Article
Optics
Liang Mao, Yajiang Hao, Lei Pan
Summary: In this paper, the non-Hermitian skin effect (NHSE) is extended from noninteracting systems to interacting many-body systems by studying an exactly solvable non-Hermitian model, the Lieb-Liniger Bose gas with imaginary vector potential. The NHSE is characterized quantitatively through solving the Bethe ansatz equations and calculating the model's density profiles and momentum distributions. It is found that the NHSE is enhanced for bound-state solutions on the attractive side, while it shows a nonmonotonic behavior for the scattering state. This work provides an example of NHSE in exactly solvable many-body systems and suggests its extension to other non-Hermitian many-body systems, particularly integrable models.
Article
Physics, Multidisciplinary
J. Settino, N. Lo Gullo, F. Plastina, A. Minguzzi
Summary: The study introduces a method to accurately evaluate the spectral function of a gas of one-dimensional bosons, showing three main singularity lines in the spectral function under lattice confinement, with the Lieb-II mode exhibiting divergence, providing a way to probe this mode in experiments with ultracold atoms.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Applied
Yajiang Hao, Yiwang Liu, Xiangguo Yin
Summary: In this study, the correlation properties of the ground state of Tonks-Girardeau gases are investigated in momentum space. The ground state wavefunction in coordinate space is obtained using the Bose-Fermi mapping method based on the wavefunction of spin-polarized fermions. Fourier transformation is then applied to obtain the ground state wavefunction, pair correlation, and reduced one-body density matrix in momentum space. The correlations in momentum space exhibit larger values only in small momentum regions and vanish in most other regions. Additionally, the lowest natural orbital and occupation distribution in momentum space are obtained.
INTERNATIONAL JOURNAL OF MODERN PHYSICS B
(2023)
Article
Quantum Science & Technology
Thomas Fogarty, Thomas Busch
Summary: This study demonstrates that a quantum Otto cycle involving a transition of an ultracold gas between superfluid and insulating phases can outperform single particle cycles. Utilizing the energy gap and the interplay between lattice forces and particle distribution can lead to a many-body cooperative effect. Introducing an approximate shortcut to adiabaticity for efficient cycling around a critical point can help mitigate unwanted non-equilibrium dynamics.
QUANTUM SCIENCE AND TECHNOLOGY
(2021)
Article
Physics, Multidisciplinary
Bjoern Schrinski, Anders S. Sorensen
Summary: Photons strongly coupled to material systems provide a new approach to realize nonlinear optics at the level of individual photons and study the dynamics of non-equilibrium quantum many-body systems. By using a simple physical polariton-picture, we can analytically describe the dynamics of photons coupled to a one-dimensional array of two-level atoms, including polariton scattering inside the medium and reflections of polaritons from the array's edge. We show that inelastic collisions, observed in small systems, also occur in infinite systems due to the existence of multiple bands in the dispersion relation. The developed theory serves as an effective field theory for studying nonlinear optics and many-body dynamics.
NEW JOURNAL OF PHYSICS
(2022)
Article
Mechanics
Xu Wang, Peter Schiavone
Summary: In this study, the nonlinearly coupled thermoelectric problem associated with an eccentrically coated circular inhomogeneity embedded in an infinite thermoelectric matrix subjected to uniform remote electric current density and uniform remote energy flux is investigated. By using conformal mapping and analytic continuation, the continuity conditions across the two circular interfaces are enforced, and the original problem is reduced to the determination of two analytic functions. The six original analytic functions in the three phases characterizing the thermoelectric fields are obtained by determining these two analytic functions through satisfaction of the singular behaviors.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2023)
Article
Physics, Multidisciplinary
Oleksandr Marchukov, Artem G. Volosniev
Summary: In this study, the Gross-Pitaevskii equation is used to investigate acoustic emission generated in a uniform Bose gas by a static impurity, exploring the shape of the sound-wave packet and its potential in extracting impurity properties. The results are general for all one-dimensional systems and can be applied to non-atomic systems, such as analyzing light propagation in nonlinear optical media.
