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Related papers: Tailoring the quantumness of a driven qubit

200 papers

We address the problem of testing the dimensionality of classical and quantum systems in a `black-box' scenario. We develop a general formalism for tackling this problem. This allows us to derive lower bounds on the classical dimension…

Quantum Physics · Physics 2010-12-28 Rodrigo Gallego , Nicolas Brunner , Christopher Hadley , Antonio Acin

We show that the physical mechanism for the equilibration of closed quantum systems is dephasing, and identify the energy scales that determine the equilibration timescale of a given observable. For realistic physical systems (e.g those…

Quantum control of an open system is demonstrated employing a thermodynamically consistent master equation. In this framework, the open system dynamics depend on the control protocol due to the dressing of the system by the drive. This…

Quantum Physics · Physics 2022-09-16 Shimshon Kallush , Roie Dann , Ronnie Kosloff

Non-equilibrium physics is a particularly fascinating field of current research. Generically, driven systems are gradually heated up so that quantum effects die out. In contrast, we show that a driven central spin model including controlled…

Quantum Physics · Physics 2020-03-18 Goetz S. Uhrig

We investigate the effect of dephasing/decoherence on quantum transport through open chaotic ballistic conductors in the semiclassical limit of small Fermi wavelength to system size ratio, $\lambda_F/L << 1$. We use the trajectory-based…

Mesoscale and Nanoscale Physics · Physics 2008-02-17 Robert S. Whitney , Philippe Jacquod , Cyril Petitjean

We study the quantum dissipative Duffing oscillator across a range of system sizes and environmental couplings under varying semiclassical approximations. Using spatial (based on Kullback-Leibler distances between phase-space attractors)…

When a frequency chirped excitation is applied to a classical high-Q nonlinear oscillator, its motion becomes dynamically synchronized to the drive and large oscillation amplitude is observed, provided the drive strength exceeds the…

Quantum Physics · Physics 2013-07-10 K. W. Murch , E. Ginossar , S. J. Weber , R. Vijay , S. M. Girvin , I. Siddiqi

Unitary quantum gates constitute the building blocks of Quantum Computing in the circuit paradigm. In this work, we engineer a locally driven two-qubit Hamiltonian whose instantaneous ground-state dynamics generates the controlled-NOT…

We find the conditions for one quantum system to function as a classical controller of another quantum system: the controller must be an open system and rapidly diagonalised in the basis of the controller variable that is coupled to the…

Quantum Physics · Physics 2015-06-03 G J Milburn

We revisit the problem of switching off unwanted phase evolution and decoherence in a single two-state quantum system in the light of recent results on random dynamical decoupling methods [L. Viola and E. Knill, Phys. Rev. Lett. {\bf 94},…

Quantum Physics · Physics 2009-11-11 Lea F. Santos , Lorenza Viola

We analyze a system of two qubits embedded in two different environments. The qubits are coupled to each other and driven on-resonance by two external classical sources. In the secular limit, we obtain exact analytical results for the…

Quantum Physics · Physics 2010-03-01 J. Li , G. S. Paraoanu

Demonstrating contextual correlations in quantum theory through the violation of a non-contextuality inequality necessarily needs some ``contexts" and thus assumes some compatibility relations between the measurements. As a result, any…

Quantum Physics · Physics 2024-12-03 Gautam Sharma , Chellasamy Jebarathinam , Sk Sazim , Remigiusz Augusiak

We examine whether the chaotic behavior of classical systems with a limited number of degrees of freedom can produce quantum dephasing, against the conventional idea that dephasing takes place only in large systems with a huge number of…

Quantum Physics · Physics 2009-10-30 Hiromichi Nakazato , Mikio Namiki , Saverio Pascazio , Yoshiya Yamanaka

By the example of a kicked quartic oscillator we investigate the dynamics of classically chaotic quantum systems with few degrees of freedom affected by persistent external noise. Stability and reversibility of the motion are analyzed in…

Quantum Physics · Physics 2009-12-27 Valentin V. Sokolov , Oleg V. Zhirov , Yaroslav A. Kharkov

We use a reinforcement learning approach to reduce entropy production in a closed quantum system brought out of equilibrium. Our strategy makes use of an external control Hamiltonian and a policy gradient technique. Our approach bears no…

Quantum Physics · Physics 2024-02-21 Sofia Sgroi , G. Massimo Palma , Mauro Paternostro

We introduce three measures which quantify the degree to which quantum systems possess the robustness exhibited by classical systems when subjected to continuous observation. Using these we show that for a fixed environmental interaction…

Quantum Physics · Physics 2009-11-10 D. J. Atkins , Z. Brady , K. Jacobs , H. M. Wiseman

We consider the problem of energy transport in a chain of coupled dissipative quantum systems in the presence of non-Markovian dephasing. We use a model of non-Markovianity which is experimentally realizable in the context of controlled…

Quantum computers are operated by external driving fields, such as lasers, microwaves or transmission lines, that execute logical operations on multi-qubit registers, leaving the system in a pure state. However, the drive and the logical…

Quantum Physics · Physics 2024-06-21 Sagar Silva Pratapsi , Lorenzo Buffoni , Stefano Gherardini

In the context of quantum information, a quantum battery refers to a system composed of quantum particles that can store and release energy in a way that is governed by the principles of quantum mechanics. The study of open quantum…

Quantum Physics · Physics 2023-04-03 Maryam Hadipour , Soroush Haseli

We investigate the quantum temporal steering (TS), i.e., a temporal analogue of Einstein-Podolsky-Rosen steering, in a dephasing channel which is modeled by a central spin half surrounded by a spin-1/2 \textit{XY} chain where quantum phase…

Quantum Physics · Physics 2018-04-17 Bo Liu , Yixiao Huang , Zhe Sun