English
Related papers

Related papers: Spin-Nematic Squeezed Vacuum in a Quantum Gas

200 papers

Entanglement can improve the measurement precision of quantum sensors beyond the shot noise limit. Neutral atoms, the basis of some of the most precise and accurate optical clocks and interferometers, do not naturally exhibit all-to-all…

Coupled optical cavities, which support normal modes, play a critical role in optical filtering, sensing, slow-light generation, and quantum state manipulation. Recent theoretical work has proposed incorporating nonlinear materials into…

We report an interaction that controls spin squeezing in a collection of spin 1/2 particles. We describe how spin squeezing can be generated and maintained in time. Our scheme can be applied to control the spin squeezing in a Bose…

Quantum Physics · Physics 2009-11-06 C. K. Law , H. T. Ng , P. T. Leung

The (pseudo-)spin degrees of freedom greatly enriches the physics of cold atoms. This is particularly so for systems with high spins (i.e., spin quantum number larger than 1/2). For example, one can construct not only the rank-1 spin…

Quantum Gases · Physics 2020-11-11 Li Chen , Yunbo Zhang , Han Pu

Squeezing a quantum state along a specific direction has long been recognized as a crucial technique for enhancing the precision of quantum metrology by reducing parameter uncertainty. However, practical quantum metrology often involves the…

Spin squeezed states are a class of entangled states of spins that have practical applications to precision measurements. In recent years spin squeezing with one-axis twisting (OAT) has been demonstrated experimentally with spinor BECs with…

Quantum Physics · Physics 2013-05-15 Chao Shen , Luming Duan

Quantum metrology employs entanglement to enhance measurement precision. The focus and progress so far have primarily centered on estimating a single parameter. In diverse application scenarios, the estimation of more than one single…

Quantum Physics · Physics 2025-07-31 Jiahao Cao , Xinwei Li , Tianwei Mao , Wenxin Xu , Li You

Spin squeezing has been explored in atomic systems as a tool for quantum sensing, improving experimental sensitivity beyond the spin standard quantum limit for certain measurements. To optimize absolute metrological sensitivity, it is…

High Energy Physics - Phenomenology · Physics 2025-02-21 Eric Boyers , Garry Goldstein , Alexander O. Sushkov

We use the vacuum Rabi splitting to perform quantum nondemolition (QND) measurements that prepare a conditionally spin-squeezed state of a collective atomic psuedo-spin. We infer a 3.4(6) dB improvement in quantum phase estimation relative…

Quantum Physics · Physics 2012-03-08 Zilong Chen , Justin G. Bohnet , Shannon R. Sankar , Jiayan Dai , James K. Thompson

We predict that exploiting spin-orbit coupling in a harmonically trapped spinor quantum gas can lead to scaling of the optimal measurement precision beyond the Heisenberg scaling. We show that quadratic scaling with the number of atoms can…

Quantum Physics · Physics 2023-03-15 Karol Gietka , Helmut Ritsch

Spin squeezing in collective atomic ensembles enables quantum-enhanced metrology by reducing noise below the standard quantum limit through nonlinear interactions. Extending the one-axis and two-axis twisting paradigms of Kitagawa and Ueda,…

Quantum Physics · Physics 2026-01-01 Chon-Fai Kam

We experimentally demonstrate an alternative method for the dynamic generation of atomic spin squeezing, building on the interplay between linear coupling and nonlinear phase evolution. Since the resulting quantum dynamics can be seen as…

Quantum Physics · Physics 2015-07-13 W. Muessel , H. Strobel , D. Linnemann , T. Zibold , B. Juliá-Díaz , M. K. Oberthaler

We examine how non-destructive measurements generate spin squeezing in an atomic Bose-Einstein condensate confined in a double-well trap. The condensate in each well is monitored using coherent light beams in a Mach-Zehnder configuration…

Quantum Physics · Physics 2021-11-30 Ebubechukwu O. Ilo-Okeke , Shinichi Sunami , Christopher J. Foot , Tim Byrnes

The quantum emulation of spin-momentum coupling (SMC), a crucial ingredient for the emergence of topological phases, is currently drawing considerable interest. In previous quantum gas experiments, typically two atomic hyperfine states were…

Quantum Gases · Physics 2016-03-01 M. A. Khamehchi , Chunlei Qu , M. E. Mossman , Chuanwei Zhang , P. Engels

We describe an experiment where spin squeezing occurs spontaneously within a standard Ramsey sequence driving a two-component Bose-Einstein condensate (BEC) of 87Rb atoms trapped in an elongated magnetic trap. Multiparticle entanglement is…

Displacement sensing is a fundamental task in metrology. However, the development of quantum-enhanced sensors that fully utilize the available degrees of freedom in many-body quantum systems remains an outstanding challenge. We propose…

We examine how to signify and quantify the mesoscopic quantum coherence of approximate two-mode NOON states and spin-squeezed two-mode Bose-Einstein condensates (BEC). We identify two criteria that verify a nonzero quantum coherence between…

Quantum Physics · Physics 2017-03-09 B. Opanchuk , L. Rosales-Zárate , R. Y. Teh , M. D. Reid

We derive spin squeezing inequalities that generalize the concept of the spin squeezing parameter and provide necessary and sufficient conditions for genuine 2-, or 3- qubit entanglement for symmetric states, and sufficient condition for…

Quantum Physics · Physics 2009-11-11 J. Korbicz , J. I. Cirac , M. Lewenstein

Bosonic two-mode squeezed states are paradigmatic entangled Gaussian states that have wide utility in quantum information and metrology. Here, we show that the basic structure of these states can be generalized to arbitrary bipartite…

Quantum Physics · Physics 2025-02-27 Mikhail Mamaev , Martin Koppenhöfer , Andrew Pocklington , Aashish A. Clerk

We study the conditions for generating spin squeezing via a quantum non-demolition measurement in an ensemble of cold 87Rb atoms. By considering the interaction of atoms in the 5S_{1/2}(F=1) ground state with probe light tuned near the D2…

Quantum Physics · Physics 2007-05-23 S. R. de Echaniz , M. W. Mitchell , M. Kubasik , M. Koschorreck , H. Crepaz , J. Eschner , E. S. Polzik