Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:0801.3723 · Physica E Low-dimensional Systems and Nanostructures

Non-Markovian signatures in the current noise of a charge qubit

Alessandro Braggio, Christian Flindt, Tomáš Novotný

Published Dec 12, 2007• 5 citations
arXivHTMLPDF
DOI
10.1016/j.physe.2007.10.082

Related papers

Decoherence of Josephson charge qubit in non-Markovian environment

Qing-Qian Qiu, Xingfei Zhou, Xian-Ting Liang

Physica B Condensed Matter•Feb 20, 2016•1 citation

Non-Markovian dynamics of a solid-state charge qubit measured by a quantum point contact

Chung-Chin Jian, Po‐Wen Chen, Hsi‐Sheng Goan

Bulletin of the American Physical Society•Feb 28, 2012•0 citations

Non-Markovian dynamics and noise characteristics in continuous measurement of a solid-state charge qubit

JunYan Luo, HuJun Jiao, BiTao Xiong +2 more

We investigate the non-Markovian characteristics in continuous measurement of a charge qubit by a quantum point contact. The backflow of information from the reservoir to the system in the non-Markovian domain gives rise to strikingly different qubit relaxation and dephasing in comparison with the Markovian case. The intriguing non-Markovian dynamics is found to have a direct impact on the output noise feature of the detector. Unambiguously, we observe that the non-Markovian memory effect results in an enhancement of the signal-to-noise ratio, which can even exceed the upper limit of “4,” leading thus to the violation of the Korotkov-Averin bound in quantum measurement. Our study thus may open new possibilities to improve detector's measurement efficiency in a direct and transparent way.

arXiv:1203.2233•Journal of Applied Physics•Nov 4, 2013•8 citations

Current Noise Spectrum of Open Charge Qubits

Ramón Aguado

AIP conference proceedings•Jan 1, 2005•0 citations

Spectral analysis and identification of noises in quantum systems

Re-Bing Wu, Tiefu Li, Abraham G. Kofman +5 more

In quantum information processing, knowledge of the noise in the system is crucial for high-precision manipulation and tomography of coherent quantum operations. Existing strategies for identifying this noise require the use of additional quantum devices or control pulses. We present a noise-identification method directly based on the system's non-Markovian response of an ensemble measurement to the noise. The noise spectrum is identified by reversing the response relationship in the frequency domain. For illustration, the method is applied to superconducting charge qubits, but it is equally applicable to any type of qubits. We find that the identification strategy recovers the well-known Fermi's golden rule under the lowest-order perturbation approximation, which corresponds to the Markovian limit when the measurement time is much longer than the noise correlation time. Beyond such approximation, it is possible to further improve the precision at the so-called optimal point by incorporating the transient response data in the non-Markovian regime. This method is verified with experimental data from coherent oscillations in a superconducting charge qubit.

arXiv:1211.5186•Physical Review A•Feb 19, 2013•22 citations

Charge noise in quantum dot qubits: beyond the Markovian approximation.

Yuan‐Chi Yang, Mark G. Friesen, S. N. Coppersmith

Bulletin of the American Physical Society•Mar 14, 2017•0 citations
We investigate the non-Markovian characteristics in continuous measurement of a charge qubit by a quantum point contact. The backflow of information from the reservoir to the system in the non-Markovian domain gives rise to strikingly different qubit relaxation and dephasing in comparison with the Markovian case. The intriguing non-Markovian dynamics is found to have a direct impact on the output noise feature of the detector. Unambiguously, we observe that the non-Markovian memory effect results in an enhancement of the signal-to-noise ratio, which can even exceed the upper limit of “4,” leading thus to the violation of the Korotkov-Averin bound in quantum measurement. Our study thus may open new possibilities to improve detector's measurement efficiency in a direct and transparent way.
In quantum information processing, knowledge of the noise in the system is crucial for high-precision manipulation and tomography of coherent quantum operations. Existing strategies for identifying this noise require the use of additional quantum devices or control pulses. We present a noise-identification method directly based on the system's non-Markovian response of an ensemble measurement to the noise. The noise spectrum is identified by reversing the response relationship in the frequency domain. For illustration, the method is applied to superconducting charge qubits, but it is equally applicable to any type of qubits. We find that the identification strategy recovers the well-known Fermi's golden rule under the lowest-order perturbation approximation, which corresponds to the Markovian limit when the measurement time is much longer than the noise correlation time. Beyond such approximation, it is possible to further improve the precision at the so-called optimal point by incorporating the transient response data in the non-Markovian regime. This method is verified with experimental data from coherent oscillations in a superconducting charge qubit.