Article
Physics, Multidisciplinary
Xinfang Li, Jianning Liu, Osei Seth, Heng-Na Xiong, Qing-Shou Tan, Yixiao Huang
Summary: The study proposes a simple scheme to achieve persistent spin-nematic squeezing in a spinor Bose-Einstein condensate by rapidly turning off the external magnetic field at the moment when maximal spin-nematic squeezing occurs. It is observed that the optimal squeezing can be maintained in a nearly fixed direction, with a significant enhancement possible through the use of appropriate initial magnetic fields. Additionally, a spin-mixing interferometer is constructed to utilize the quantum correlation of the squeezed state, resulting in a significantly enhanced phase sensitivity for the interferometer.
COMMUNICATIONS IN THEORETICAL PHYSICS
(2022)
Article
Multidisciplinary Sciences
Rosario R. Riso, Tor S. Haugland, Enrico Ronca, Henrik Koch
Summary: The authors introduce a fully consistent ab-initio method of molecular orbital theory applicable to material systems in quantum electrodynamics environments. The method can be used to predict and explain modifications of molecular properties due to cavity induced effects.
NATURE COMMUNICATIONS
(2022)
Article
Engineering, Mechanical
Kashif Ammar Yasir, Yu Chengyong, Gao Xianlong
Summary: In this study, we investigate the steady-state multi-stability of a cavity system containing spin-orbit coupled Bose-Einstein condensate. We show that the cavity photon number and atomic population exhibit multi-stable behavior, which can be tuned with system parameters. Additionally, we find the occurrence of population transitional phase for the atomic states, which can be controlled by spin-orbit coupling and Zeeman field effects.
NONLINEAR DYNAMICS
(2023)
Article
Physics, Multidisciplinary
Juan Roman-Roche, Fernando Luis, David Zueco
Summary: A system of magnetic molecules coupled to microwave cavities undergoes the equilibrium superradiant phase transition, which is experimentally observable. The coupling effect is illustrated by the vacuum-induced ferromagnetic order in a quantum Ising model and the modification of the magnetic phase diagram of Fe-8 dipolar crystals, showcasing the cooperation between intrinsic and photon-induced spin-spin interactions. Finally, a transmission experiment demonstrates the quantum electrodynamical control of magnetism in resolving the transition.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Rocio Saez-Blazquez, Daniele de Bernardis, Johannes Feist, Peter Rabl
Summary: This study addresses the possibility of generating nonperturbative corrections to the ground state of a dipole by coupling it to a strongly confined electromagnetic vacuum. Two simplified cavity QED setups are considered, providing analytic expressions for the total ground-state energy and distinguishing between electrostatic and vacuum-induced contributions. The findings suggest that the presence of high-impedance modes can significantly increase the vacuum-induced effects, opening up the possibility of nonperturbative light-matter interactions.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Multidisciplinary
Liaqat Ali, Rameez ul Islam, Muhammad Imran, Manzoor Ikram, Iftikhar Ahmad
Summary: We proposed a novel scheme to engineer maximally entangled four qubits N-photon field W-states through cavity QED technique. The scheme utilizes high-Q cavities as atomic beam splitters and mirrors for atomic Mach-Zehnder interferometer. The experimental results show that under certain conditions, the desired entangled states can be generated with high probability.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Nanoscience & Nanotechnology
Valerio Di Giulio, F. Javier Garcia de Abajo
Summary: This study demonstrates that the ponderomotive contribution to the electron-cavity interaction can create a more general set of optical states, including coherent and squeezed states. These findings have important implications for quantum information and optics applications.
Article
Physics, Applied
Ramachandrarao Yalla, K. Muhammed Shafi, Kali P. Nayak, Kohzo Hakuta
Summary: In this study, we demonstrate the creation of a one-sided cavity on an optical nanofiber using a composite method. The one-sided composite cavity is designed to enhance channeling efficiency and its coupling characteristics are validated through numerical simulations and experiments.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Beatriz Perez-Gonzalez, Alvaro Gomez-Leon, Gloria Platero
Summary: This study explores the physics of topological lattice models immersed in c-QED architectures with arbitrary coupling strength with the photon field. It proposes the use of cavity transmission as a topological marker and studies its behavior. The specific case of a fermionic Su-Schrieffer-Heeger (SSH) chain coupled to a single-mode cavity is used to illustrate the findings, which confirm that the cavity can act as a quantum sensor for topological phases. The persistence of topological features and the calculation of entanglement entropy are also discussed.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Optics
Karol Gietka
Summary: This article presents an alternative protocol for preparing critical states that benefits from critical speeding up rather than critical slowing down, achieved by moving away from the critical point. The protocol is applied to quantum Rabi model, its classical oscillator limit, and the Lipkin-Meshkov-Glick model. The adiabatic speed-up protocol is discussed in quantum metrology and compared to critical quantum metrology, showing that critical quantum metrology is a suboptimal strategy. The article concludes that systems exhibiting a phase transition are interesting in quantum technologies, but the critical point may not be the most important aspect.
