Article
Physics, Multidisciplinary
Lukas Rammelmueller, David Huber, Matija Cufar, Joachim Brand, Hans-Werner Hammer, Artem G. Volosniev
Summary: We present a numerical analysis of spin-2 fermions in a one-dimensional harmonic potential in the presence of a magnetic point-like impurity. Ground-state level crossing between sectors with different fermion parities is observed already for a few particles, which indicates a few-body precursor of a quantum phase transition. This picture is further supported by analyzing density-density correlations in momentum space. Finally, we discuss the experimental realization of this system in existing cold-atoms platforms.
Article
Optics
Bishal Parajuli, Daniel Pecak, Chih-Chun Chien
Summary: We investigate binary atomic boson-fermion mixtures confined in one-dimensional box potentials using few-body theory and mean-field many-body theory. Different correlations and structures can be observed by tuning inter- and intra-species interactions. Both few-body and many-body calculations demonstrate the presence of miscible phase, three-chunk phase separation, and two-chunk phase separation. Phase diagrams are presented to illustrate the regions where different structures exist. The analysis of two-body correlation functions in few-body theory provides information relevant to many-body calculations or experiments. The healing lengths of both species in the phase-separation regime are extracted from many-body density profiles, and their scaling behavior is explained by an energy-competition argument.
Article
Physics, Multidisciplinary
Mitchell J. Knight, Harry M. Quiney, Andy M. Martin
Summary: This paper describes the variational determination of the two-fermion reduced density matrix for harmonically trapped, ultracold few-fermion systems in one dimension with equal spin populations. The problem is formulated as a semi-definite program subject to N-representability conditions. The ground-state energies, density, pair-correlation function, and eigenvalues of the 2-RDM are found using an augmented Lagrangian method. The results show that this method accurately describes the salient features of the systems and has the potential to handle larger systems.
NEW JOURNAL OF PHYSICS
(2022)
Article
Physics, Multidisciplinary
G. Bougas, S. Mistakidis, P. Giannakeas, P. Schmelcher
Summary: The few-body correlations emerging in two-dimensional harmonically trapped mixtures were comprehensively investigated, revealing the formation of atom-dimer and trap states, in addition to trimers. The Tan's contacts of these eigenstates were studied, showing enhanced correlations in trimer states compared to other eigenstates. An upper bound was found in the two-body contact of atom-dimer and trap states, while no such bound existed in the three-body contact.
NEW JOURNAL OF PHYSICS
(2021)
Article
Chemistry, Physical
Ruixuan Zhu, Xiaohang Fang, Chao Xu, Majie Zhao, Huangwei Zhang, Martin Davy
Summary: In this study, one-dimensional detonations in ammonia/hydrogen-air mixtures were numerically investigated. Pulsating instabilities and periodic coupling and decoupling of shock waves were observed. The oscillatory mode of detonation was determined by the ratio of driver pressure and initial pressure. The effects of hydrogen dilution and mixture equivalence ratio on pulsating detonations were also examined.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Engineering, Geological
Peng Jing, Hossein Nowamooz
Summary: This study proposes a theoretical framework for calculating the permanent deformation of unsaturated granular materials. By separating the Soil Water Retention Curve into three linear phases and developing unique curves based on normalized suction values, the proposed approach successfully replicates experimental results. The effect of deviatoric stress on permanent deformation is also considered, and the approach is applied in a finite difference code for simulation.
ENGINEERING GEOLOGY
(2021)
Article
Physics, Multidisciplinary
Alexander N. Gorban, Bogdan Grechuk, Evgeny M. Mirkes, Sergey Stasenko, Ivan Y. Tyukin
Summary: This work introduces a method for correcting Artificial Intelligence errors using external devices and new decisions for fast, non-iterative corrections, especially suitable for legacy AI systems. Through new stochastic separation theorems, corrections can be made to data with fine-grained structure.
