously reported values and pushes its lower bound a step closer to zero. The work was supported by the Hong Kong Research Grants Council (Project No. 16304817), and the William Mong Institute of Nano Science and Technology (Project No. WMINST19SC05). [Preview Abstract] 
Wednesday, June 3, 2020 2:48PM  3:00PM Live 
J02.00005: Can a photon saturate an atom without being absorbed? Josiah Sinclair, Daniela Angulo, Kyle Thompson, Kent BonsmaFisher, Aephraim Steinberg As a resonant photon passes through a cloud of twolevel atoms, it weakly saturates the atomic transition, modifying the index of refraction of the cloud, which can be measured as a nonlinear crossphase shift (XPS) on a second, offresonant beam. In cases where a photon is observed at a detector on the far side of the cloud, one might conclude that it had not been absorbed and that there should therefore be no XPS. In our experiment on absorptive optical nonlinearities in cold $^{\mathrm{85}}$Rb, we use postselection to isolate the phase shift imparted by a transmitted photon. We find that despite not having been absorbed, transmitted photons impart a significant fraction (0.77$+$/0.17) of the nonlinear XPS of the average incident photon, raising questions about the relationship between atomic excitation, absorption, and scattering at the fully quantized level. [Preview Abstract] 
Wednesday, June 3, 2020 3:00PM  3:12PM Live 
J02.00006: Frequency Tunable Squeezed Light through Atomic State Dressing of FourWave Mixing Saesun Kim, Alberto M. Marino The reduced noise properties of squeezed light make it an ideal quantum state for quantumenhanced metrology based on optical sensors. To extend its applicability to atomicbased sensors, squeezed light that can be tuned to and around atomic resonance is needed. While we have previously shown that it is possible to generate resonant twomode squeezed light using fourwave mixing (FWM) in atomic Rb vapor, its tunabilty was limited by atomic absorption. To overcome this limitation, we have designed a vacuum chamber with internal electrodes that can be used to apply a large electric field to a rubidium vapor cloud. Our system can support electric fields of the order of 10 MV/m for a Rb number density of $\sim 10^{16}/{\rm m}^{3}$, which leads to a DC stark energy level shift of 500 MHz for the D1 transition. Furthermore, for the number densities required for the FWM process ($\sim 10^{18}/{\rm m}^{3}$) the system can support electric fields of the order of 7 MV/m. This allows us to tune the frequency of the squeezed light by as much as 250 MHz while preserving a level of 4dB of squeezing. This dressed energy level approach can also enable a tunable singlemode vacuum squeezed state source via polarized selfrotation and a tunable narrowband optical filter near atomic resonance. [Preview Abstract] 
Wednesday, June 3, 2020 3:12PM  3:24PM On Demand 
J02.00007: Hanbury BrownTwiss Correlations for a Driven Superatom Huy Nguyen, Jacob Lampen, Alisher Duspayev, Hikaru Tamura, Paul Berman, Alex Kuzmich Hanbury BrownTwiss interference and stimulated emission, two fundamental processes in atomic physics, have been studied in a wide range of applications in science and technology. We study interference effects that occur when a weak probe is sent through a gas of twolevel atoms that are prepared in a singly excited collective (Dicke or ``superatom'') state and for atoms prepared in a factorized state. We measure the timeintegrated secondorder correlation function of the output field as a function of the delay between the input probe field and radiation emitted by the atoms and find that, for the Dicke state, is twice as large for zero delay as it is for large delays, while for the product state, this ratio is equal to 3/2. The results agree with those of a theoretical model in which any effects related to stimulated emission are totally neglectedthe coincidence counts measured in our experiment arise from Hanbury BrownTwiss interference between the input field and the field radiated by the atoms. [Preview Abstract] 
Wednesday, June 3, 2020 3:24PM  3:36PM On Demand 
J02.00008: Phasematched scattering from an atomic array Hikaru Tamura, Huy Nguyen, Paul Berman, Alex Kuzmich We investigate phasematched scattering from an array of atoms that are confined in optical tweezers in one and twodimensional geometries. For a linear chain, we observe phasematched reflective scattering in a cone about the symmetry axis of the array that scales as the square of the number of atoms in the chain. For two linear chains of atoms, the phasematched reflective scattering is enhanced or diminished as a result of Bragg scattering. Such scattering can be used for mapping collective states within an array of neutral atoms onto propagating light fields and for establishing quantum links between separated arrays. [Preview Abstract] 
Wednesday, June 3, 2020 3:36PM  3:48PM 
J02.00009: Experimental Mapping of Correlations of Structured Two Mode Squeezed Twin Beams Nikunjkumar Prajapati, Savannah Cuozzo, Lior Cohen, Elisha Siddiqui, Jonathan Dowling, Eugeniy Mikhailov, Irina Novikova We experimentally explore spatial and temporal correlations between twomode squeezed twin beams which carry diverse spatial mode structure and are generated in hot Rb vapor via fourwave mixing. The phase matching conditions in FWM describe coherence areas in which correlations are expected, even for diverse mode structures. However, light with complicated structure is never truly single mode in nature and the coherence areas are complicated. In order to probe correlations of varying modes between the twin beams, we utilize machine learning and MonteCarlo methods. This knowledge could allow for further enhancement of quantum imaging and quantum communications. [Preview Abstract] 
Wednesday, June 3, 2020 3:48PM  4:00PM 
J02.00010: Theory of an onchip Josephson quantum michomaser Chenxu Liu, Maria Mucci, Xi Cao, Michael Hatridge, David Pekker Solidstate superconducting qubit systems are one of the most promising systems to achieve quantum computing. One of the shortcomings of this architecture is the lack of an onchip coherent microwave source. To solve this problem, we explore the feasibility of building a Josephson micromaser powered by tunable superconducting transmon qubit(s) (which serve as an artificial threelevel atom). Specifically, we explain how to engineer a system composed of two qubits (one a conventional transmon, the other a transmon with a SNAIL element) to construct an element that behaves like a 3level atom coupled to a dissipative bath. We construct a master equation description of the maser and estimate its properties, like its coherence time, and their dependence on the pump power, pump noise, cavity widths, etc. We show that the linewidth of the micromaser approaches the SchawlowTownes (ST) limit with feasible experimental parameters. We further notice that the nonlinear couplings between the superconducting qubit and the cavity can suppress the linewidth beyond the ST limit. Finally, we note that the possibility for highly nonlinear devices in the microwave regime allows our maser to generate quantum (i.e. nonGaussian) light. [Preview Abstract] 
Follow Us 
Engage
Become an APS Member 
My APS
Renew Membership 
Information for 
About APSThe American Physical Society (APS) is a nonprofit membership organization working to advance the knowledge of physics. 
© 2021 American Physical Society
 All rights reserved  Terms of Use
 Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 207403844
(301) 2093200
Editorial Office
1 Research Road, Ridge, NY 119612701
(631) 5914000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 200452001
(202) 6628700