Article
Engineering, Civil
Mohsen K. Khalajestani, Ahsan Parvez, Stephen James Foster, Hamid Valipour, Graeme McGregor
Summary: The demand for high-strength steel in concrete structures is increasing due to its potential benefits. Various design standards are now allowing the use of higher strength steel, but more comprehensive test data is needed to ensure the confident application of high-strength concrete with HSS in columns.
ENGINEERING STRUCTURES
(2021)
Article
Mathematics
Bessem Samet, Calogero Vetro
Summary: In this study, a Cauchy viscoelastic problem perturbed by an inverse-square potential in an exterior domain of R-N is considered under a Dirichlet boundary condition. By using nonlinear capacity estimates specifically adapted to the non-local nature of the problem, the potential function, and the boundary condition, we establish sufficient conditions for the nonexistence of weak solutions.
Article
Physics, Multidisciplinary
Qingling Zhang, Weifeng Jiang
Summary: This paper focuses on the general Riemann problem for the 1-D Eulerian droplet model with a delta initial condition. By providing a global analytical solution, it addresses a gap in the literature and introduces a new type of wave, providing insights for future studies on conservation laws with source terms.
EUROPEAN PHYSICAL JOURNAL PLUS
(2021)
Article
Construction & Building Technology
Zhanzhong Yin, Bo Yang, Xiaobo Zhang
Summary: This paper proposes an improved buckling-restrained brace that can replace traditional braces by separating the links from the beams and using replaceable links. The replaceable link can confine inelastic deformation to itself and be easily replaced after earthquakes. The improved brace also acts as an energy-dissipation member to ensure the performance of the replaceable link. The seismic performance and replaceability of the structure were analyzed through tests, showing that the number and spacing of stiffeners and the length ratio of the links significantly affect the failure mode and energy-dissipation performance of the structure.
JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH
(2022)
Article
Computer Science, Interdisciplinary Applications
Hessam Fathipour, Meghdad Payan, Reza Jamshidi Chenari, Behzad Fatahi
Summary: This study focuses on the influence of inherent anisotropy on the ultimate bearing capacity of shallow foundations resting on cohesionless granular soils, showing that the failure locus generally decreases in size as the anisotropy ratio increases.
COMPUTERS AND GEOTECHNICS
(2022)
Article
Mathematics, Applied
Ma Yuanbin, Li Zhi
Summary: This paper considers a class of perturbed uncertain differential equations driven by canonical process and establishes the existence and uniqueness of the solution through the reflection principle and a successive approximation method. As an application, the existence and uniqueness of some perturbed reflected canonical process are also examined.
Article
Engineering, Civil
Yasin Onuralp Ozkilic, Elif Muge Un, Cem Topkaya
Summary: According to the AISC Seismic Provisions for Structural Steel Buildings (AISC341-16) and EC8, the inelastic rotation demand for I-shape shear links in eccentrically braced frames (EBFs) should not exceed 0.08 rad. However, numerical studies have shown that the actual inelastic rotation demands can be much higher than this limit. Additionally, these links are susceptible to low-cycle fatigue (LCF) failure which is influenced by the loading history. This paper proposes a frictional mid-spliced shear link that can increase the rotation capacity and LCF life of shear links by introducing frictional faying surfaces at the mid-length splice connection.
EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS
(2023)
Article
Engineering, Civil
Ali Mansouri
Summary: This paper proposes the use of haunched links in eccentrically braced frames to accommodate architectural considerations without undermining seismic performance. Finite element modeling, validated with experimental data, shows that the proposed haunched link has a higher inelastic rotation capacity and energy dissipation capacity than conventional links, leading to higher deformation capacity and ductility.
ENGINEERING STRUCTURES
(2021)
Article
Physics, Multidisciplinary
M. Mikkelsen, T. Fogarty, Th Busch
Summary: This study investigates the relationship between information scrambling and work statistics for short-range interacting particles in a one-dimensional harmonic trap. It finds that scrambling requires finite interactions and establishes a connection between scrambling properties and induced work fluctuations, which are directly observable in modern cold-atom experiments.