Article
Physics, Applied
Yu-Hsun Chu, Hou-Ju Chen, Shin-Ye Lee, Christopher John Butler, Li-Syuan Lu, Han Yeh, Wen-Hao Chang, Minn-Tsong Lin
Summary: Researchers have studied the electronic structures of different types of MoS2 steps using scanning tunneling microscopy and spectroscopy. They found that each type has unique bandgap features, which can be modified by choosing different edge conditions.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Multidisciplinary
Madhumita Sarkar, Mainak Pal, Arnab Sen, Krishnendu Sengupta
Summary: We numerically analyze spin-1/2 fermions in a one-dimensional harmonic potential with a magnetic point-like impurity. Even for a few particles, we observe ground state level crossings between different fermion parities. We interpret this as a few-body precursor to a quantum phase transition, where the impurity breaks a Cooper pair. This interpretation is supported by analyzing density-density correlations in momentum space. Finally, we discuss the experimental realization of the system using existing cold-atom platforms.
Article
Mathematics
Hyung Jun Choi, Seonghak Kim
Summary: This article investigates the initial-boundary value problem for a class of equations of non-convex elastodynamics in one space dimension. It is proven that there are infinitely many local-in-time Lipschitz weak solutions to this problem, which exhibit immediate fine-scale oscillations of the strain whenever the range of the initial strain intersects with the elliptic regime. As a result, these solutions are nowhere C1 in the part of the space-time domain with fine phase mixtures, but are smooth in the other part of the domain.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2023)
Article
Materials Science, Multidisciplinary
Robert A. Jones, Max A. Metlitski
Summary: This paper investigates the boundary problem of root SPT phase with symmetry group G = Z(2) x Z(2)(f) in (2+1)D fermion SPTs. By processing the bulk model, it derives a one-dimensional lattice model for the boundary and finds that it realizes an Ising conformal field theory with a stable gapless boundary state.
Article
Mechanics
Alessandro Ferrari
Summary: This paper presents new analytical solutions for one-dimensional compressible viscous adiabatic flow of an ideal gas, considering both constant and variable heat flux. The importance of determining correct transformations of variables and identifying the physical variable of kinetic energy per unit mass is highlighted. The dimensionless representation of the solutions emphasizes the fundamental role of dimensionless groups in problems with viscous dissipation and heat transfer. The validated analytical solutions extend Fanno's and Rayleigh's models and have been discussed in physical terms.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Optics
Jun-Cong Zheng, Peng-Bo LI
Summary: We investigated the transmission of single and two photons in a one-dimensional waveguide coupled with a Kerr micro-ring resonator and a polarized quantum emitter. The non-reciprocal behavior of the system is attributed to the unbalanced coupling between the quantum emitter and the resonator, causing a phase shift. Our analytical solutions and numerical simulations showed that the nonlinear resonator scattering leads to energy redistribution of the two photons through the bound state. In the two-photon resonance state, the polarization of the correlated photons is locked to their propagation direction, resulting in non-reciprocity. Hence, our configuration can function as an optical diode.
Article
Physics, Multidisciplinary
M. C. Gordillo
Summary: The behavior of mixtures of Yb-173 and Yb-171 fermionic isotopes loaded in 1D optical lattices was studied using diffusion Monte Carlo technique to solve the Schrodinger equation. Different cluster behaviors were observed with varying interactions between pairs of fermions, showing both metallic-like and insulator-like states in the clusters.
NEW JOURNAL OF PHYSICS
(2021)
Article
Mechanics
Tribikram Gupta, Kalpana Sharma, M. Lavanyaa, Sanjay Gupta
Summary: Graphene nanoribbons (GNRs) are widely used in nanoelectronics and opto-electronics. In this study, we investigated the energy spectrum and mapping of alternate bond systems in one-dimensional and quasi one-dimensional chains. Our findings provide valuable insights for the applications of GNRs.
Article
Physics, Multidisciplinary
G. C. Katsimiga, S. Mistakidis, P. Schmelcher, P. G. Kevrekidis
Summary: This study investigates the phase diagram, stability, magnetic properties, and dynamics of nonlinear solitary wave excitations in different phases of a spinor F = 1 Bose-Einstein condensate. Various types of nonlinear excitations, such as dark-dark-bright solitons, dark-bright-bright solitons, and dark-dark-dark solitons, are found to exist in different phases with varying stability. The transitions between phases and the behavior of these solitons at finite temperatures are also explored, shedding light on the systematic production and analysis of spin transfer processes of similar waveforms observed in ultracold experiments.
