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Related papers: Quantum coherence induced by magnons

200 papers

The first law of thermodynamics imposes not just a constraint on the energy-content of systems in extreme quantum regimes, but also symmetry-constraints related to the thermodynamic processing of quantum coherence. We show that this…

Quantum Physics · Physics 2015-04-15 Matteo Lostaglio , Kamil Korzekwa , David Jennings , Terry Rudolph

Quantum coherence associated with the superpositions of two different sets of eigenbasis vectors has been regarded as essential in thermodynamics. It is found that coherent factors can be determined by writing observables as an expansion in…

Quantum Physics · Physics 2022-01-31 Jingyi Chen , Guozhen Su , Jincan Chen , Shanhe Su

Quantifying entanglement is a work in progress which is important for the active field of quantum information and computation. A measure of bipartite pure state entanglement is proposed here, named entanglement coherence, which is…

Quantum Physics · Physics 2022-02-15 Neha Pathania , Tabish Qureshi

We introduce a procedure based on quantum expectation values of measurement observables to characterize quantum coherence. Our measure allows one to quantify coherence without having to perform tomography of the quantum state, and can be…

Quantum coherence is an essential ingredient in quantum information processing and plays a central role in emergent fields such as nanoscale thermodynamics and quantum biology. However, our understanding and quantitative characterization of…

We derive quantum kinetic equations for fermions in a homogeneous time-dependent background in presence of decohering collisions, by use of the Schwinger-Keldysh CTP-formalism. The quantum coherence (between particles and antiparticles) is…

High Energy Physics - Phenomenology · Physics 2009-03-24 Matti Herranen , Kimmo Kainulainen , Pyry Matti Rahkila

In this paper we introduce a simple procedure for computing the macroscopic quantum behaviour of periodic quantum systems in the high energy regime. The macroscopic quantum coherence is ascribed to a one-particle state, not to a condensate…

Quantum Physics · Physics 2015-06-17 A. Martín-Ruiz , J. Bernal , Adrián Carbajal-Domínguez

The notion of a macroscopic quantum state must be pinned down in order to assess how well experiments probe the large-scale limits of quantum mechanics. However, the issue of quantifying so-called quantum macroscopicity is fraught with…

Quantum Physics · Physics 2025-03-12 Benjamin Yadin , Matteo Fadel

An infinity magnon coupling term is introduced into the Holstein-Primakoff transformed forms of the Heisenberg ferromagnetic and antiferromagnetic models of any spin $s$ to rigorously remove the unphysical magnon states. This term makes the…

Condensed Matter · Physics 2007-05-23 Bang-Gui Liu , Gerd Czycholl

We study a simplified Heisenberg spin model in order to clarify the idea of decoherence in closed quantum systems. For this purpose, we define a new concept: the decoherence function \Xi(t), which describes the dynamics of decoherence in…

Quantum Physics · Physics 2007-05-23 Olavi Dannenberg

The meaning of statistical experiments with single microsystems in quantum mechanics is discussed and a general model in the framework of non-relativistic quantum field theory is proposed, to describe both coherent and incoherent…

Quantum Physics · Physics 2009-10-30 L. Lanz , B. Vacchini

It is shown that quantum-type coherence, leading to indeterminism and interference of probabilities, may in principle exist in the absence of the Planck constant and a Hamiltonian. Such coherence is a combined effect of a symmetry (not…

Quantum Physics · Physics 2007-05-23 Y. Orlov

We investigate quantum coherence in a hybrid cavity magnomechanical system incorporating a squeezed-magnon drive. By analyzing the Gaussian quantum coherence of the cavity, magnonic, and mechanical subsystems, as well as the total system…

By numerically exact calculations of spin-1/2 antiferromagnetic Heisenberg models on small clusters, we demonstrate that quantum entanglement between subsystems $A$ and $B$ in a pure ground state of a whole system $A+B$ can induce thermal…

Quantum Physics · Physics 2020-10-20 Kazuhiro Seki , Seiji Yunoki

Coherence and entanglement are fundamental properties of quantum systems, promising to power the near future quantum computers, sensors and simulators. Yet, their experimental detection is challenging, usually requiring full reconstruction…

Quantum Physics · Physics 2017-08-01 Graeme Smith , John A. Smolin , Xiao Yuan , Qi Zhao , Davide Girolami , Xiongfeng Ma

Macroscopic quantum coherence oscillations in mesoscopic antiferromagnets may appear when the anisotropy potential creates a barrier between the antiferromagnetic states with opposite orientations of the Neel vector. This phenomenon is…

Quantum Physics · Physics 2011-08-04 Marius Grigorescu , Mahi R. Singh

We explore the quantum information resources within bipartite pure and mixed states of the quantum spin-1 Heisenberg dimer system, considering some interesting factors such as the $l_{1}$-norm of quantum coherence, relative coherence,…

Quantum Physics · Physics 2025-01-31 Fadwa Benabdallah , M. Y. Abd-Rabbou , Mohammed Daoud , Saeed Haddadi

In thermodynamics, quantum coherences - superpositions between energy eigenstates - behave in distinctly nonclassical ways. Recently mathematical frameworks have emerged to account for these features and have provided a range of novel…

Quantum Physics · Physics 2018-04-26 Hyukjoon Kwon , Hyunseok Jeong , David Jennings , Benjamin Yadin , M. S. Kim

Coherent superposition states of a mesoscopic quantum object play a major role in our understanding of the quantum to classical boundary, as well as in quantum-enhanced metrology and computing. However, their practical realization and…

We define correlational (von Neumann) entropy for an individual quantum state of a system whose time-independent hamiltonian contains random parameters and is treated as a member of a statistical ensemble. This entropy is representation…

chao-dyn · Physics 2013-01-16 Valentin V. Sokolov , B. Alex Brown , Vladimir Zelevinsky