PHYSICAL REVIEW LETTERS
(2022)
Editorial Material
Physics, Multidisciplinary
Tim Keller, Thomas Fogarty, Thomas Busch
Summary: The study demonstrates that a Tonks-Girardeau gas in a Bose-Einstein condensate can transition to a crystal-like Mott state without an externally imposed lattice potential. The phase transition depends on the interspecies interaction and temperature of the TG gas and can be measured through accessible observables in cold atom experiments. An effective model was also developed to accurately describe the system in the pinned insulator state and derive the critical temperature of the transition.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
C. Campbell, J. Li, Th Busch, T. Fogarty
Summary: Supersymmetry allows for the construction of a hierarchy of Hamiltonians with common spectral properties and connected through super-potentials. The iso-spectral properties of these Hamiltonians connect the dynamics and control of different eigenstates through supersymmetric intertwining relations. In this work, we explore how this property enables the study of general dynamics, shortcuts to adiabaticity, and quantum speed limits for different states of distinct supersymmetric partner potentials using the infinite box as an example.
NEW JOURNAL OF PHYSICS
(2022)
Article
Physics, Multidisciplinary
Jean-Yves Desaules, Francesca Pietracaprina, Zlatko Papi, John Goold, Silvia Pappalardi
Summary: Recent experimental observation of weak ergodicity breaking in Rydberg atom quantum simulators has sparked interest in quantum many-body scars—eigenstates which evade thermalization at finite energy densities due to novel mechanisms that do not rely on integrability or protection by a global symmetry. In this Letter, we demonstrate that such exact many-body scars also possess extensive multipartite entanglement structure if they stem from an su(2) spectrum generating algebra. We show this analytically, through scaling of the quantum Fisher information, which is found to be superextensive for exact scarred eigenstates in contrast to generic thermal states. Furthermore, we numerically study signatures of multipartite entanglement in the PXP model of Rydberg atoms, showing that extensive quantum Fisher information density can be generated dynamically by performing a global quench experiment. Our results identify a rich multipartite correlation structure of scarred states with significant potential as a resource in quantum enhanced metrology.
PHYSICAL REVIEW LETTERS
(2022)
Article
Quantum Science & Technology
Nathan Keenan, Niall F. Robertson, Tara Murphy, Sergiy Zhuk, John Goold
Summary: In this study, we digitally simulate the quantum dynamics of a spin-21 XXZ spin chain on a noisy near-term quantum device, and extract the high temperature transport exponent at the isotropic point. By simulating the temporal decay of the relevant spin correlation function using a pseudo-random state generated by a tailored random circuit on the ibmq-montreal 27 qubit device, we observe a spin excitation on a homogeneous background. The subsequent discrete time dynamics on the device reveal an anomalous super-diffusive exponent consistent with the conjectured Kardar-Parisi-Zhang (KPZ) scaling at the isotropic point. Furthermore, we restore spin diffusion by applying an integrability breaking potential.
NPJ QUANTUM INFORMATION
(2023)
Article
Physics, Multidisciplinary
Tran Duong Anh-Tai, Mathias Mikkelsen, Thomas Busch, Thomas Fogarty
Summary: We systematically study the emergence of quantum chaos in a minimal system of one-dimensional harmonically trapped Bose-Bose mixtures by tuning the particle-particle interactions. Using improved exact diagonalization scheme, we show that one can obtain strong signatures of chaos by increasing the inter-component interaction strength and breaking the symmetry of intra-component interactions.
Article
Optics
Jake Xuereb, Steve Campbell, John Goold, Andre Xuereb
Summary: We examine the deterministic quantum computation with one-clean-qubit model (DQC1) complexity class as an open quantum system. We show that the evolution of the logical qubit in any algorithm in the complexity class can be described as an open quantum system undergoing unital dynamics. Unital quantum channels respect the Tasaki-Crooks fluctuation theorem, which is captured by the thermodynamics of the logical qubit. As an application, we investigate the equilibrium and nonequilibrium thermodynamics of the DQC1 trace estimation algorithm, revealing the impact of computational inputs and logical qubit temperature on the algorithm's quality and fluctuations experienced.