NEW JOURNAL OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
S. Mistakidis, G. M. Koutentakis, F. Grusdt, H. R. Sadeghpour, P. Schmelcher
Summary: The study investigates the impurity-induced dynamics in trapped one-dimensional Bose polarons subject to radio frequency pulses, revealing various excitations and mode-couplings under different interactions, as well as spectral shifts induced by impurity-impurity correlations. The findings suggest implications for new cold-atom experiments involving external traps, RF pulses, and impurity-impurity interactions.
NEW JOURNAL OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
Jie Chen, Simeon Mistakidis, Peter Schmelcher
Summary: In this study, we investigate the polaronic properties of a single impurity immersed in a weakly interacting bosonic environment confined within a one-dimensional double-well potential using an exact diagonalization approach. We find that the occurrence of the polaron orthogonality catastrophe is signified by a vanishing residue with an increase of the impurity-bath coupling. We obtain the asymptotic configurations of the systems' ground state wave function in the strongly interacting regime by means of a Schmidt decomposition, which accounts for the observed orthogonality catastrophe of the polaron.
NEW JOURNAL OF PHYSICS
(2022)
Article
Physics, Multidisciplinary
S. Mistakidis, G. M. Koutentakis, F. Grusdt, P. Schmelcher, H. R. Sadeghpour
Summary: In this study, we investigate the formation and phase diagram of magnetic Bose polaron in a one-dimensional spinor Bose gas. The residue of magnetic polarons decreases significantly with strong impurity-spin interactions. Impurities can be utilized to manipulate spin polarization and suppress spin-spin correlations in the magnetic medium.
NEW JOURNAL OF PHYSICS
(2022)
Article
Physics, Multidisciplinary
Ansgar Siemens, Peter Schmelcher
Summary: This study investigates the classical equilibrium properties and metamorphosis of the ground state of interacting dipoles with fixed locations. The dipoles form separate intertwined chains which can be tuned by geometrical parameters, resulting in a self-similar bifurcation diagram linked to the Stern-Brocot tree and the Farey sequence.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Optics
Jie Chen, Simeon Mistakidis, Peter Schmelcher
Summary: We investigate the correlated quantum quench dynamics of a single impurity immersed in a bosonic environment confined in a one-dimensional double-well potential. By analyzing the time-evolved many-body wave function, we find that a two-fold fragmented many-body state is dynamically formed when the impurity interacts with the non-interacting bosonic bath. However, increasing the strength of the impurity-bath coupling leads to the destruction of the two-fold fragmentation due to additional inter-band excitation dynamics.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2023)
Article
Optics
I. A. Englezos, S. I. Mistakidis, P. Schmelcher
Summary: We study one-dimensional harmonically confined quantum droplets in two-component mixtures using a nonperturbative approach. In symmetric homonuclear settings, beyond-Lee-Huang-Yang correlations result in flat-top droplet configurations for decreasing intercomponent attraction or larger atom number. Asymmetric mixtures feature spatial mixing and the more strongly interacting or heavier component exhibits flat-top structures. Quenches on the harmonic trap trigger the lowest-lying collective droplet excitations, and the interaction-dependent breathing frequency shows a decreasing trend for stronger attractions. Predictions within the Lee-Huang-Yang framework are obtained. Relatively large quench amplitudes cause delocalization of the droplet, higher-lying motional excitations in its core, enhanced intercomponent entanglement, and long-range correlations. In contrast, the dipole motion remains robust. Species-selective quenches lead to dephasing or irregular dipole patterns due to intercomponent collisions.
Article
Optics
Daniel J. Bosworth, Frederic Hummel, Peter Schmelcher
Summary: We show that the recently observed long-range ion-Rydberg molecules can be split into two families with unique electronic structures resulting from the ion-induced admixture of different Rydberg nP states. We predict that these molecular states can bind additional ground-state atoms, forming charged ultralong-range Rydberg molecules with similar binding energies as nonpolar ULRMs. This has been demonstrated by considering a Rydberg atom interacting with a single ground-state atom and an ion, breaking the system's symmetry and leading to mixing between decoupled states.
