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Quantum computers are inherently affected by noise. While in the long-term error correction codes will account for noise at the cost of increasing physical qubits, in the near-term the performance of any quantum algorithm should be tested…

We address the dynamics of entanglement and quantum discord for two non interacting qubits initially prepared in a maximally entangled state and then subjected to a classical colored noise, i.e. coupled with an external environment…

Quantum Physics · Physics 2013-06-06 C. Benedetti , F. Buscemi , P. Bordone , M. G. A. Paris

Composite quantum systems exhibit non-local correlations. These counter intuitive correlations form a resource for quantum information processing and quantum computation. In our previous work on two qubit maximally entangled mixed states,…

Quantum Physics · Physics 2015-10-02 K. G. Paulson , S. V. M. Satyanarayana

In this article we review properties of Gaussian states and describe operations on them. The interaction of the electromagnetic field with an absorbing dielectric as a special type of environmental interaction will serve as the basis for…

Quantum Physics · Physics 2007-05-23 Stefan Scheel , Dirk-Gunnar Welsch

We study decoherence in a qubit with the distance between the two levels affected by random flips of bistable fluctuators. For the case of a single fluctuator we evaluate explicitly an exact expression for the phase-memory decay in the echo…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Y. M. Galperin , B. L. Altshuler , J. Bergli , D. V. Shantsev

The unavoidable effect of the environmental noise due to nuclear spins and charge traps is included in the study of the hybrid qubit dynamics. Hybrid qubit dues its name to the advantageous combination of manipulation speed of a charge…

Quantum Physics · Physics 2019-11-14 E. Ferraro , M. Fanciulli , M. De Michielis

Grover's quantum algorithm improves any classical search algorithm. We show how random Gaussian noise at each step of the algorithm can be modelled easily because of the exact recursion formulas available for computing the quantum amplitude…

Quantum Physics · Physics 2009-10-31 B. Pablo-Norman , M. Ruiz-Altaba

Quantum gates executed on physical hardware are inevitably degraded by environmental noise. While state purification effectively distills static quantum resources, the dynamic execution of quantum algorithms requires a higher-order approach…

Quantum Physics · Physics 2026-04-02 Jiayi Zhao , Yu-Ao Chen , Guocheng Zhen , Chengkai Zhu , Ranyiliu Chen , Xin Wang

Decoherence-free states protect quantum information from collective noise, the predominant cause of decoherence in current implementations of quantum communication and computation. Here we demonstrate that spontaneous parametric…

Despite being one of the hallmarks of quantum physics, there is a lack of operational interpretations of quantum coherence. Here we provide an operational interpretation of coherence of a quantum system, in terms of the amount of noise that…

Quantum Physics · Physics 2017-04-10 Uttam Singh , Manabendra Nath Bera , Avijit Misra , Arun Kumar Pati

The hyperfine interaction with nuclear spins (or, Overhauser noise) has long been viewed as a leading source of decoherence in individual quantum dot spin qubits. Here we show that in a coupled multi-qubit system consisting of as few as…

Mesoscale and Nanoscale Physics · Physics 2016-02-23 Edwin Barnes , Dong-Ling Deng , Robert E. Throckmorton , Yang-Le Wu , S. Das Sarma

The dynamics of quantum systems are unavoidably influenced by their environment and in turn observing a quantum system (probe) can allow one to measure its environment: Measurements and controlled manipulation of the probe such as dynamical…

Quantum Physics · Physics 2019-07-16 Matthias M. Müller , Stefano Gherardini , Filippo Caruso

Gaussian quantum systems exhibit many explicitly quantum effects but can be simulated classically. Using both the Hilbert space (Koopman) and the phase-space (Moyal) formalisms we investigate how robust this classicality is. We find…

Quantum Physics · Physics 2017-02-23 Aida Ahmadzadegan , Robert B. Mann , Daniel R. Terno

The ability to preserve multipartite entanglement in noisy environments is central to advancing quantum information processing. In this work, we develop a semiclassical theoretical model of three entangled qubits exposed to local Markov…

Quantum Physics · Physics 2025-11-14 Stephen Brockerhoff , Brittany Corn-Agostini

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

Two-level systems (TLS) are the major source of dephasing of spin qubits in numerous quantum computing platforms. In spite of much effort, it has been difficult to substantially mitigate the effects of this noise or, in many cases, to fully…

Quantum Physics · Physics 2025-07-25 Yujun Choi , S. N. Coppersmith , Robert Joynt

We present a study of the prospects for coherence preservation in solid-state spin qubits using dynamical decoupling protocols. Recent experiments have provided the first demonstrations of multipulse dynamical decoupling sequences in this…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 M. J. Biercuk , H. Bluhm

The most common error models for quantum computers assume the independence of errors on different qubits. However, most noise mechanisms have some correlations in space. We show how to improve quantum information processing for few-qubit…

Quantum Physics · Physics 2018-12-19 Vickram N. Premakumar , Robert Joynt

The relations between the resource theoretic measures of quantum coherence are rigorously investigated for various Markovian and non-Markovian channels for the two-qubit $X$ states with specific attention to the maximum and minimum…

Quantum Physics · Physics 2022-06-07 Sandeep Mishra , Kishore Thapliyal , Anirban Pathak

In this paper, we describe a tensor network simulation of a neutral atom quantum system under the presence of noise, while introducing a new purity-preserving truncation technique that compromises between the simplicity of the matrix…

Quantum Physics · Physics 2025-06-03 James Allen , Matthew Otten , Stephen Gray , Bryan K. Clark