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Related papers: Sudden Decoherence Transitions for Quantum Discord

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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

The scaling of decoherence rates with the number of q-bits is studied for a simple quantum computer model. Two state q-bits are localised around well-separated positions via trapping potentials, but vibrational motion of q-bits centre of…

Quantum Physics · Physics 2015-06-26 B. J. Dalton

Quantum discord, as a measure of all quantum correlations, has been proposed as the key resource in certain quantum communication tasks and quantum computational models without containing much entanglement. Daki\'{c}, Vedral, and Brukner…

Quantum Physics · Physics 2013-02-05 Hai-Rui Wei , Bao-Cang Ren , Fu-Guo Deng

The dynamics of quantum phase transitions poses one of the most challenging problems in modern many-body physics. Here, we study a prototypical example in a clean and well-controlled ultracold atom setup by observing the emergence of…

We present a thorough investigation of the phenomena of frozen and time-invariant quantum discord for two-qubit systems independently interacting with local reservoirs. Our work takes into account several significant effects present in…

Quantum Physics · Physics 2018-03-09 F. T. Tabesh , G. Karpat , S. Maniscalco , S. Salimi , A. S. Khorashad

We explore a strategy for protecting the evolution of a qubit against the effects of environmental noise based on the application of controlled time-dependent perturbations. In the case of a purely decohering coupling, an explicit sequence…

Quantum Physics · Physics 2007-05-23 Lorenza Viola , Seth Lloyd

Quantum correlations between parts of a composite system most clearly reveal themselves through entanglement. Designing, maintaining, and controlling entangled systems is very demanding, which raises the stakes for understanding the…

Quantum Physics · Physics 2019-09-04 Matthew A. Hunt , Igor V. Lerner , Igor V. Yurkevich , Yuval Gefen

We investigate the decoherence of a qubit coupled to either a quantum two-level system (TLS) again coupled to an environment, or a classical fluctuator modeled by random telegraph noise. In order to do this we construct a model for the…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Henry J. Wold , Håkon Brox , Yuri M. Galperin , Joakim Bergli

Quantum correlations between parts of a composite system most clearly reveal themselves through entanglement. Designing, maintaining, and controlling entangled systems is very demanding, which raises the stakes for understanding the…

Quantum Physics · Physics 2019-08-21 Matthew A. Hunt , Igor V. Lerner , Igor V. Yurkevich , Yuval Gefen

We study quantum discord between two free modes of a massive scalar field in a maximally entangled state in de Sitter space. We introduce two observers, one in a global chart and the other in an open chart of de Sitter space, and the…

High Energy Physics - Theory · Physics 2016-12-28 Sugumi Kanno , Jonathan P. Shock , Jiro Soda

Relaxation and decoherence of a qubit coupled to environment and driven by a resonant ac field are investigated by analytically solving Bloch equation of the qubit. It is found that the decoherence of a driven qubit can be decomposed into…

Other Condensed Matter · Physics 2007-05-23 Zhongyuan Zhou , Shih-I Chu , Siyuan Han

Dynamical decoupling protocols are one of the most used tools for efficient quantum error corrections and for reservoir engineering. In this paper we study the effect of dynamical decoupling pulses on the preservation of both quantum and…

Quantum Physics · Physics 2015-12-23 Carole Addis , Göktuğ Karpat , Sabrina Maniscalco

Decoherence of quantum bits arises primarily from the parasitic resistance within the qubit. This study presents the analysis of the decoherence process due to physical interactions between the qubit photons and parasitic resistance atoms,…

Quantum Physics · Physics 2025-10-30 Yoav Koral , Shilo Avraham , Manimuthu Peryasamy , Shmuel E. Schacham , Eliyahu Farber

We study the effects of amplitude and phase damping decoherence in d-dimensional one-way quantum computation (QC). Our investigation shows how information transfer and entangling gate simulations are affected for d>=2. To understand…

Quantum Physics · Physics 2009-11-13 M. S. Tame , M. Paternostro , C. Hadley , S. Bose , M. S. Kim

We investigate how decoherence affects the short-time separation between quantum and classical dynamics for classically chaotic systems, within the framework of a specific model. For a wide range of parameters, the distance between the…

Quantum Physics · Physics 2009-11-10 F. Toscano , R. L. de Matos Filho , L. Davidovich

In this paper, we consider quantum correlations (quantum discord and local quantum uncertainty) in a vertical quantum dot. Their dependencies on magnetic field and temperature are presented in detail. It is noticeable that, quantum discord…

Quantum Physics · Physics 2014-01-21 E. Faizi , H. Eftekhari

We present a multi-level quantum theory of decoherence for a general circuit realization of a superconducting qubit. Using electrical network graph theory, we derive a Hamiltonian for the circuit. The dissipative circuit elements (external…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Guido Burkard , Roger H. Koch , David P. DiVincenzo

Real quantum systems couple to their environment and lose their intrinsic quantum nature through the process known as decoherence. Here we present a method for minimizing decoherence by making it energetically unfavorable. We present a…

Quantum Physics · Physics 2009-11-06 D. Bacon , K. R. Brown , K. B. Whaley

Quantum coherence and quantum correlations are of fundamental and practical significance for the development of quantum mechanics.They are also cornerstones of quantum computation and quantum communication theory. Searching physically…

Quantum Physics · Physics 2018-12-18 Ming-Liang Hu , Xueyuan Hu , Jie-Ci Wang , Yi Peng , Yu-Ran Zhang , Heng Fan

The concept of multiple particle interference is discussed, using insights provided by the classical theory of error correcting codes. This leads to a discussion of error correction in a quantum communication channel or a quantum computer.…

Quantum Physics · Physics 2009-10-30 Andrew Steane