Article
Optics
G. C. Katsimiga, S. I. Mistakidis, K. Mukherjee, P. Schmelcher, P. G. Kevrekidis
Summary: This paper investigates the existence, stability, and quench-induced dynamics of vortex-bright type excitations in two-dimensional harmonically confined spin-1 Bose-Einstein condensates. Linearly stable vortex-bright-vortex and bright-vortex-bright solutions occur in both antiferromagnetic and ferromagnetic spinor gases with variations in the quadratic Zeeman energy shift. The deformations of these solutions during relevant transitions are discussed, revealing that emergent instabilities can lead to pattern formation. The study also unveils spatial elongations, precessional motion, and spiraling of the nonlinear excitations when exposed to finite temperatures and crossing distinct phase boundaries via quenching of the quadratic Zeeman coefficient. Spin-mixing processes triggered by the quench result in changes in the waveform of the configurations. The findings highlight the interplay between pattern formation and spin-mixing processes in contemporary cold atom experiments.
Article
Optics
Xiang Gao, Ya-Fen Cai, Shao-Jun Li, Shou-Long Chen, Xue-Ting Fang, Qian-Ru Zhu, Lushuai Cao, Peter Schmelcher, Zhong-Kun Hu
Summary: Magnetic monopoles have been observed as quasiparticles in condensed matter and ultracold atomic systems. This study explores the interaction between monopoles and magnons in an atomic pseudospin chain. The monopole excites a virtual magnon cloud in the chain, resulting in a unique type of polaron known as the monopole-cored polaron (MCP). The magnon dressing affects the monopole hopping and leads to an antitrapping effect, enhancing the mobility of the MCP.
Article
Optics
Judith Becker, Maxim Pyzh, Peter Schmelcher
Summary: We investigate the dynamic transport of an impurity between different majority species separated in a spatially double well. The impurity transfer and storage are achieved by dynamically changing the interaction strengths between the impurity and the two majority species. We propose a simple and efficient protocol utilizing linear ramps of majority-impurity interactions at specific times to control the impurity. Our study, conducted with the multilayer multiconfiguration time-dependent Hartree method, includes analysis of single-particle densities, entanglement growth, and an effective potential description involving mean fields of the interacting components. The stability of the transport and storage properties is unexpectedly affected by interspecies correlations.
Article
Optics
Xiang Gao, Shao-Jun Li, Shou-Long Chen, Xue-Ting Fang, Qian-Ru Zhu, Xing Deng, Lushuai Cao, Peter Schmelcher, Zhong-Kun Hu
Summary: This study explores the conditions for the coexistence and interaction effects between magnetic monopoles and kinks in an atomic dipolar superlattice gas. It is found that there is a binding effect between the monopole and kink, which alters the dispersion of the kink.
Article
Optics
Friethjof Theel, Simeon Mistakidis, Kevin Keiler, Peter Schmelcher
Summary: We investigate the dynamics of two correlated impurities in a double well coupled to a one-dimensional bosonic medium. By studying the entanglement between the impurities and the medium, as well as the impurities' two-body correlations, we determine the ground-state phase diagram of the system. Our results show that the impurity structures and the intervals of existence strongly depend on the interactions between the impurities and the external confinement of the medium.
Article
Optics
A. Romero-Ros, G. C. Katsimiga, P. G. Kevrekidis, B. Prinari, G. Biondini, P. Schmelcher
Summary: This work extends earlier findings on the creation of dark soliton trains in single-component BECs to two-component BECs, and obtains analytical expressions for the DB soliton solutions produced by a general initial configuration. It is found that the size of the initial box and the amount of filling directly affect the number, size, and velocity of the solitons, while the initial phase determines the parity of the solutions.
Article
Physics, Multidisciplinary
S. Mistakidis, T. Mithun, P. G. Kevrekidis, H. R. Sadeghpour, P. Schmelcher
Summary: The study investigates the impact of intercomponent correlations beyond Lee-Huang-Yang physics on one-dimensional quantum droplets using a nonperturbative approach. The findings show that droplets exhibit Gaussian-shaped configuration with intercomponent attractive couplings, which becomes narrower with stronger intracomponent repulsion and transitions to a flat-top structure under certain conditions. Furthermore, a correlation hole is present at the balance point, and introducing mass imbalance leads to intercomponent mixing and excitation signatures.
PHYSICAL REVIEW RESEARCH
(2021)