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Related papers: Quantum thermometry by single-qubit dephasing

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While the ability to measure low temperatures accurately in quantum systems is important in a wide range of experiments, the possibilities and the fundamental limits of quantum thermometry are not yet fully understood theoretically. Here we…

Quantum Physics · Physics 2019-07-10 Patrick P. Potts , Jonatan Bohr Brask , Nicolas Brunner

We present a general and exact formalism for finding the evolution of a quantum system subject to external telegraph noise. The various qubit decoherence rates are determined by the eigenvalues of a transfer matrix. The formalism can be…

Quantum Physics · Physics 2009-11-13 Bin Cheng , Qiang-Hua Wang , Robert Joynt

When quantum information is spread over a system through nonclassical correlation, it makes retrieving information by local measurements difficult---making global measurement necessary for optimal parameter estimation. In this paper, we…

Quantum Physics · Physics 2018-07-13 Akira Sone , Quntao Zhuang , Paola Cappellaro

A reciprocating quantum refrigerator is studied with the purpose of determining the limitations of cooling to absolute zero. We find that if the energy spectrum of the working medium possesses an uncontrollable gap, then there is a minimum…

Quantum Physics · Physics 2009-09-08 Tova Feldmann , Ronnie Kosloff

We develop a general perturbative theory of finite-coupling quantum thermometry up to second order in probe-sample interaction. By assumption, the probe and sample are in thermal equilibrium, so the probe is described by the mean-force…

Most discussions of decoherence in the literature consider the high-temperature regime but it is also known that, in the presence of dissipation, decoherence can occur even at zero temperature. Whereas most previous investigations all…

Quantum Physics · Physics 2009-11-10 G. W. Ford , R. F. O'Connell

We determine quantum precision limits for estimation of damping constants and temperature of lossy bosonic channels. A direct application would be the use of light for estimation of the absorption and the temperature of a transparent slab.…

Quantum Physics · Physics 2020-09-16 Jiaxuan Wang , Luiz Davidovich , Girish Saran Agarwal

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 quantum Cram\'er-Rao theorem states that the quantum Fisher information (QFI) bounds the best achievable precision in the estimation of a quantum parameter $\xi$. This is true, however, under the assumption that the measurement employed…

Quantum Physics · Physics 2018-09-26 Luigi Seveso , Matteo G. A. Paris

We study the ultimate bounds on the estimation of temperature for an interacting quantum system. We consider two coupled bosonic modes that are assumed to be thermal and using quantum estimation theory establish the role the Hamiltonian…

Quantum Physics · Physics 2017-10-04 Steve Campbell , Mohammad Mehboudi , Gabriele De Chiara , Mauro Paternostro

We investigate a system of two coupled qubits interacting with an Ohmic bath as a physical model for the implementation of one logical qubit. In this model, the interaction with the other qubit represents unitary noise while the Ohmic bath…

Quantum Physics · Physics 2025-09-08 G. Di Bello , G. De Filippis , A. Hamma , C. A. Perroni

We propose a configuration of a single three-level quantum emitter embedded in a non-equilibrium steady electromagnetic environment, able to stabilize and control the local temperatures of a target system it interacts with, consisting of a…

Quantum Physics · Physics 2016-01-20 Bruno Leggio , Pierre Doyeux , Riccardo Messina , Mauro Antezza

Estimating correctly the quantum phase of a physical system is a central problem in quantum parameter estimation theory due to its wide range of applications from quantum metrology to cryptography. Ideally, the optimal quantum estimator is…

Quantum Physics · Physics 2021-06-09 Marco A. Rodríguez-García , Isaac Pérez Castillo , P. Barberis-Blostein

We demonstrate that memory in an $N$-qubit system subjected to decoherence, is a potential resource for the slow-down of the entanglement decay. We show that this effect can be used to retain the sub shot-noise sensitivity of the parameter…

Quantum Physics · Physics 2014-12-17 P. Szankowski , M. Trippenbach , J. Chwedenczuk

We propose an ultra-sensitive mass spectrometer based on a coupled quantum-bit-oscillator system. Under dynamical decoupling control of the quantum bit (qubit), the qubit coherence exhibits a comb structure in time domain. The time-comb…

Quantum Physics · Physics 2014-10-29 Nan Zhao , Zhang-qi Yin

The thermalization of an isolated quantum system is described by quantum mechanics and thermodynamics, while these two subjects are still not fully consistent with each other. This leaves a less-explored region where both quantum and…

Quantum Gases · Physics 2024-11-22 Yuqing Wang , Libo Liang , Qinpei Zheng , Qi Huang , Wenlan Chen , Jing Zhang , Xuzong Chen , Jiazhong Hu

We study measures of decoherence and thermalization of a quantum system $S$ in the presence of a quantum environment (bath) $E$. The whole system is prepared in a canonical thermal state at a finite temperature. Applying perturbation theory…

Statistical Mechanics · Physics 2016-03-23 M. A. Novotny , F. Jin , S. Yuan , S. Miyashita , H. De Raedt , K. Michielsen

We introduce the quantitative measures characterizing the rates of decoherence and thermalization of quantum systems. We study the time evolution of these measures in the case of a quantum harmonic oscillator whose relaxation is described…

Quantum Physics · Physics 2009-11-06 V. V. Dodonov , S. S. Mizrahi , A. L. de Souza Silva

One of the central problems in quantum theory is to characterize, detect, and quantify quantumness in terms of classical strategies. Dephasing processes, caused by non-dissipative information exchange between quantum systems and…

Quantum Physics · Physics 2019-08-23 Hong-Bin Chen , Ping-Yuan Lo , Clemens Gneiting , Joonwoo Bae , Yueh-Nan Chen , Franco Nori

The qubit (or a system of two quantum dots) has become a standard paradigm for studying quantum information processes. Our focus is Decoherence due to interaction of the qubit with its environment, leading to noise. We consider quantum…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 Ebad Kamil , Sushanta Dattagupta
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