Article
Quantum Science & Technology
Ronen M. Kroeze, Brendan P. Marsh, Kuan-Yu Lin, Jonathan Keeling, Benjamin L. Lev
Summary: In this work, a confocal-cavity-QED microscope is used to achieve cooperativity exceeding 110, which is comparable to the best single-mode cavities. This is made possible by the dispersive coupling to the atoms of many near-degenerate modes in the cavity, providing important insights for studying quantum many-body physics in the driven-dissipative setting.
Article
Physics, Multidisciplinary
Si-Yuan Bai, Jun-Hong An
Summary: The study proposes a new scheme to generate stable spin squeezing without relying on spin-spin coupling or coherent driving on TLSs. By incorporating the mediation role of the common waveguide and squeezed-reservoir engineering technique, the scheme exhibits advantages in the scaling relation of the spin squeezing parameter with the number of TLSs, potentially offering certain advantages in quantum sensing applications.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Thomas Bilitewski, Luigi De Marco, Jun-Ru Li, Kyle Matsuda, William G. Tobias, Giacomo Valtolina, Jun Ye, Ana Maria Rey
Summary: In this study, a bulk fermionic dipolar molecular gas confined in a two-dimensional geometry in the quantum degenerate regime is examined. By utilizing two rotational states of the molecules, a spin 1/2 degree of freedom is encoded. A long-range interacting XXZ model is derived to describe the many-body spin dynamics of the molecules, leading to robust dynamics and generation of entanglement despite the presence of finite temperature, dephasing, and chemical reactions. The system behaves close to the collective limit, providing insights on implementing time reversal and enhanced metrological sensing protocols through the internal state structure.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Yotam Shapira, Sapir Cohen, Nitzan Akerman, Ady Stern, Roee Ozeri
Summary: In this study, we enhance the fidelity and robustness of entangling gates in quantum computers by introducing spin-dependent squeezing.
PHYSICAL REVIEW LETTERS
(2023)
Article
Optics
Long-Gang Huang, Xuanchen Zhang, Yanzhen Wang, Zhenxing Hua, Yuanjiang Tang, Yong-Chun Liu
Summary: Spin squeezing is crucial for quantum metrology and quantum information science, but its generation faces challenges due to the lack of squeezing interactions in existing physical systems. In this study, we propose a universal scheme to generate spin squeezing in coupled spin models with collective spin-spin interactions. We can transform the coupled spin interactions into squeezing interactions and achieve extreme squeezing with Heisenberg-limited measurement precision scaling as 1/N for N particles. Only constant and continuous driving fields are required, making it accessible for current realistic experiments. This work greatly expands the systems capable of generating Heisenberg-limited spin squeezing, with broad applications in quantum precision measurement.
Article
Physics, Multidisciplinary
Simon B. Jaeger, Tom Schmit, Giovanna Morigi, Murray J. Holland, Ralf Betzholz
Summary: We present a general approach to derive Lindblad master equations for subsystems coupled to dissipative bosonic modes. We apply this approach to the dissipative Dicke model and successfully predict the Dicke phase transition and quantum metastability. The performance of our formalism is validated by comparing with exact diagonalization and numerical integration results.
PHYSICAL REVIEW LETTERS
(2022)
Editorial Material
Automation & Control Systems
Marco M. Nicotra, Jieqiu Shao, Joshua Combes, Anne Cross Theurkauf, Penina Axelrad, Liang-Ying Chih, Murray Holland, Alex A. Zozulya, Catie K. LeDesma, Kendall Mehling, Dana Z. Anderson
IEEE CONTROL SYSTEMS MAGAZINE
(2023)
Article
Physics, Multidisciplinary
Luca Lepori, Andrea Trombettoni, Domenico Giuliano, Johannes Kombe, Jorge Yago Malo, Andrew J. Daley, Augusto Smerzi, Maria Luisa Chiofalo
Summary: We discuss the conditions under which multipartite entanglement in mixed quantum states can be characterized using only two-point connected correlation functions, as is the case for pure states. However, these conditions are more severe compared to pure states. We were able to identify some interesting cases, such as when the one-point correlations in each possible decomposition of the density matrix have point-independence, or when the operators in the correlations are (semi-)positive/negative defined.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2023)
Article
Multidisciplinary Sciences
Jorge Yago Malo, Guido Marco Cicchini, Maria Concetta Morrone, Maria Luisa Chiofalo
Summary: Humans and animals can sense the number of items in their environment at birth, suggesting the emergence of number sense in simple populations of neurons. However, current modelling literature has struggled to provide a simple architecture for this task. We present a quantum spin model that encodes numerosity in the spectrum, showing the ability to capture the perceptual characteristics of numerosity and reproduce Weber's law.
