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Related papers: Nonclassicality of noisy quantum states

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We address a particular instance where open quantum systems may be used as quantum probes for an emergent property of a complex system, as the temperature of a thermal bath. The inherent fragility of the quantum probes against decoherence…

We use the non-equilibrium bosonization technique to investigate effects of the Coulomb interaction on quantum Hall edge states at filing factor nu=2, partitioned by a quantum point contact (QPC). We find, that due to the integrability of…

Mesoscale and Nanoscale Physics · Physics 2013-05-30 Ivan P. Levkivskyi , Eugene V. Sukhorukov

We consider a single harmonic oscillator coupled to a bath at zero temperature. As is well known, the oscillator then has a higher average energy than that given by its ground state. Here we show analytically that for a damping model with…

Quantum Physics · Physics 2009-11-13 ILki Kim , Guenter Mahler

We study a small quantum system (e.g. a simplified model for an atom or molecule) interacting with two bosonic or fermionic reservoirs (say, photon or phonon fields). We show that the combined system has a family of stationary states,…

Mathematical Physics · Physics 2009-11-11 M. Merkli , M. Mueck , I. M. Sigal

Viewed as approximations to quantum mechanics, classical evolutions can violate the positive-semidefiniteness of the density matrix. The nature of this violation suggests a classification of dynamical systems based on classical-quantum…

Quantum Physics · Physics 2009-11-06 Salman Habib , Kurt Jacobs , Hideo Mabuchi , Robert Ryne , Kosuke Shizume , Bala Sundaram

Considering an arbitrary, varying equation of the state parameter, the thermodynamic properties of the dark energy fluid in a semiclassical loop quantum cosmology scenario, which we consider the inverse volume modification, is studied. The…

General Relativity and Quantum Cosmology · Physics 2011-03-22 Kui Xiao , Jian-Yang Zhu

An uncertainty relation for the number and phase of a single-mode field state is derived. It is then used to find a lower bound on the phase noise of a classical state. Any state that violates this condition is nonclassical. An example of…

Quantum Physics · Physics 2023-09-18 Mark Hillery

Cooling mechanical resonators is of great importance for both fundamental study and applied science. We investigate the hybrid optomechanical cooling with a three-level atomic ensemble fixed in a strong excited optical cavity. By using the…

Quantum Physics · Physics 2017-12-20 Tan Li , Shuo Zhang , He-Liang Huang , Feng-Guang Li , Xiang-Qun Fu , Xiang Wang , Wan-Su Bao

While questions on quantum simulation of ground state physics are mostly focussed on the realization of effective interactions, most work on quantum simulation of thermal physics explores the realization of dynamics towards a thermal mixed…

Advances in controlling and measuring systems of ultra-cold atoms provided strong motivation to theoretical investigations of quantum dynamics in closed many-body systems. Fundamental questions on quantum dynamics and statistical mechanics…

Quantum Gases · Physics 2015-12-04 Ehud Altman

We discuss how the thermalization of an elementary quantum system is modified when the system is placed in an environment out of thermal equilibrium. To this aim we provide a detailed investigation of the dynamics of an atomic system placed…

Quantum Physics · Physics 2013-01-16 Bruno Bellomo , Riccardo Messina , Didier Felbacq , Mauro Antezza

We present approximate analytical method of analysis of stationary states of nonlinear quantum systems with the noise. As an example we consider quantum nonlinear oscillator excited by fluctuating force and found parameter regions with more…

Optics · Physics 2015-01-06 Igor Protsenko , Evgenii Protsenko , Alexander Uskov

Description of nonclassicality of states has hitherto been through violation of Bell inequality and non-separability, with the latter being a stronger constraint. In this paper, we show that this can be further sharpened, by introducing the…

Quantum Physics · Physics 2015-06-18 H. M. Bharath , V. Ravishankar

We study a quantum mechanical toy model that mimics some features of a quenched phase transition. Both by virtue of a time-dependent Hamiltonian or by changing the temperature of the bath we are able to show that even after classicalization…

Quantum Physics · Physics 2009-11-07 Nuno D. Antunes , Fernando C. Lombardo , Diana Monteoliva

We consider the concept of temperature in a setting beyond the standard thermodynamics prescriptions. Namely, rather than restricting to standard coarse-grained measurements, we consider observers able to master any possible quantum…

Quantum Physics · Physics 2012-04-19 Alessandro Ferraro , Artur Garcia-Saez , Antonio Acin

The influence of a Gaussian environment on a quantum system can be described by effectively replacing the continuum with a discrete set of ancillary quantum and classical degrees of freedom. This defines a pseudomode model which can be used…

Quantum Physics · Physics 2024-07-30 Mauro Cirio , Si Luo , Pengfei Liang , Franco Nori , Neill Lambert

Nature is governed by precise physical laws, which can inspire the discovery of new computer-run simulation algorithms. Thermal states are the most ubiquitous for they are the equilibrium states of matter. Simulating thermal states of…

Quantum Physics · Physics 2023-04-13 Oles Shtanko , Ramis Movassagh

The thermodynamic framework of repeated interactions is generalized to an arbitrary open quantum system in contact with a heat bath. Based on these findings the theory is then extended to arbitrary measurements performed on the system. This…

Quantum Physics · Physics 2019-11-04 Philipp Strasberg

Interaction with a thermal environment decoheres the quantum state of a mechanical oscillator. When the interaction is sufficiently strong, such that more than one thermal phonon is introduced within a period of oscillation, quantum…

Quantum Physics · Physics 2018-04-09 Kiran Khosla , George A. Brawley , Michael R. Vanner , Warwick P. Bowen

We prove a general theorem that the action of arbitrary classical noise or random unitary channels can not increase the maximum population of any eigenstate of an open quantum system, assuming initial system-environment factorization. Such…

Quantum Physics · Physics 2016-09-09 Jun Jing , Ravindra W. Chhajlany , Lian-Ao Wu