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For an open quantum system to evolve under CPTP maps, assumptions are made on the initial correlations between the system and the environment. Hermitian-preserving trace-preserving (HPTP) maps are considered as the local dynamic maps beyond…

Quantum Physics · Physics 2023-08-04 Ningping Cao , Maxwell Fitzsimmons , Zachary Mann , Rajesh Pereira , Raymond Laflamme

The advantages of quantum information processing are in many cases obtained as consequences of quantum interactions, especially for computational tasks where two-qubit interactions are essential. In this work, we establish the framework of…

Quantum Physics · Physics 2019-09-11 Sudipto Singha Roy , Joonwoo Bae

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

Divisibility of dynamical maps is a central notion in the study of quantum non-Markovianity, providing a natural framework to characterize memory effects via time-local master equations. In this work, we generalize the notion of…

The description of the dynamics of an open quantum system in the presence of initial correlations with the environment needs different mathematical tools than the standard approach to reduced dynamics, which is based on the use of a…

Quantum Physics · Physics 2022-11-11 Andrea Smirne , Nina Megier , Bassano Vacchini

We make a thorough study of the spreading of quantum coherence (QC), as quantified by the $l_{1}$-norm QC, when a qubit (a two-level quantum system) is subjected to noise quantum channels commonly appearing in quantum information science.…

Quantum Physics · Physics 2017-02-10 Mauro B. Pozzobom , Jonas Maziero

The problem of defining quantum non-Markovianity has proven elusive, with various in-equivalent criteria put forth to address it. The concept of CP-indivisibility and the hierarchy of stronger divisibility criteria going up to…

Quantum Physics · Physics 2020-09-15 Shrikant Utagi , R. Srikanth , Subhashish Banerjee

Maps that are not completely positive (CP) are often useful to describe the dynamics of open systems. An apparent violation of complete positivity can occur because there are prior correlations of the principal system with the environment,…

Quantum Physics · Physics 2008-04-21 Hilary Carteret , Daniel R. Terno , Karol Zyczkowski

The evolution of a composite closed system using the integral wave equation with the kernel in the form of path integral is considered. It is supposed that a quantum particle is a subsystem of this system. The evolution of the reduced…

Quantum Physics · Physics 2017-08-30 A. Yu. Samarin

Convex combinations of the completely positive (CP) as well as CP-divisible, continuous time dynamical maps arising from collision models are investigated. While the individual maps are both CP and Markovian we find that convex combinations…

Quantum Physics · Physics 2020-03-18 Vijay Pathak , Anil Shaji

The quantum evolution can be accelerated in non-Markovian environment. Previous results showed that the formation of system-environment bound state governs the quantum speedup. Although a stronger bound state in the system-environment…

Quantum Physics · Physics 2018-02-27 Jing Wang , Yunan Wu , Ziyang Xie

We analyze the connections between the non-Markovianity degree of the most general phase-damping qubit maps and their legitimate mixtures. Using the results for image non-increasing dynamical maps, we formulate the necessary and sufficient…

Quantum Physics · Physics 2022-05-25 Katarzyna Siudzińska

In open quantum systems, it is known that if the system and environment are in a product state, the evolution of the system is given by a linear completely positive (CP) Hermitian map. CP maps are a subset of general linear Hermitian maps,…

Quantum Physics · Physics 2025-06-25 Daniel Dilley , Alvin Gonzales , Mark Byrd

By use of the two measures presented recently, the indivisibility and the backflow of information, we study the non-Markovianity of the dynamics for a two-level system interacting with a zero-temperature structured environment without using…

Quantum Physics · Physics 2015-06-05 Hao-Sheng Zeng , Ning Tang , Yan-Ping Zheng , Tian-Tian Xu

Researchers have proposed formal definitions of quantitative information flow based on information theoretic notions such as the Shannon entropy, the min entropy, the guessing entropy, and channel capacity. This paper investigates the…

Cryptography and Security · Computer Science 2010-04-02 Hirotoshi Yasuoka , Tachio Terauchi

We revise the 'no-signaling' condition for the supraluminal communication between two spatially separated finite quantum systems of arbitrary dimensions, thus generalizing a similar preceding approach for two-qubits: non-linear evolution…

Quantum Physics · Physics 2007-05-23 M. Ferrero , D. Salgado , J. L. Sanchez-Gomez

It is known that the time evolution of a subsystem from an initial state to two later times, t1, t2 (t2 > t1), are both completely positive (CP) but it is shown here that in the intermediate times between t1 and t2, in general, it need not…

Quantum Physics · Physics 2011-04-26 A. R. Usha Devi , A. K. Rajagopal , Sudha

Non-P-divisibility is the strongest divisibility-based notion of quantum non-Markovianity. The generalized trace distance (GTD) based criterion is known to be an optimal witness of non-P-divisibility of dynamical maps, in the sense that a…

Quantum Physics · Physics 2026-05-26 Vijay Pathak , R. Srikanth

In this study, we investigate qubit dynamics under PT and Anti-PT-symmetric non-Hermitian Hamiltonians, focusing on phase evolution, decoherence, quantum speed limits (QSL), and R\'enyi entanglement entropies. Using similarity…

Quantum Physics · Physics 2025-08-11 Amir Ahmadi , Roozbeh H. Asgari , Javad T. Firouzjaee

We revisit recent results on integrable cases for higher-dimensional generalizations of the 2D pentagram map: short-diagonal, dented, deep-dented, and corrugated versions, and define a universal class of pentagram maps, which are proved to…

Dynamical Systems · Mathematics 2015-06-19 Boris Khesin , Fedor Soloviev