Article
Quantum Science & Technology
Raphael Kaubruegger, Athreya Shankar, Denis V. Vasilyev, Peter Zoller
Summary: We study the multiparameter sensing of 2D and 3D vector fields using SU(2) quantum interferometry in the Bayesian framework. We develop a method to determine the optimal quantum sensor, which sets the fundamental limit on precision for simultaneously estimating multiple parameters with an N-atom sensor. We propose sensors with limited entanglement capabilities that outperform sensors without entanglement and approach the optimal quantum sensor in terms of performance.
Article
Optics
Allison L. Carter, Sean R. Muleady, Athreya Shankar, Jennifer F. Lilieholm, Bryce B. Bullock, Matthew Affolter, Ana Maria Rey, John J. Bollinger
Summary: In this study, we theoretically investigate the impact of spontaneous emission on quantum gate operations with trapped-ion ground-state Zeeman qubits in a high magnetic field. We compare the performance of two types of gates and explore different operating points. Our results show that both gate types can achieve similar performance at high magnetic fields.
Article
Optics
John Drew Wilson, Simon B. Jaeger, Jarrod T. Reilly, Athreya Shankar, Maria Luisa Chiofalo, Murray J. Holland
Summary: The creation and manipulation of quantum entanglement is crucial for improving precision measurements. This study introduces a method that goes beyond one-axis twisting to generate squeezing and entanglement across two distinct degrees of freedom. By using a nonlinear Hamiltonian to generate dynamics in SU(4), more rich context of quantum entanglement is achieved.
Article
Physics, Multidisciplinary
Maria Bondani, Maria Luisa Chiofalo, Elisa Ercolessi, Chiara Macchiavello, Massimiliano Malgieri, Marisa Michelini, Oxana Mishina, Pasquale Onorato, Filippo Pallotta, Sara Satanassi, Alberto Stefanel, Claudio Sutrini, Italo Testa, Giacomo Zuccarini
Summary: This paper describes an extracurricular course on quantum physics and quantum technologies applications, which was conducted online and evaluated for its effectiveness. The results show that the course effectively improved students' understanding of quantum physics and quantum technology.
Article
Quantum Science & Technology
Mauro Chiarotti, Jonathan N. Tinsley, Satvika Bandarupally, Shamaila Manzoor, Michele Sacco, Leonardo Salvi, Nicola Poli
Summary: Atom interferometry on optical clock transitions is crucial for achieving high sensitivities, but it is important to meet stringent requirements on laser frequency noise for large momentum transfer. The operational fidelity is fundamentally constrained by imperfect pulse fidelity in the presence of noise.
Article
Optics
Jarrod T. Reilly, Simon B. Jaeger, John Cooper, Murray J. Holland
Summary: This study proposes a method to adiabatically control an atomic ensemble using a decoherence-free subspace (DFS) within a dissipative cavity. By interfering the emission amplitude of the ensemble with an injected field, a specific eigenstate of the system's Lindblad jump operators can be engineered. Unlike previous adiabatic DFS proposals, this scheme allows for the creation of a DFS in the presence of collective decoherence, enabling faster state preparation.
Article
Optics
Gage W. Harmon, Jarrod T. Reilly, Murray J. Holland, Simon B. Jaeger
Summary: The study presents a theoretical description of a lasing scheme for atoms with three internal levels in a V configuration interacting with an optical cavity, demonstrating a closed lasing cycle on a dipole-forbidden transition. Utilizing stability analysis and mean-field Floquet method, the lasing threshold, emission frequency, and bistable solutions are determined. The research sheds light on the complex physics of cold atom lasers with narrow line transitions through simple methods.
Article
Education & Educational Research
Maria Luisa Chiofalo, Caterina Foti, Marisa Michelini, Lorenzo Santi, Alberto Stefanel
Summary: Teaching quantum physics is challenging, but quantum games can help overcome obstacles and enhance students' understanding and engagement. A pilot study involving high-school students showed that the combination of a teaching module and a game effectively improved students' grasp of quantum concepts and their experience of quantum behavior. The use of quantum game tools in a learning environment has multiple benefits, including increasing awareness, complementing other languages of thinking, and improving intervention efficiency and effectiveness.
EDUCATION SCIENCES
(2022)
Article
Physics, Multidisciplinary
John P. Bartolotta, Simon B. Jager, Jarrod T. Reilly, Matthew A. Norcia, James K. Thompson, Graeme Smith, Murray J. Holland
Summary: In the field of light-matter interactions, it is commonly assumed that classical light fields interacting with quantum particles undergo negligible changes and do not contain information about the particles. This study develops a Gedanken experiment to investigate the validity of this assumption, quantifying the alteration of the light field and the transfer of entropy using Bayesian inference. The results show that in the strong coupling limit, information about the particle state can be fully encoded in the light field.
PHYSICAL REVIEW RESEARCH
(2022)