Article
Physics, Multidisciplinary
Stefano Chessa, Vittorio Giovannetti
Summary: This article introduces multi-level amplitude damping channels that generalize concepts in quantum information theory to finite-dimensional quantum systems, and computes the quantum and private classical capacities associated with these channels. By exploiting degradability, data-processing inequalities, and channel isomorphism, the authors extend the set of models whose capacity can be computed known so far.
COMMUNICATIONS PHYSICS
(2021)
Article
Mathematics, Applied
Mounir Afilal, Mohamed Alahyane, Baowei Feng, Abdelaziz Soufyane
Summary: This paper investigates the long-time behavior of solutions for a transmission problem of Timoshenko beam with memory. The study reveals that the stability of the system holds for a larger class of relaxation functions and achieves a higher decay rate than previously reported in the literature. Numerical tests are also conducted to validate the theoretical findings.
ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND PHYSIK
(2022)
Article
Chemistry, Physical
Jing Sun, Oriol Vendrell
Summary: This letter investigates the observed modification of thermal chemical rates in Fabry-Perot cavities and explains the mechanism behind the reduction in transmission coefficient and rate due to friction caused by cavity-reactor coupling. The authors evaluate the transmission coefficient and identify conditions for rate acceleration using an ab initio potential energy surface for the cis-trans isomerization of HONO.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Mathematics, Applied
Zhiqing Liu, Zhong Bo Fang
Summary: This paper investigates a transmission problem of viscoelastic wave equations with degenerate nonlocal damping. The global well-posedness of the problem is proved using Faedo-Galerkin technique and the multiplier method. Meanwhile, by introducing a new Lyapunov functional, the optimal explicit and general energy decay results are established.
ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND PHYSIK
(2023)
Article
Engineering, Electrical & Electronic
Dunbar Paul Birnie IV, Christopher Cheng, Emina Soljanin
Summary: We develop new methods to quantify the impact of photon detector imperfections on secret key rates in Time-Entanglement based Quantum Key Distribution (QKD). We investigate photon detection timing jitter, detector downtime, and dark photon counts, and show how each affects the achievable secret key rate differently. Our results provide a tool for experimentalists to predict their systems' secret key rate given the detector specifications.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2023)
Article
Quantum Science & Technology
Anjali Dhiman, S. Balakrishnan
Summary: This study investigates the quantum version of the cop and robber game implemented on a quantum circuit in the presence of a noisy environment. Various noise models are applied to the initial quantum state, and the fidelity of the affected quantum states is analyzed. The findings suggest that the noise in the quantum network can be suppressed by using a certain set of entangling operators, with amplitude damping being completely eliminated. However, phase damping cannot be suppressed by any specific entangling operators, and phase-flip damping and bit-flip damping cause the entanglement sudden death in the quantum state. Therefore, the existence of suitable entangling operators is indicated for noise control in quantum networks.
QUANTUM INFORMATION PROCESSING
(2022)
Article
Mathematics
Yun Mao, Yiwu Zhu, Yijun Wang, Ying Guo
Summary: This paper proposes a multi-participant secret key sharing scheme based on continuous variable quantum communication, which uses a local local oscillator to avoid potential attacks and improve the performance in terms of the maximal transmission distance.
Article
Chemistry, Multidisciplinary
Jinjun Ding, Chuanpu Liu, Yuejie Zhang, Vijaysankar Kalappattil, Rui Yu, Uppalaiah Erugu, Jinke Tang, Haifeng Ding, Hua Chen, Mingzhong Wu
Summary: The study found that an Ag spacer between the alpha-Sn film and NiFe film can enhance the damping of the NiFe film, potentially related to the topologically nontrivial surface states of the alpha-Sn film. These results suggest that the topological Dirac semimetal alpha-Sn may have promising applications in spintronics.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Engineering, Mechanical
Kiran Jacob, Aditya Suryadi Tan, Thomas Sattel, Manfred Kohl
Summary: A hybrid damper concept combining magnetorheological fluid (MRF) and shape memory alloy (SMA) has been proposed. The performance of different MRF-SMA configurations has been investigated, demonstrating the complementarity of operation between MRF and SMA dampers, resulting in improved damping performance and reduced energy consumption.
