English
Related papers

Related papers: Non-Markovian dephasing and depolarizing channels

200 papers

We introduce a measure of non-Markovianity based on the minimal amount of extra Markovian noise we have to add to the process via incoherent mixing, in order to make the resulting transformation Markovian too at all times. We show how to…

Quantum Physics · Physics 2021-01-27 Dario De Santis , Vittorio Giovannetti

We introduce map-dependent quantum characteristic functions constructed from the normalized Choi operator of quantum dynamical maps. We prove a Bochner--Choi positivity theorem establishing that the positive-type condition of the associated…

Quantum Physics · Physics 2026-04-21 Koichi Nakagawa

We investigate the problem of reversing quantum dynamics, specifically via optimal Petz recovery maps. We focus on typical decoherence channels, such as dephasing, depolarizing and amplitude damping. We illustrate how well a physically…

Quantum Physics · Physics 2022-05-06 Lea Lautenbacher , Fernando de Melo , Nadja K. Bernardes

We study quantum processes, as one parameter families of differentiable completely positive and trace preserving (CPTP) maps. Using different representations of the generator, and the Sylvester criterion for positive semi-definite matrices,…

Quantum Physics · Physics 2019-09-17 Gustavo Montes Cabrera , David Davalos , Thomas Gorin

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

Divisibility of dynamical maps is visualized by trajectories in the parameter space and analyzed within the framework of collision models. We introduce ultimate completely positive (CP) divisible processes, which lose CP divisibility under…

Quantum Physics · Physics 2017-09-20 S. N. Filippov , J. Piilo , S. Maniscalco , M. Ziman

We investigate the distributed dense coding (DC) protocol, involving multiple senders and a single or two receivers under the influence of non-Markovian noise, acting on the encoded qubits transmitted from senders to the receiver(s). We…

Quantum Physics · Physics 2024-03-26 Abhishek Muhuri , Rivu Gupta , Srijon Ghosh , Aditi Sen De

We introduce a non-Markovianity measure for continuous variable open quantum systems based on the idea put forward in H.-P. Breuer et al., Phys. Rev. Lett.\textbf{103}, 210401 (2009), i.e., by quantifying the flow of information from the…

Non-Markovian noise, arising from the memory effect in the environment, poses substantial challenges to conventional quantum noise suppression protocols, including quantum error correction and mitigation. We introduce a channel…

Quantum Physics · Physics 2024-12-17 Zhenhuan Liu , Yunlong Xiao , Zhenyu Cai

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

We analyze the relation between CP-divisibility and the lack of information backflow for an arbitrary -- not necessarily invertible -- dynamical map. It is well known that CP-divisibility always implies lack of information backflow.…

Quantum Physics · Physics 2018-08-29 Dariusz Chruściński , Ángel Rivas , Erling Størmer

In this paper we present a detailed critical study of several recently proposed non-Markovianity measures. We analyse their properties for single qubit and two-qubit systems in both pure-dephasing and dissipative scenarios. More…

Quantum Physics · Physics 2016-09-20 C. Addis , B. Bylicka , D. Chruściński , S. Maniscalco

We investigate dynamics of Gaussian states of continuous variable systems under Gaussianity preserving channels. We introduce a hierarchy of such evolutions encompassing Markovian, weakly and strongly non-Markovian processes, and provide…

We characterize a class of Markovian dynamics using the concept of divisible dynamical map. Moreover we provide a family of criteria which can distinguish Markovian and non-Markovian dynamics. These Markovianity criteria are based on a…

Quantum Physics · Physics 2012-09-03 Dariusz Chruściński , Andrzej Kossakowski

We unveil a novel source of non-Markovianity for the dynamics of quantum systems, which appears when the system does not explore the full set of dynamical trajectories in the interaction with its environment. We term this effect…

We introduce a method of characterization of non-Markovianity using coherence of a system interacting with the environment. We show that under the allowed incoherent operations, monotonicity of a valid coherence measure is affected due to…

Quantum Physics · Physics 2016-11-28 Titas Chanda , Samyadeb Bhattacharya

The way a principle system and its environment interact characterizes the non-Markovianity of the dynamics. Herein, we investigate the non-Markovian dynamics of photon polarization in a birefringent crystal. We consider the so-called…

Quantum Physics · Physics 2018-10-31 Kai-Hung Wang , Shih-Hsuan Chen , Yu-Cheng Lin , Che-Ming Li

We propose an all-optical experiment to quantify non-Markovianity in an open quantum system through quantum coherence of a single quantum bit. We use an amplitude damping channel implemented by an optical setup with an intense laser beam…

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

Non-Markovian effects in open quantum system dynamics usually manifest backflow of information from the environment to the system, indicating complete-positive divisibility breaking of the dynamics. We provide a criterion for witnessing…

Quantum Physics · Physics 2024-03-04 Bivas Mallick , Saheli Mukherjee , Ananda G. Maity , A. S. Majumdar