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It is well known that instantons are classical topological solutions existing in the context of quantum field theories that lie behind the standard model of particles. To provide a better understanding for the dynamical nature of…

High Energy Physics - Theory · Physics 2015-08-05 Fatma Aydogmus

Emerging possibilities for creating and studying novel plasma regimes, e.g. relativistic plasmas and dense systems, in a controlled laboratory environment also requires new modeling tools for such systems. This brings motivation for…

Quantum Physics · Physics 2015-05-30 F. A. Asenjo , J. Zamanian , M. Marklund , G. Brodin , P. Johansson

The non-Hermitian quadratic oscillator studied by Swanson is one of the popular $PT$-symmetric model systems. Here a full classical description of its dynamics is derived using recently developed metriplectic flow equations, which combine…

Quantum Physics · Physics 2015-10-06 Eva-Maria Graefe , Hans Jürgen Korsch , Alexander Rush , Roman Schubert

We provide an alternative approach to relativistic dynamics based on the Feshbach projection technique. Instead of directly studying the Dirac equation, we derive a two-component equation for the upper spinor. This approach allows one to…

Quantum Physics · Physics 2016-10-21 Da-Wei Luo , P. V. Pyshkin , Ting Yu , Hai-Qing Lin , J. Q. You , Lian-Ao Wu

We study the structure of quantum states for a binary mixture of spin-1 atomic Bose-Einstein condensates. In contrast to collision between identical bosons, the s-wave scattering channel between inter-species does not conform to a fixed…

Quantum Gases · Physics 2010-03-11 Z. F. Xu , Jie Zhang , Yunbo Zhang , L. You

Numerical evidence for a new dynamical mechanism of elementary particle mass generation has been found by lattice simulation in a simple, yet highly non-trivial SU(3) gauge model where a SU(2) doublet of strongly interacting fermions is…

High Energy Physics - Lattice · Physics 2018-11-27 Roberto Frezzotti , Giancarlo Rossi

We present a superconvergent Kolmogorov-Arnold-Moser type of perturbation theory for time-dependent Hamiltonians. It is strictly unitary upon truncation at an arbitrary order and not restricted to periodic or quasiperiodic Hamiltonians.…

Quantum Physics · Physics 2007-05-23 D. Daems , A. Keller , S. Guérin , H. -R. Jauslin , O. Atabek

We introduce a general framework for realizing $\mathcal{PT}$-like phase transitions in non-Hermitian systems without imposing explicit parity--time ($\mathcal{PT}$) symmetry. The approach is based on constructing a Hamiltonian as the…

Optics · Physics 2025-11-18 Jacob L. Barnett , Ramy El-Ganainy

The effect of the electric field on the creation of spin 1/2 particles from vacuum in the (1+1) dimensional de-Sitter space-time is studied. The Dirac equation with a constant electric field is solved by introducing an unitary…

General Relativity and Quantum Cosmology · Physics 2015-05-01 S. Haouat , R. Chekireb

We investigate the parametric amplification of the zero-point fluctuations in the spin modes of a two-component Bose-Einstein condensate, triggered by the dynamical evolution of the condensate density. We first make use of a Thomas-Fermi…

Quantum Gases · Physics 2021-10-04 Salvatore Butera , Iacopo Carusotto

The effect of dipolar and exchange interactions within pairs of paramagnetic electronic states on Pauli-blockade-controlled spin-dependent transport and recombination rates during magnetic resonant spin excitation is studied numerically…

Materials Science · Physics 2013-04-24 M. E. Limes , J. Wang , W. J. Baker , S. -Y. Lee , B. Saam , C. Boehme

Parity-time ($PT$)-symmetric Hamiltonians exhibit non-unitary dynamical evolution while maintaining real spectra, and offer unique approaches to quantum sensing and entanglement generation. Here we present a method for simulating the…

Quantum Physics · Physics 2026-01-15 Maryam Abbasi , Koray Aydogan , Anthony W. Schlimgen , Kade Head-Marsden

A system of interacting spins that are under the influence of spin-polarized currents can be described using a complex functional, or a non-Hermitian (NH) Hamiltonian. We study the dynamics of two exchange-coupled spins on the Bloch sphere.…

Mesoscale and Nanoscale Physics · Physics 2023-04-12 Stavros Komineas

We address the problem of identifying the (nonstationary) quantum systems that admit supersymmetric dynamical invariants. In particular, we give a general expression for the bosonic and fermionic partner Hamiltonians. Due to the…

Quantum Physics · Physics 2009-11-07 Ali Mostafazadeh

We describe the formation of charge- and spin-density patterns induced by spin-selective photoexcitations of interacting fermionic systems in the presence of a microstructure. As an example, we consider a one-dimensional Hubbard-like system…

Strongly Correlated Electrons · Physics 2021-04-26 Thomas Köhler , Sebastian Paeckel , Constantin Meyer , Salvatore R. Manmana

The aim of this paper is to illustrate both analytically and numerically the interplay of two fundamentally distinct non-Hermitian mechanisms in a deep subwavelength regime. Considering a parity-time symmetric system of one-dimensional…

Optics · Physics 2025-10-01 Habib Ammari , Silvio Barandun , Ping Liu , Alexander Uhlmann

Optical instabilities in moving media are linked to a spontaneous parity-time symmetry breaking of the system. It is shown that in general the time evolution of the electromagnetic waves in moving media is determined by a non-Hermitian…

Optics · Physics 2015-06-19 M. G. Silveirinha

We study electron-positron pair creation {from} the Dirac vacuum induced by a strong and slowly varying electric field (Schwinger effect) which is superimposed by a weak and rapidly changing electromagnetic field (dynamical pair creation).…

High Energy Physics - Theory · Physics 2008-11-26 Ralf Schützhold , Holger Gies , Gerald Dunne

A pseudo su(1,1)-algebra is formulated as a possible deformation of the Cooper-pair in the su(2)-algebraic many-fermion system. With the aid of this algebra, it is possible to describe behavior of individual fermions which are generated as…

Nuclear Theory · Physics 2014-05-07 Y. Tsue , C. Providencia , J. da Providencia , M. Yamamura

We propose an experimental scheme to simulate the fractionalization of particle number by using a one-dimensional spin-orbit coupled ultracold fermionic gas. The wanted spin-orbit coupling, a kink-like potential, and a…

Quantum Gases · Physics 2012-12-19 Dan-Wei Zhang , L. -B. Shao , Zheng-Yuan Xue , Hui Yan , Z. D. Wang , Shi-Liang Zhu