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Related papers: Decoherence of a Driven Qubit

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Characterizing and understanding the environment affecting quantum systems is critical to elucidate its physical properties and engineer better quantum devices. We develop an approach to reduce the quantum environment causing single-qubit…

Quantum Physics · Physics 2022-10-19 Won Kyu Calvin Sun , Paola Cappellaro

Decoherence largely limits the physical realization of qubits and its mitigation is critical to quantum science. Here, we construct a robust qubit embedded in a decoherence-protected subspace, obtained by hybridizing an applied microwave…

We examine the dependence of decoherence on the spectral density of the environment as well as on the initial state of the system. We use two simple examples to illustrate some important effects. The simplest derivation of the general form…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Juan Pablo Paz

In this paper we study the decoherence and purity of a driven solid-state qubit in the Ohmic bath by using the method based on the master equation. At first, instead of solving the master equation we investigate the coefficients of the…

Quantum Physics · Physics 2009-11-13 Zhi-Qiang Li , Xian-Ting Liang

The efficiency of the future devices for quantum information processing will be limited mostly by the finite decoherence rates of the individual qubits and quantum gates. Recently, substantial progress was achieved in enhancing the time…

Mesoscale and Nanoscale Physics · Physics 2014-04-10 E. Paladino , Y. M. Galperin , G. Falci , B. L. Altshuler

The dynamical properties of a quantum system can be profoundly influenced by its environment. Usually, the environment provokes decoherence and its action on the system can often be schematized by adding a noise term in the Hamiltonian.…

Quantum Physics · Physics 2015-06-26 S. Pascazio

The manipulation fidelity of a single electron qubit gate-confined in a $^{28}$Si/SiGe quantum dot has recently been drastically improved by nuclear isotope purification. Here, we identify the dominant source for low-frequency qubit…

In this study, we examine decoherence of qubits system coupled independently by using influence functional. We especially concentrated on the effect of qubit flip process. We examine the zero-dimensional qubit and one-dimensional qubits…

Quantum Physics · Physics 2008-09-30 Toshifumi Itakura

We present a quantum open-system approach to analyze the nonunitary dynamics of a superconducting qubit when it evolves under the influence of external noise. We consider the presence of longitudinal and transverse environmental…

Quantum Physics · Physics 2015-06-18 Fernando C. Lombardo , Paula I. Villar

Electron spin qubits are a promising platform for quantum computation. Environmental noise impedes coherent operations by limiting the qubit relaxation ($T_1$) and dephasing ($T_{\phi}$) times. There are multiple sources of such noise,…

Quantum Physics · Physics 2022-09-27 Yujun Choi , Robert Joynt

W generalize the scheme for detection of qubit-environment entanglement to qudit-environment systems. This is of relevance for many-qubit systems and the quantification of the operation of quantum algorithms under the influence of external…

Quantum Physics · Physics 2025-04-01 Małgorzata Strzałka , Katarzyna Roszak

A qubit (containing two quantum states, 1 and 2), is coupled to a control register (state 3), which is subject to telegraph noise. We study the time evolution of the density matrix $\rho$ of an electron which starts in some coherent state…

Mesoscale and Nanoscale Physics · Physics 2009-09-01 Amnon Aharony , Ora Entin-Wohlman , Sushanta Dattagupta

The dynamical evolution of a quantum register of arbitrary length coupled to an environment of arbitrary coherence length is predicted within a relevant model of decoherence. The results are reported for quantum bits (qubits) coupling…

Quantum Physics · Physics 2009-11-07 John H. Reina , Luis Quiroga , Neil F. Johnson

We study the decoherence effect of charge noise on a single flip-flop qubit and two dipole-coupled qubits. We find that a single flip-flop qubit is highly resistant to charge noise at its sweet spots. However, due to the proximity of the…

Quantum Physics · Physics 2021-04-16 John Truong , Xuedong Hu

The decay of spin-valley states is studied in a suspended carbon nanotube double quantum dot via leakage current in Pauli blockade and via dephasing and decoherence of a qubit. From the magnetic field dependence of the leakage current,…

Mesoscale and Nanoscale Physics · Physics 2017-05-02 T. Pei , A. Pályi , M. Mergenthaler , N. Ares , A. Mavalankar , J. H. Warner , G. A. D. Briggs , E. A. Laird

Quantum computing promises significant speed-up for certain types of computational problems. However, robust implementations of semiconducting qubits must overcome the effects of charge noise that currently limit coherence during gate…

Quantum Physics · Physics 2017-07-12 Mark Friesen , Joydip Ghosh , M. A. Eriksson , S. N. Coppersmith

The elimination of decoherence of a multiphoton two-state quantum system by using an appropriate external driving field is considered. The multiphoton process caused by the noise field has a supersymmetric Lie algebraic structure. The…

Quantum Physics · Physics 2007-05-23 Jian-Qi Shen , Zhi-Chao Ruan , Sailing He

The prospect of developing magnetic qubits is discussed. The first part of the article makes suggestions on how to achieve the coherent quantum superposition of spin states in small ferromagnetic clusters, weakly uncompensated…

Statistical Mechanics · Physics 2007-05-23 Eugene M. Chudnovsky

We investigate the phonon-induced decoherence and dissipation in a donor-based charge quantum bit realized by the orbital states of an electron shared by two dopant ions which are implanted in a silicon host crystal. The dopant ions are…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 J. Eckel , S. Weiss , M. Thorwart

We investigate the steering dissipative dynamics of a two-level system (qubit) by means of the modulation of an assisted tunneling degree of freedom which is described by a quantum-oscillator spin-boson model. Our results reveal that the…

Quantum Physics · Physics 2022-04-07 Zhiguo Lü , Hang Zheng