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Related papers: Lindblad-like quantum tomography for non-Markovian…

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An important open question for the current generation of highly controllable quantum devices is understanding which phases can be realized as stable steady-states under local quantum dynamics. In this work, we show how robust steady-state…

Quantum Physics · Physics 2025-12-02 Sanket Chirame , Abhinav Prem , Sarang Gopalakrishnan , Fiona J. Burnell

A model master equation suitable for quantum computing dynamics is presented. In an ideal quantum computer (QC), a system of qubits evolves in time unitarily and, by virtue of their entanglement, interfere quantum mechanically to solve…

Quantum Physics · Physics 2017-05-31 Frank Tabakin

We consider the dynamics of strongly localized systems subject to dephasing noise with arbitrary correlation time. Although noise inevitably induces delocalization, transport in the noise-induced delocalized phase is subdiffusive in a…

Disordered Systems and Neural Networks · Physics 2017-07-28 Sarang Gopalakrishnan , K. Ranjibul Islam , Michael Knap

The characterization of quantum dynamics is a fundamental and central task in quantum mechanics. This task is typically addressed by quantum process tomography (QPT). Here we present an alternative "direct characterization of quantum…

Quantum Physics · Physics 2007-05-23 M. Mohseni , D. A. Lidar

Quantum state tomography aims to estimate the state of a quantum mechanical system which is described by a trace one, Hermitian positive semidefinite complex matrix, given a set of measurements of the state. Existing works focus on…

Quantum Physics · Physics 2023-03-22 Siva Shanmugam , Sheetal Kalyani

For parameter estimation from an $N$-component composite quantum system, it is known that a separable preparation leads to a mean-squared estimation error scaling as $1/N$ while an entangled preparation can in some conditions afford a…

Quantum Physics · Physics 2019-04-04 Francois Chapeau-Blondeau

In the era of noisy-intermediate-scale quantum computers, we expect to see quantum devices with increasing numbers of qubits emerge in the foreseeable future. To practically run quantum programs, logical qubits have to be mapped to the…

Quantum Physics · Physics 2018-10-22 Will Finigan , Michael Cubeddu , Thomas Lively , Johannes Flick , Prineha Narang

Quantum error mitigation (QEM) is vital for noisy intermediate-scale quantum (NISQ) devices. While most conventional QEM schemes assume discrete gate-based circuits with noise appearing either before or after each gate, the assumptions are…

Quantum Physics · Physics 2021-03-12 Jinzhao Sun , Xiao Yuan , Takahiro Tsunoda , Vlatko Vedral , Simon C. Bejamin , Suguru Endo

Quantum processing units boost entanglement at the level of hardware and enable physical simulations of highly correlated electron states in molecules and intermolecular chemical bonds. The variational quantum eigensolver provides a…

Contemporary quantum computers are inherently noisy, posing significant challenges for the development and testing of quantum software. Simplified or outdated noise assumptions can lead to incorrect assessments of program correctness,…

So far it has been shown that the quantum dynamics cannot be described as a classical Markov process unless the number of classical states is uncountably infinite. In this paper, we present a stochastic model with time-correlated noise that…

Quantum Physics · Physics 2012-04-19 Alberto Montina

Quantum annealing (QA) is one of the efficient methods to calculate the ground-state energy of a problem Hamiltonian. In the absence of noise, QA can accurately estimate the ground-state energy if the adiabatic condition is satisfied.…

Quantum Physics · Physics 2022-10-18 Yuta Shingu , Tetsuro Nikuni , Shiro Kawabata , Yuichiro Matsuzaki

Current quantum computers present significant noise, especially as circuit depth and qubit count increase. Prior work has demonstrated that erroneous outcomes exhibit some behavior in Hamming space, enabling improvements in the output…

Quantum Physics · Physics 2026-04-01 Jake Scally , Austin Myers , Ryan Carmichael , Phat Tran , Xiuwen Liu

We demonstrate that the control protocols of quantum information devices can be simulated by assuming a low-rank ansatz for the density matrix. The rationale underlying this assumption is that quantum information protocols, by design,…

Quantum Physics · Physics 2026-01-27 Leo Goutte , Vincenzo Savona

Characterizing the memory properties of the environment has become critical for the high-fidelity control of qubits and other advanced quantum systems. However, current non-Markovian tomography techniques are either limited to discrete…

Quantum circuits with local particle number conservation (LPNC) restrict the quantum computation to a subspace of the Hilbert space of the qubit register. In a noiseless or fault-tolerant quantum computation, such quantities are preserved.…

Quantum Physics · Physics 2021-04-21 Michael Streif , Martin Leib , Filip Wudarski , Eleanor Rieffel , Zhihui Wang

Stochastic unraveling schemes are powerful computational tools for simulating Lindblad equations, offering significant reductions in memory requirements. However, this advantage is accompanied by increased stochastic uncertainty, and the…

Quantum Physics · Physics 2025-09-25 Yu Cao , Mingfeng He , Xiantao Li

The simulation of many-body open quantum systems is key to solving numerous outstanding problems in physics, chemistry, material science, and in the development of quantum technologies. Near-term quantum computers may bring considerable…

Quantum Physics · Physics 2025-02-05 Sara Santos , Xinyu Song , Vincenzo Savona

Fighting against noise is crucial for NISQ devices to demonstrate practical quantum applications. In this work, we give a new paradigm of quantum error mitigation based on the vectorization of density matrices. Different from the ideas of…

Quantum Physics · Physics 2024-07-22 Zhong-Xia Shang , Zi-Han Chen , Cai-Sheng Cheng

We address the use of a single qubit as a quantum probe to characterize the properties of classical noise. In particular, we focus on the characterization of classical noise arising from the interaction with a stochastic field described by…

Quantum Physics · Physics 2015-10-07 Claudia Benedetti , Matteo G. A. Paris