English
Related papers

Related papers: Predictability sieve, pointer states, and the clas…

200 papers

The discrimination of quantum states is a central problem in quantum information science and technology. Meanwhile, partial post-selection has emerged as a valuable tool for quantum state engineering. In this work, we bring these two areas…

Quantum Physics · Physics 2026-04-14 Qipeng Qian , Christos N. Gagatsos

Quantum state smoothing is a technique for estimating the quantum state of a partially observed quantum system at time $\tau$, conditioned on an entire observed measurement record (both before and after $\tau$). However, this smoothing…

Quantum Physics · Physics 2020-04-14 Kiarn T. Laverick , Areeya Chantasri , Howard M. Wiseman

In this paper, we give out some effective criterions which can be used to judge the separability of multipartite pure states. We obtain the relationship between separability and Schmidt decomposable of multipartite pure states in Theorem1.…

Quantum Physics · Physics 2007-05-23 Zongwen Yu , Su Hu

Decoherence is the process via which quantum superpositions states are reduced to classical mixtures. Decoherence has been predicted for relativistically accelerated quantum systems, however examples to date have involved restricting the…

Quantum Physics · Physics 2019-01-16 Daiqin Su , Timothy C. Ralph

Description of nonclassicality of states has hitherto been through violation of Bell inequality and non-separability, with the latter being a stronger constraint. In this paper, we show that this can be further sharpened, by introducing the…

Quantum Physics · Physics 2015-06-18 H. M. Bharath , V. Ravishankar

Estimating properties of a quantum state is an indispensable task in various applications of quantum information processing. To predict properties in the post-processing stage, it is inherent to first perceive the quantum state with a…

Quantum Physics · Physics 2024-02-29 Yinfei Li , Sanjib Ghosh , Jiangwei Shang , Qihua Xiong , Xiangdong Zhang

We have studied two complementary decoherence measures purity and fidelity for a generic diffusive noise in two different chaotic systems (the baker and the cat maps). For both quantities, we have found classical structures in quantum…

Quantum Physics · Physics 2015-05-30 Lisandro A. Raviola , Alejandro M. F. Rivas , Gabriel G. Carlo

With a choice of boundary conditions for solutions of the Schr\"odinger equation, state vectors and density operators even for closed systems evolve asymmetrically in time. For open systems, standard quantum mechanics consequently predicts…

Quantum Physics · Physics 2010-05-25 P. W. Bryant

In this paper we present a necessary and sufficient condition of distinguishability of bipartite quantum states. It is shown that the operators to reliably distinguish states need only rounds of projective measurements and classical…

Quantum Physics · Physics 2016-09-08 Ping-Xing Chen , Cheng-Zu Li

Consider a mixed quantum mechanical state, describing a statistical ensemble in terms of an arbitrary density operator $\rho$ of low purity, $\tr\rho^2\ll 1$, and yielding the ensemble averaged expectation value $\tr(\rho A)$ for any…

Statistical Mechanics · Physics 2009-11-13 Peter Reimann

Unique set of coherent states for the anharmonic oscillator is obtained by requiring i. under the quantum mechanical time evolution a coherent state evolves into another, governed by trajectory in the classical phase space (of a related…

Quantum Physics · Physics 2007-05-23 H. S. Sharatchandra

We consider a class of entangled states of a quantum system (S) and a second system (A) where pure states of the former are correlated with mixed states of the latter, and work out the entanglement measure with reference to the nearest…

Quantum Physics · Physics 2008-07-04 Avijit Lahiri , Gautam Ghosh , Sankhasubhra Nag

We formulate the conditions under which the dynamics of a continuously measured quantum system becomes indistinguishable from that of the corresponding classical system. In particular, we demonstrate that even in a classically chaotic…

Quantum Physics · Physics 2009-01-23 Tanmoy Bhattacharya , Salman Habib , Kurt Jacobs

In consistent history quantum theory, a description of the time development of a quantum system requires choosing a framework or consistent family, and then calculating probabilities for the different histories which it contains. It is…

Quantum Physics · Physics 2009-10-30 Robert B. Griffiths

We study the extent to which \psi-epistemic models for quantum measurement statistics---models where the quantum state does not have a real, ontic status---can explain the indistinguishability of nonorthogonal quantum states. This is done…

Quantum Physics · Physics 2014-07-14 Cyril Branciard

The famous Nils Bohr's quantum-classical correspondence principle states that the classical mechanics is a limiting case of the more general quantum mechanics. This implies that ``under certain conditions" quantum laws of motion become…

Quantum Physics · Physics 2013-11-21 Valentin V. Sokolov , Oleg V. Zhirov

A single wave component of a quantum particle can in principle be detected by the way that it interferes with itself, that is, through the local wave function correlation. The interpretation as the expectation of a local translation…

Quantum Physics · Physics 2017-06-07 Alfredo M. Ozorio de Almeida

We demonstrate by an explicit model calculation that the decay of entanglement of two two-state systems (two qubits) is governed by the product of the factors that measure the degree of decoherence of each of the qubits, subject to…

Quantum Physics · Physics 2010-10-12 D. Tolkunov , V. Privman , P. K. Aravind

There is growing belief that the next decade will see the emergence of sensing devices based on the laws of quantum physics that outperform some of our current sensing devices. For example, in frequency estimation, using a probe prepared in…

Quantum Physics · Physics 2016-11-17 Shane Dooley , William J. Munro , Kae Nemoto

Emergence of the classical world from the quantum substrate of our Universe is a long-standing conundrum. I describe three insights into the transition from quantum to classical that are based on the recognition of the role of the…

Quantum Physics · Physics 2018-07-11 Wojciech Hubert Zurek