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Related papers: On admissible memory kernels for random unitary qu…

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Memoryless time evolutions are ubiquitous in nature but often correspond to a resolution-induced approximation, i.e. there are correlations in time whose effects are undetectable. Recent advances in the dynamical control of small quantum…

We analyze the fidelity of the generalized Pauli channels governed by memory kernel master equations. It is shown that, by appropriate engineering of parameters of the corresponding memory kernel, the quantum evolution with non-local noise…

Quantum Physics · Physics 2019-07-17 Katarzyna Siudzińska , Dariusz Chruściński

We show that measurement can recover the quantum coherence of a qubit in a non-Markovian environment. The experimental demonstration in an optical system is provided by comparing the visibilities (and fidelities) of the final states with…

Quantum Physics · Physics 2009-11-13 JinShi Xu , ChuanFeng Li , Ming Gong , XuBo Zou , Lei Chen , Geng Chen , JianShun Tang , GuangCan Guo

We investigate the dynamical aspects of the quantum switch and find a particular form of quantum memory emerging out of the switch action. We first analyze the loss of information in a general quantum evolution subjected to a quantum switch…

Quantum Physics · Physics 2025-03-26 Vishal Anand , Ananda G. Maity , Subhadip Mitra , Samyadeb Bhattacharya

We study the problem of mapping an unknown mixed quantum state onto a known pure state without the use of unitary transformations. This is achieved with the help of sequential measurements of two non-commuting observables only. We show that…

Quantum Physics · Physics 2009-11-11 L. Roa , M. L. Ladron de Guevara , A. Delgado , A. Klimov

Non-Markovian processes may arise in physics due to memory effects of environmental degrees of freedom. For quantum non-Markovianity, it is an ongoing debate to clarify whether such memory effects have a verifiable quantum origin, or…

Quantum Physics · Physics 2024-04-18 Charlotte Bäcker , Konstantin Beyer , Walter T. Strunz

A quantum learning machine for binary classification of qubit states that does not require quantum memory is introduced and shown to perform with the very same error rate as the optimal (programmable) discrimination machine for any size of…

Quantum Physics · Physics 2012-09-13 G. Sentís , J. Calsamiglia , R. Munoz-Tapia , E. Bagan

We provide a large class of quantum evolution governed by the memory kernel master equation. This class defines quantum analog of so called semi-Markov classical stochastic evolution. In this Letter for the first time we provide a proper…

Quantum Physics · Physics 2017-10-16 Dariusz Chruściński , Andrzej Kossakowski

We propose, formulate and examine novel quantum systems and behavioral phases in which momentary choices of the system's memories interact in order to source the internal interactions and unitary time evolutions of the system. In a closed…

Quantum Physics · Physics 2023-05-17 Alireza Tavanfar , Aliasghar Parvizi , Marco Pezzutto

Non-Markovian features of a system evolution, stemming from memory effects, may be utilized to transfer, storage, and revive basic quantum properties of the system states. It is well known that an atom qubit undergoes non-Markovian dynamics…

Quantum Physics · Physics 2025-11-26 Ali Mortezapour , Mahdi Ahmadi Borji , DaeKil Park , Rosario Lo Franco

Memory (non-Markovian) effect is found to be able to accelerate quantum evolution [S. Deffner and E. Lutz, Phys. Rev. Lett. 111, 010402 (2013)]. In this work, for an atom in a structured reservoir, we show that the mechanism for the speedup…

Quantum Physics · Physics 2015-03-09 Zhen-Yu Xu , Shunlong Luo , W. L. Yang , Chen Liu , Shiqun Zhu

An evolution of a two-level system (qubit) interacting with a single-photon wave packet is analyzed. It is shown that a hierarchy of master equations gives rise to phase covariant qubit evolution. The temporal correlations in the input…

Quantum Physics · Physics 2022-01-05 Anita Dąbrowska , Dariusz Chruściński , Sagnik Chakraborty , Gniewomir Sarbicki

For a quantum system undergoing non-Markovian open quantum dynamics, we demonstrate a tomography algorithm based on multi-time measurements of the system, which reconstructs a minimal environment coupled to the system, such that the system…

Quantum Physics · Physics 2022-08-31 Chu Guo

We give the map representing the evolution of a qubit under the action of non-dissipative random external fields. From this map we construct the corresponding master equation that in turn allows us to phenomenologically introduce population…

Quantum Physics · Physics 2015-06-11 Maria Mannone , Rosario Lo Franco , Giuseppe Compagno

The quantum kernel method, a promising quantum machine learning algorithm, possesses substantial potential for demonstrating quantum advantage. Although the majority of the quantum kernel is constructed in the context of gate-based quantum…

Quantum Physics · Physics 2026-04-15 Hsiang-Wei Huang , Shen-Liang Yang , Chuan-Chi Huang , Yueh-Nan Chen , Hong-Bin Chen

We describe how randomized benchmarking can be used to reconstruct the unital part of any trace-preserving quantum map, which in turn is sufficient for the full characterization of any unitary evolution, or more generally, any unital…

Quantum Physics · Physics 2016-04-12 Shelby Kimmel , Marcus P. da Silva , Colm A. Ryan , Blake R. Johnson , Thomas Ohki

We develop a rigorous formalism for the description of the evolution of observables of quantum systems of particles in the mean-field scaling limit. The corresponding asymptotics of a solution of the initial-value problem of the dual…

Mathematical Physics · Physics 2011-01-24 V. I. Gerasimenko

Machine learning is widely believed to be one of the most promising practical applications of quantum computing. Existing quantum machine learning schemes typically employ a quantum-classical hybrid approach that relies crucially on…

Quantum Physics · Physics 2025-02-11 Qi Ye , Shuangyue Geng , Zizhao Han , Weikang Li , L. -M. Duan , Dong-Ling Deng

Quantum machine learning is a growing research field that aims to perform machine learning tasks assisted by a quantum computer. Kernel-based quantum machine learning models are paradigmatic examples where the kernel involves quantum…

Quantum Physics · Physics 2023-02-06 Diego Tancara , Hossein T. Dinani , Ariel Norambuena , Felipe F. Fanchini , Raúl Coto

Currently, there is no systematic way to describe a quantum process with memory solely in terms of experimentally accessible quantities. However, recent technological advances mean we have control over systems at scales where memory effects…