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Related papers: Keeping a Quantum Bit Alive by Optimized $\pi$-Pul…

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Uhrig's dynamical decoupling pulse sequence has emerged as one universal and highly promising approach to decoherence suppression. So far both the theoretical and experimental studies have examined single-qubit decoherence only. This work…

Quantum Physics · Physics 2015-05-14 Musawwadah Mukhtar , Thuan Beng Saw , Wee Tee Soh , Jiangbin Gong

We experimentally demonstrate the strong suppression of dephasing of a qubit stored in a single \textsuperscript{87}Rb atom in an optical dipole trap by using Carr-Purcell-Meiboom-Gill(CPMG) pulse sequences. Regarded as a repetition of spin…

Quantum Physics · Physics 2013-06-25 Shi Yu , Peng Xu , Xiaodong He , Min Liu , Jin Wang , Mingsheng Zhan

We propose a sequence of pulses intended to preserve the state of a qubit in the presence of strong, coherent coupling to another quantum system. The sequence can be understood as a generalized SWAP and works in formal analogy to the…

Quantum Physics · Physics 2012-09-27 Clemens Müller , Alexander Shnirman , Martin Weides

Numerically we simulate the effect of optimized coherent control pulses with a finite duration on a qubit in a bath of spins. The pulses of finite duration are compared with ideal instantaneous pulses. In particular, we show that properly…

Quantum Physics · Physics 2008-08-26 P. Karbach , S. Pasini , G. S. Uhrig

Nuclear spins are promising candidates for quantum information processing because their good isolation from the environment precludes the rapid loss of quantum coherence. Many strategies have been developed to further extend their…

The coherent control of small quantum system is considered. For a two-level system coupled to an arbitrary bath we consider a pulse of finite duration. We derive the leading and the next-leading order corrections to the evolution operator…

Quantum Physics · Physics 2008-03-11 S. Pasini , T. Fischer , P. Karbach , G. S. Uhrig

We utilize genetic algorithms to find optimal dynamical decoupling (DD) sequences for a single-qubit system subjected to a general decoherence model under a variety of control pulse conditions. We focus on the case of sequences with equal…

Quantum Physics · Physics 2013-11-13 Gregory Quiroz , Daniel A. Lidar

We investigate the nature of the pulse sequence so that unwanted transitions in quantum systems can be inhibited optimally. For this purpose we show that the sequence of pulses proposed by Uhrig [Phys. Rev. Lett. \textbf{98}, 100504 (2007)]…

Quantum Physics · Physics 2015-05-20 C. A. Schroeder , G. S. Agarwal

The proposal for quantum computing with rare-earth-ion qubits in inorganic crystals makes use of the inhomogeneous broadening of optical transitions in the ions to associate individual qubits with ions responding to radiation in selected…

Quantum Physics · Physics 2009-11-10 Ingela Roos , Klaus Molmer

Maintaining quantum coherence is a crucial requirement for quantum computation; hence protecting quantum systems against their irreversible corruption due to environmental noise is an important open problem. Dynamical decoupling (DD) is an…

Quantum Physics · Physics 2011-03-24 Ashok Ajoy , Gonzalo A. Alvarez , Dieter Suter

We report the experimental implementation of dynamical decoupling on a small, non-interacting ensemble of up to 25 optically trapped, neutral Cs atoms. The qubit consists of the two magnetic-insensitive Cs clock states $\left| F=3, m_F=0…

Quantum Physics · Physics 2023-08-04 Sabrina Burgardt , Simon B. Jäger , Julian Feß , Silvia Hiebel , Imke Schneider , Artur Widera

Reducing the circuit depth of quantum circuits is a crucial bottleneck to enabling quantum technology. This depth is inversely proportional to the number of available quantum gates that have been synthesised. Moreover, quantum gate…

Quantum Physics · Physics 2022-12-15 Francesco Preti , Tommaso Calarco , Felix Motzoi

Coherent pulse control for quantum memory is viable in the optical domain but nascent in microwave quantum circuits. We show how to realize coherent storage and on-demand pulse retrieval entirely within a superconducting circuit by…

Quantum Physics · Physics 2015-03-20 Patrick M. Leung , Barry C. Sanders

Avoiding the loss of coherence of quantum mechanical states is an important prerequisite for quantum information processing. Dynamical decoupling (DD) is one of the most effective experimental methods for maintaining coherence, especially…

Quantum Physics · Physics 2010-10-08 Gonzalo A. Alvarez , Ashok Ajoy , Xinhua Peng , Dieter Suter

In order to achieve the high-fidelity quantum control needed for a broad range of quantum information technologies, reducing the effects of noise and system inhomogeneities is an essential task. It is well known that a system can be…

Mesoscale and Nanoscale Physics · Physics 2019-01-30 Junkai Zeng , Xiu-Hao Deng , Antonio Russo , Edwin Barnes

The application of Carr-Purcell-Meiboom-Gill (CPMG) $\pi-$trains for dynamically decoupling a system from its environment has been extensively studied in a variety of physical systems. When applied to dipolar solids, recent experiments have…

Other Condensed Matter · Physics 2015-06-18 Clark D. Ridge , Lauren F. O'Donnell , Jamie D. Walls

There are two distinct techniques of proven effectiveness for extending the coherence lifetime of spin qubits in environments of other spins. One is dynamical decoupling, whereby the qubit is subjected to a carefully timed sequence of…

Quantum Physics · Physics 2015-06-16 Setrak J. Balian , Ren-Bao Liu , T. S. Monteiro

We propose a new pulse sequence for dynamical averaging of the dipole-dipole interactions and inhomogeneities of the magnetic fields in the nuclear spin system. The sequence contains a short cycle of the periodic resonant pulse excitation…

Quantum Physics · Physics 2015-03-05 S. A. Moiseev , V. A. Skrebnev

We investigate the effectiveness of different dynamical decoupling protocols for storage of a single qubit in the presence of a purely dephasing bosonic bath, with emphasis on comparing quantum coherence preservation under uniform vs.…

Quantum Physics · Physics 2015-05-14 Thomas E. Hodgson , Lorenza Viola , Irene D'Amico

Constructing high-fidelity control fields that are robust to control, system, and/or surrounding environment uncertainties is a crucial objective for quantum information processing. Using the two-state Landau-Zener model for illustrative…

Quantum Physics · Physics 2012-05-23 Matthew D. Grace , Jason Dominy , Wayne M. Witzel , Malcolm S. Carroll