Article
Physics, Multidisciplinary
Anthony Kiely, Eoin O'Connor, Thomas Fogarty, Gabriel T. Landi, Steve Campbell
Summary: The statistics of work on a quantum system can be measured using a two-point measurement scheme. By analyzing the Shannon entropy of the work distribution, we find a general upper bound determined by the initial diagonal entropy and a quantum term related to the relative entropy of coherence. Our approach effectively captures important physical characteristics in various scenarios. In particular, we study the Aubry-Andre-Harper model and demonstrate that the entropy of the work distribution accurately reflects the physics of the localization transition, which is not evident from statistical moments.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Optics
Jose Carlos Pelayo, Karol Gietka, Thomas Busch
Summary: In distributed quantum sensing, correlations between multiple modes of a photonic system are used to improve the precision of measuring an unknown parameter. This study investigates the metrological potential of a multimode, tilted Bose-Hubbard system and demonstrates that it can achieve parameter estimation at the Heisenberg limit. By optimizing the initial state, the limit can be reached without requiring correlations between different modes. Furthermore, strategies are proposed to obtain quadratic dependence on the number of modes in a more realistic experimental setup.
Article
Physics, Multidisciplinary
Mohamed Boubakour, Thomas Fogarty, Thomas Busch
Summary: We study a minimal quantum Otto heat engine with an interacting few-body system in a harmonic trap, where the interaction strength is considered as an additional tunable parameter during the work strokes. By calculating the figures of merit of the engine as a function of temperature, we clearly show in which parameter regimes the interactions assist in engine performance. We also compare the interaction-enhanced cycle with the case where the system remains scale-invariant, studying the finite-time dynamics and the subsequent tradeoff between efficiency and power.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Optics
Fam Le Kien, Sile Nic Chormaic, Thomas Busch
Summary: This study investigates the directional dependence of the coupling between a nanofiber-guided light field and a two-level atom with an electric quadrupole transition. It is found that the absolute value of the quadrupole Rabi frequency depends on the propagation direction of the light field in certain cases. The directional dependence of the coupling leads to directional dependence of spontaneous emission into guided modes. The study also reveals that the directional dependence of the atom-field coupling in the case of quadrupole transitions is not solely due to spin-orbit coupling of light, but also involves contributions from the gradient of the spatial phase factor of the field.
Article
Physics, Multidisciplinary
Christopher Campbell, Thomas Fogarty, Thomas Busch
Summary: We study the dynamics of an ultracold quantum many-body system when quenching between two super-symmetric Hamiltonians. We show that the dynamics can be conveniently described using knowledge about the initial state only. In the case of a fermionic gas initially trapped in an infinite box potential, we observe many-body revivals when quenching to higher order supersymmetric partner potentials, with some revivals being robust at finite temperatures.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Cecilia Chiaracane, Archak Purkayastha, Mark T. Mitchison, John Goold
Summary: Understanding and controlling quantum transport in low-dimensional systems is crucial for heat management at the nanoscale. This study investigates the effect of quasiperiodic disorder, which induces fractality in the energy spectrum, on the thermal and electric conductivities of a noninteracting model. The research finds that the presence of dephasing noise enhances transport in the subdiffusive regime and leads to multiple peaks in both thermal and electric conductivities, violating the Wiedemann-Franz law. This feature can be utilized to enhance the performance of quantum thermal machines.
Article
Optics
Mark T. Mitchison, Archak Purkayastha, Marlon Brenes, Alessandro Silva, John Goold
Summary: This study proposes a scheme to measure the temperature of pure states through quantum interference, showing that even individual pure quantum states can have temperatures in completely isolated quantum systems.