Article
Multidisciplinary Sciences
Qiuge Zhang, Samira M. Azarin, Casim A. Sarkar
Summary: In this study, the authors achieved rational control of DNA attachment site sequence to predictably modulate site-specific recombination rates using quantitative high-throughput experiments and machine learning. This research provides an important tool for gene circuit design in synthetic biology.
NATURE COMMUNICATIONS
(2022)
Article
Biochemistry & Molecular Biology
Kristine S. Ojala, Scott P. Ginebaugh, Man Wu, Evan W. Miller, Gloria Ortiz, Manuel Covarrubias, Stephen D. Meriney
Summary: Research shows that the main mechanism of action of 3,4-DAP at the neuromuscular junction is through acting on Kv channels to mediate AP broadening and enhance transmitter release.
JOURNAL OF BIOLOGICAL CHEMISTRY
(2021)
Article
Physics, Multidisciplinary
Arindam Mitra, Himanshu Badhani, Sibasish Ghosh
Summary: Applications of the quantum switch on quantum channels have been a hot topic. In this work, we find that some useless channels can provide useful communication under the action of a quantum switch for tasks like quantum random access codes and quantum steering. We also demonstrate the usefulness of the quantum switch in preventing coherence loss when only coherence-breaking channels are available. Furthermore, we show that by concatenating a useless channel with another suitable quantum channel and subsequently using the switch, useful communication can be achieved.
Article
Quantum Science & Technology
Eun Oh, Xuanying Lai, Jianming Wen, Shengwang Du
Summary: The promise of universal quantum computing requires scalable control interactions between single or multiple qubits. Current leading candidate platforms for quantum computing, superconducting circuits, trapped ions, and neutral atom arrays, suffer from strong interaction with environmental and control noises resulting in qubit decoherence. Photons, on the other hand, have advantages of being well decoupled from the environment and having high speed and timing capabilities. This article proposes a universal distributed quantum computing scheme based on photons and atomic-ensemble-based quantum memories, showcasing the potential of a photon-atom network hybrid approach.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Materials Science, Multidisciplinary
N. L. Jobbitt, J-P R. Wells, M. F. Reid, J. J. Longdell
Summary: In this study, the full magnetic g tensors of the (6)H(5/2)Z(1) and (4)G(5/2)A(1) electronic states in Sm3+:Y2SiO5 were presented, with maximum principle g' values determined for ground and excited states at two crystallographic sites. These g tensors provide important spin Hamiltonian parameters for future magnetic and hyperfine studies of Sm3+:Y2SiO5, with potential applications in quantum information storage and communication devices.
Article
Materials Science, Multidisciplinary
Ya-Ting Lan, Ming-Liang Hu
Summary: The study reveals that in a squeezed generalized amplitude damping channel, squeezing effect suppresses decay of ASC and MSC, while memory effect can also be utilized for this purpose. On the other hand, dissipation and thermal effects induce decay of ASC and MSC in the output states.
