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Related papers: Using Parity Kicks for Decoherence Control

200 papers

Decoupling is an important tool to prolong the coherence time of quantum systems. Most decoupling schemes have been assuming selective controls on the system and it is believed that with global pulses one can only decouple systems with…

Quantum Physics · Physics 2015-06-24 Haidong Yuan , Van D. M. Koroleva , Navin Khaneja

It is shown that the magnetic state decoherence produced by collisions in a thermal vapor can be suppressed by the application of a train of ultrafast optical pulses.

Atomic Physics · Physics 2009-11-06 C. Search , P. R. Berman

Identifying and controlling decoherence in single electron sources (SES) is important for their applications in quantum information processing. The recent experiments with ultrashort electron pulses [J. D. Fletcher et al., Nat. Commun. 10,…

Mesoscale and Nanoscale Physics · Physics 2024-04-18 Sungguen Ryu , Rosa López , Llorenç Serra , David Sanchez , Michael Moskalets

We demonstrate perfect coherence preservation in an atom interferometer perturbed by kicks from off-resonant standing wave pulses. Under most conditions, the decoherence induced by the pulses reduces the signal; however, the coherence is…

Atomic Physics · Physics 2014-09-09 A. Tonyushkin , S. Wu , M. Prentiss

We propose a strategy to suppress decoherence of a solid-state qubit coupled to non-Markovian noises by attaching the qubit to a chaotic setup with the broad power distribution in particular in the high-frequency domain. Different from the…

Quantum Physics · Physics 2012-04-09 Jing Zhang , Yu-xi Liu , Wei-Min Zhang , Lian-Ao Wu , Re-Bing Wu , Tzyh-Jong Tarn

In the framework of nuclear magnetic resonance, we consider the general problem of the coherent control of a spin coupled to a bath by means of composite or continuous pulses of duration $\tau_\mathrm{p}$. We show explicity that it is…

Quantum Physics · Physics 2010-03-16 S. Pasini , P. Karbach , C. Raas , G. S. Uhrig

The dynamics of a decohering two-level system driven by a suitable control Hamiltonian is studied. The control procedure is implemented as a sequence of radiofrequency pulses that repetitively flip the state of the system, a technique that…

Quantum Physics · Physics 2009-10-31 Lorenza Viola , Seth Lloyd

Relaxation effects impose fundamental limitations on our ability to coherently control quantum mechanical phenomena. In this letter, we establish physical limits on how closely can a quantum mechanical system be steered to a desired target…

Quantum Physics · Physics 2009-11-10 N. Khaneja , B. Luy , S. J. Glaser

Due to omnipresent environmental interferences, quantum coherences inevitably undergo irreversible transformations over certain time-scales, thus leading to the loss of encoded information. This process, known as decoherence, has been a…

Quantum Physics · Physics 2014-06-19 Swathi S. Hegde , T. S. Mahesh

The decoherence in trapped ion induced by coupling the ion to the engineered reservoir is studied in this paper. The engineered reservoir is simulated by random variations in the trap frequency, and the trapped ion is treated as a two-level…

Quantum Physics · Physics 2009-11-06 X. X. Yi , D. L. Zhou , C. P. Sun

We consider a quantum harmonic oscillator coupled to a general nonequilibrium environment. We show that the decoherence factor can be expressed in terms of a measurable effective temperature, defined via a generalized…

Quantum Physics · Physics 2010-11-25 Joseph Beer , Eric Lutz

Dynamical decoupling pulse sequences have been used to extend coherence times in quantum systems ever since the discovery of the spin-echo effect. Here we introduce a method of recursively concatenated dynamical decoupling pulses, designed…

Quantum Physics · Physics 2007-05-23 K. Khodjasteh , D. A. Lidar

Decoherence may significantly affect the polarization state of optical pulses propagating in dispersive media because of the unavoidable presence of more than a single frequency in the envelope of the pulse. Here we report on the…

We consider the effect of broadband decoherence on the performance of refocusing sequences, having in mind applications of dynamical decoupling in concatenation with quantum error correcting codes as the first stage of coherence protection.…

Quantum Physics · Physics 2015-05-13 Leonid P. Pryadko , Gregory Quiroz

The aim of dynamical decoupling consists in the suppression of decoherence by appropriate coherent control of a quantum register. Effectively, the interaction with the environment is reduced. In particular, a sequence of $\pi$ pulses is…

Quantum Physics · Physics 2008-08-18 Götz S. Uhrig

Thermal decoherence is a major obstacle to the realization of quantum coherence for massive mechanical oscillators. Although optical trapping has been used to reduce the thermal decoherence rate for such oscillators, it also increases the…

Quantum Physics · Physics 2016-09-21 Nobuyuki Matsumoto , Kentaro Komori , Sosuke Ito , Yuta Michimura , Yoichi Aso

We study the state decay of two qubits interacted with a common harmonic oscillator reservoir. There are both decoherence error and the error caused by the amplitude change of the superradiant state. We show that frequent $\pi$-phase pulses…

Quantum Physics · Physics 2015-05-20 Jia-Zhong Hu , Xiang-Bin Wang , LC Kwek

We employ a continuous dynamical decoupling scheme to suppress the decoherence induced by elastic collisions of cold atoms. Using a continuous echo pulse we achieve a thirty-fold increase in the coherence time of Rb87 atoms trapped in a…

Quantum Physics · Physics 2009-05-28 Yoav Sagi , Ido Almog , Nir Davidson

One of the biggest challenges for implementing quantum devices is the requirement to perform accurate quantum gates. The destructive effects of interactions with the environment present some of the most difficult obstacles that must be…

Quantum Physics · Physics 2012-11-06 Alexandre M. Souza , Gonzalo A. Álvarez , Dieter Suter

The control of thermal decoherence via dynamical decoupling and via the quantum Zeno effect (Zeno control) is investigated for a model of trapped ion, where the dynamics of two low lying hyperfine states undergoes decoherence due to the…

Quantum Physics · Physics 2010-01-31 S. Tasaki , A. Tokuse , P. Facchi , S. Pascazio