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Related papers: Limits on Preserving Quantum Coherence using Multi…

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Unwanted interaction between a quantum system and its fluctuating environment leads to decoherence and is the primary obstacle to establishing a scalable quantum information processing architecture. Strategies such as environmental and…

The control of quantum dynamics via specially tailored laser pulses is a long-standing goal in physics and chemistry. Partly, this dream has come true, as sophisticated pulse shaping experiments allow to coherently control product ratios of…

Quantum Physics · Physics 2007-07-16 J. Werschnik , E. K. U. Gross

Measurements in quantum mechanics cannot perfectly distinguish all states and necessarily disturb the measured system. We present and analyse a proposal to demonstrate fundamental limits on quantum control of a single qubit arising from…

One approach to maintaining phase coherence of qubits through dynamical decoupling consists of applying a sequence of Hahn spin-echo pulses. Recent studies have shown that, in certain noise environments, judicious choice of the delay times…

Quantum Physics · Physics 2009-06-24 Hermann Uys , Michael J. Biercuk , John J. Bollinger

We present a numerically-optimized multipulse framework for the quantum control of a single-electron charge qubit. Our framework defines a set of pulse sequences, necessary for the manipulation of the ideal qubit basis, that avoids errors…

Quantum Physics · Physics 2023-03-10 Aleksander Lasek , Hugo V. Lepage , Kexin Zhang , Thierry Ferrus , Crispin H. W. Barnes

Starting with the basic control system model often employed in NMR pulse design, we derive more realistic control system models taking into account effects such as off-resonant excitation for systems with fixed inter-qubit coupling…

Quantum Physics · Physics 2009-10-01 Sonia Schirmer

Reliable processing of quantum information for developing quantum technologies requires precise control of out-of-equilibrium many-bodysystems. This is a highly challenging task as the fragility of quantum states to external perturbations…

Quantum instruments derived from composite systems allow greater measurement precision than their classical counterparts due to coherences maintained between N components; spins, atoms or photons. Decoherence that plagues real-world devices…

Quantum Physics · Physics 2014-02-04 Sergey I. Knysh , Edward H. Chen , Gabriel A. Durkin

We show that if an efficient classical representation of the dynamics exists, optimal control problems on many-body quantum systems can be solved efficiently with finite precision. We show that the size of the space of parameters necessary…

Quantum Physics · Physics 2014-07-09 S. Lloyd , S. Montangero

We investigate the optimal dynamical decoupling sequence for a qubit coupled to an ohmic environment. By analytically computing the derivatives of the decoherence function, the optimal pulse locations are found to satisfy a set of nonlinear…

Quantum Physics · Physics 2010-09-21 Yu Pan , Zairong Xi , Wei Cui

Current quantum computers suffer from noise that stems from interactions between the quantum system that constitutes the quantum device and its environment. These interactions can be suppressed through dynamical decoupling to reduce…

Quantum Physics · Physics 2024-12-06 Arefur Rahman , Daniel J. Egger , Christian Arenz

Dynamical decoupling is an important tool to counter decoherence and dissipation effects in quantum systems originating from environmental interactions. It has been used successfully in many experiments; however, there is still a gap…

Quantum Physics · Physics 2014-06-25 J. Z. Bernád , H. Frydrych

Quantum control is an essential tool for the operation of quantum technologies such as quantum computers, simulators, and sensors. Although there are sophisticated theoretical tools for developing quantum control protocols, formulating…

Quantum Physics · Physics 2013-04-02 Hanhan Li , Alireza Shabani , Mohan Sarovar , Birgitta K. Whaley

The last decade has witnessed remarkable progress in the development of quantum technologies. Although fault-tolerant devices likely remain years away, the noisy intermediate-scale quantum devices of today may be leveraged for other…

We introduce a novel control method for robust quantum information processing suited for quantum integrated photonics. We utilize off-resonant detunings as control parameters to derive a new family of composite pulses for high-fidelity…

Quantum Physics · Physics 2019-10-02 Elica Kyoseva , Hadar Greener , Haim Suchowski

We show that the addition of correlated phases to the recently developed method of randomized dynamical decoupling pulse sequences [Physical Review Letters 122, 200403 (2019)] can improve its performance in quantum sensing. In particular,…

Quantum Physics · Physics 2020-05-07 Zhen-Yu Wang , Jorge Casanova , Martin B. Plenio

Optimal control theory provides recipes to achieve quantum operations with high fidelity and speed, as required in quantum technologies such as quantum sensing and computation. While technical advances have achieved the ultrastrong driving…

Quantum Physics · Physics 2015-11-25 M. Hirose , P. Cappellaro

We present a remarkable finding that a recently discovered [G. S. Uhrig, Phys. Rev. Lett. 98, 100504 (2007)] series of pulse sequences, designed to optimally restore coherence to a qubit in the spin-boson model of decoherence, is in fact…

Quantum Physics · Physics 2009-11-13 B. Lee , W. M. Witzel , S. Das Sarma

Aperiodic dynamical decoupling (DD) sequences of $\pi$ pulses are of great interest to decoherence control and have been recently extended from single-qubit to two-qubit systems. If the environmental noise power spectrum is made available,…

Quantum Physics · Physics 2011-10-25 Yu Pan , Zai-Rong Xi , Jiangbin Gong

Control of quantum systems is a central element of high-precision experiments and the development of quantum technological applications. Control pulses that are typically temporally or spatially modulated are often designed based on…

Quantum Physics · Physics 2021-01-04 Frederic Sauvage , Florian Mintert