RESULTS IN PHYSICS
(2023)
Article
Physics, Multidisciplinary
Jiaozi Wang, Giuliano Benenti, Giulio Casati, Wen-ge Wang
Summary: We study the statistical and dynamical properties of the quantum triangle map. Our numerical results show that ergodicity is a sufficient condition for spectrum and eigenfunctions to follow the prediction of random matrix theory, even when the classical dynamics underlying it is not chaotic. Additionally, we find that dynamical quantities such as the out-of-time-ordered correlator (OTOC) and the number of harmonics exhibit a growth rate that vanishes in the semiclassical limit, consistent with the classical dynamics having a zero Lyapunov exponent. These findings suggest that while spectral statistics can detect ergodicity, OTOC and the number of harmonics are diagnostics of chaos.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Physics, Multidisciplinary
Jiao Wang, Giulio Casati, Giuliano Benenti
Summary: By numerically solving the classical equations of motion in a one-dimensional model, we investigated the properties of the blackbody spectrum. Our results, which do not rely on any statistical assumption, demonstrate that the classical blackbody spectrum possesses remarkable characteristics, including a quasi-stationary state with scaling properties, consistency with the Stefan-Boltzmann law, and a high-frequency cutoff. This study serves as a preliminary step in comprehending the statistical properties of infinite-dimensional systems.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Jiaozi Wang, Barbara Dietz, Dario Rosa, Giuliano Benenti
Summary: We investigate the generation of entanglement in a two-body interacting system starting from a separable coherent state. By analyzing the system's classical dynamics, we find that the entanglement growth rate in the quasiclassical regime can be simply computed. This rate is determined by the Kolmogorov-Sinai entropy, indicating a connection between the generation of entanglement and classical complexity.
Article
Physics, Multidisciplinary
Nicola Macri, Luigi Giannelli, Elisabetta Paladino, Giuseppe Falci
Summary: Quantum state processing is a crucial tool in quantum technologies, and effective Hamiltonians derived through adiabatic elimination play a significant role in simplifying complex systems. However, these approximations often face ambiguities and difficulties, limiting their accuracy for larger systems. In this study, we propose using the Magnus expansion as a systematic tool to derive unambiguous effective Hamiltonians, which only depend on proper time coarse-graining of the exact dynamics. The accuracy of the obtained effective Hamiltonians is validated through tailored fidelities of quantum operations.
Article
Physics, Multidisciplinary
Gabriele Cenedese, Maria Bondani, Dario Rosa, Giuliano Benenti
Summary: Generating a large amount of entanglement is crucial for a quantum computer to achieve quantum advantage. This paper proposes an efficient method to generate pseudo-random quantum states with nearly maximal multipartite entanglement. The method is argued to be optimal and is used to evaluate actual superconducting (IBM's ibm_lagos) and ion trap (IonQ's Harmony) quantum processors. Despite the lower error rates of ibm_lagos in single-qubit and two-qubit operations, Harmony outperforms it due to its low error rate in state preparation and measurement as well as the all-to-all connectivity of qubits. The findings highlight the importance of qubits network architecture in generating highly entangled states.
Article
Physics, Multidisciplinary
Gabriele Cenedese, Giuliano Benenti, Maria Bondani
Summary: Characterizing and mitigating errors in current noisy intermediate-scale devices is crucial for enhancing the performance of future quantum hardware. Through full quantum process tomography of single qubits in an actual quantum processor with echo experiments, we investigated the significance of various noise mechanisms in quantum computation. Our results unveiled the dominant role of coherent errors and demonstrated the practical correction of such errors by introducing random single-qubit unitaries in the quantum circuit, leading to a notable increase in the reliability of quantum computations on real quantum hardware.
Review
Physics, Multidisciplinary
Giuliano Benenti, Davide Donadio, Stefano Lepri, Roberto Livi
Summary: Energy transfer in small nano-sized systems can be very different from that in their macroscopic counterparts due to reduced dimensionality, interaction with surfaces, disorder, and large fluctuations. We provide an overview of recent advances in understanding non-diffusive heat transfer in these systems through nonequilibrium statistical mechanics and atomistic simulations. The underlying basic properties leading to violations of standard diffusive heat transport and the effects of long-range interaction and integrability on non-diffusive transport are discussed. We also explore the applications of these features in thermal management, rectification, and improving energy conversion efficiency.
RIVISTA DEL NUOVO CIMENTO
(2023)
Article
Multidisciplinary Sciences
Fabio Cavaliere, Luca Razzoli, Matteo Carrega, Giuliano Benenti, Maura Sassetti
Summary: This work investigates the performance of hybrid thermal machines that can simultaneously perform multiple tasks. Optimal working conditions for a three-terminal quantum thermal machine are characterized and identified, with the working medium being a quantum harmonic oscillator coupled to three heat baths. The study demonstrates efficient operation in both pure and hybrid modes, with the ability to switch between different operational modes by adjusting the driving frequency. The proposed setup also shows potential as a high-performance transistor.
