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Related papers: Maintaining coherence in Quantum Computers

200 papers

A scheme is proposed for protecting quantum states from both independent decoherence and cooperative decoherence. The scheme operates by pairing each qubit (two-state quantum system) with an ancilla qubit and by encoding the states of the…

Quantum Physics · Physics 2009-01-23 Lu-Ming Duan , Guang-Can Guo

Quantum entanglement and coherence are two fundamental resources for quantum information processing. Recent results clearly demonstrate their relevance in quantum technological tasks, including quantum communication and quantum algorithms.…

Quantum Physics · Physics 2018-04-16 Anurag Anshu , Rahul Jain , Alexander Streltsov

We consider decoherence of quantum registers, which consist of the qubits sited approximately periodically in space. The sites of the qubits are permitted to have a small random variance. We derive the explicit conditions under which the…

Quantum Physics · Physics 2007-05-23 Lu-Ming Duan , Guang-Can Guo

To implement quantum information technologies, carefully designed control for preparing a desired state plays a key role. However, in realistic situation, the actual performance of those methodologies is severely limited by decoherence.…

Quantum Physics · Physics 2025-10-02 Kohei Kobayashi

This article presents a comprehensive study of the impact of decoherence on the average correlation for pure quantum states. We explore two primary mechanisms of decoherence: phase damping and amplitude damping, each having distinct effects…

Quantum Physics · Physics 2024-03-19 A. M. Silva

We exploit a novel approximation scheme to obtain a new and compact formula for the parameters underlying coherent-state control of the evolution of a pair of entangled two-level systems. It is appropriate for long times and for relatively…

Quantum Physics · Physics 2010-08-24 Muhammed Yonac , Joseph H. Eberly

There has been no lack of coverage in the past few years in scientific journals of the topic of quantum computation. Rightly so, as this is a novel idea with--so far--at least one very important practical application (prime factorisation)…

Quantum Physics · Physics 2007-05-23 W. L. Fouché , J. Heidema , P. H. Potgieter

Notions of circuit complexity and cost play a key role in quantum computing and simulation where they capture the (weighted) minimal number of gates that is required to implement a unitary. Similar notions also become increasingly prominent…

Quantum Physics · Physics 2021-07-13 J. Eisert

This paper describes the dynamics of a quantum two-level system (qubit) under the influence of an environment modeled by an ensemble of random matrices. In distinction to earlier work, we consider here separable couplings and focus on a…

Quantum Physics · Physics 2015-06-19 M. Carrera , T. Gorin , T. H. Seligman

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

Quantum coherence is a key element in topical research on quantum resource theories and a primary facilitator for design and implementation of quantum technologies. However, the resourcefulness of quantum coherence is severely restricted by…

Quantum Physics · Physics 2015-06-01 Uttam Singh , Manabendra Nath Bera , Himadri Shekhar Dhar , Arun Kumar Pati

Quantum computing promises exponential speed-ups for important simulation and optimization problems. It also poses new CAD problems that are similar to, but more challenging, than the related problems in classical (non-quantum) CAD, such as…

Quantum Physics · Physics 2011-11-04 George F. Viamontes , Igor L. Markov , John P. Hayes

As various quantum computing technologies continue to compete for quantum supremacy, several parameters have emerged as benchmarks for the quality of qubits. These include fidelity, coherence times, connectivity, and a few others. In this…

Quantum Physics · Physics 2020-03-04 Daniel Koch , Avery Torrance , David Kinghorn , Saahil Patel , Laura Wessing , Paul M. Alsing

Quantum computing's potential for exponential speedup is fundamentally limited by decoherence, a phenomenon arising from environmental interactions. Non-Hermitian quantum mechanics, particularly $PT$-symmetric systems, offers a novel…

Quantum Physics · Physics 2025-11-25 Duttatreya , Ipsika Mohanty , Sanjib Dey

Quantum thermodynamics investigates how robust the second law of thermodynamics serves as the unique fundamental law in the small quantum world. To tackle this problem, the quantum coherence constitutes a major difficulty of investigations,…

Quantum Physics · Physics 2025-10-08 Naoto Shiraishi , Ryuji Takagi

The scaling of decoherence rates with the number of q-bits is studied for a simple quantum computer model. Two state q-bits are localised around well-separated positions via trapping potentials, but vibrational motion of q-bits centre of…

Quantum Physics · Physics 2015-06-26 B. J. Dalton

All computing devices, including quantum computers, must exhibit that for a given input, an output is produced in accordance with the program. The outputs generated by quantum computers that fulfill these requirements are not temporally…

Quantum Physics · Physics 2020-04-06 Yutaka Shikano , Kentaro Tamura , Rudy Raymond

There are several important solid-state systems, such as defects in solids, superconducting circuits and molecular qubits, for attractive candidates of quantum computations. Molecular qubits, which benefit from the power of chemistry for…

Quantum Physics · Physics 2017-06-29 Yingqiu Dai , Zhifu Shi , Yue Fu , Xi Qin , Shiwei Mu , Yang Wu , Ji-Hu Su , Lei Qin , Yuan-Qi Zhai , Yi-Fei Deng , Xing Rong , Jiangfeng Du

Clusters of solid-state quantum devices have long-living metastable states of local energy minima which may be used to store quantum information. The low to vanishing rate of dissipation fulfils the prerequisite to maintain quantum…

Quantum Physics · Physics 2013-05-14 Haiqing Wei , Xin Xue , S. D. Morgera

As quantum computers increase in size, the total energy used by a quantum data center, including the cooling, will become a greater concern. The cooling requirements of quantum computers, which must operate at temperatures near absolute…