Article
Physics, Multidisciplinary
Luca Razzoli, Fabio Cavaliere, Matteo Carrega, Maura Sassetti, Giuliano Benenti
Summary: In the pursuit of high-performance quantum thermal machines, considering fluctuations at the quantum level is crucial in addition to finding optimal thermodynamic efficiency. This paper investigates the thermodynamic uncertainty relations for a quantum thermal machine with a quantum harmonic oscillator as the working medium, connected to two thermal baths, with one of them being dynamically coupled. The study demonstrates that by adjusting parameters, the machine can function as both a quantum engine and refrigerator, achieving significant efficiency and low fluctuations.
EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS
(2023)
Article
Physics, Multidisciplinary
Fabio Cavaliere, Matteo Carrega, Giulio De Filippis, Vittorio Cataudella, Giuliano Benenti, Maura Sassetti
Summary: We discuss the possibility of realizing a heat engine by dynamically modulating the couplings between the quantum working medium and thermal reservoirs and identify suitable environments for optimizing its efficiency.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Ilia Khomchenko, Henni Ouerdane, Giuliano Benenti
Summary: The control of thermal fluxes in electronic circuits at mesoscale and nanoscale can be achieved using thermal diodes. This study proposes using a superconductor-insulator-superconductor (SIS) junction under an oscillating voltage to control the heat flow. Theoretical models suggest a sharp rise in the rectification coefficient, up to R approximate to 500.
Article
Physics, Fluids & Plasmas
Giuliano Benenti, Giulio Casati, Fabio Marchesoni, Jiao Wang
Summary: A dynamical model of a highly efficient heat engine is proposed, where an applied temperature difference maintains the motion of particles around a circuit consisting of two asymmetric narrow channels, in one of which the current flows against the applied thermodynamic forces. Numerical simulations and linear-response analysis suggest that, in the absence of frictional losses, the Carnot efficiency can be achieved in the thermodynamic limit.
Article
Physics, Multidisciplinary
L. Giannelli, J. Rajendran, N. Macri, G. Benenti, S. Montangero, E. Paladino, G. Falci
Summary: Ultrastrong coupling in superconducting circuit QED architectures allows for faster operations in the development of quantum technologies, although it also increases sensitivity to new kinds of intrinsic errors. By using optimal control methods, a resilient protocol against the main source of errors arising from the interplay of the dynamical Casimir effect with cavity losses is found.
NUOVO CIMENTO C-COLLOQUIA AND COMMUNICATIONS IN PHYSICS
(2022)
Article
Physics, Fluids & Plasmas
Vahid Shaghaghi, G. Massimo Palma, Giuliano Benenti
Summary: This study examines the statistical distribution of ergotropy and efficiency in a single-qubit battery and a single-qubit Otto engine fueled by random collisions. The interactions between the qubit and two reservoirs are described using a collision model of open system dynamics, revealing fluctuations in ergotropy, heat, and work that decrease with the size of the qudits in the hot reservoir. Although the mean macroscopic efficiency of the Otto engine remains the same, the distribution of efficiencies does not support finite moments, resulting in a discrepancy between the mean efficiency and the macroscopic efficiency.
Article
Quantum Science & Technology
Matteo Carrega, Loris Maria Cangemi, Giulio De Filippis, Vittorio Cataudella, Giuliano Benenti, Maura Sassetti
Summary: This study investigates the thermodynamic properties of quantum systems far from equilibrium, particularly when the system is strongly coupled to its environment or when memory effects cannot be neglected. The researchers find that by modulating the system-environment couplings, it is possible to perform thermodynamic tasks, such as extracting heat from a cold reservoir and realizing an ideal heat rectifier.
