English
Related papers

Related papers: Remarks on pairwise comparisons, transition amplit…

200 papers

The composite particle duality extends the notions of both flux attachment and statistical transmutation in spacetime dimensions beyond 2+1D. It constitutes an exact correspondence that can be understood either as a theoretical framework or…

Strongly Correlated Electrons · Physics 2024-10-29 Gerard Valentí-Rojas , Joel Priestley , Patrik Öhberg

Quantum systems with a finite number of states at all times have been a primary element of many physical models in nuclear and elementary particle physics, as well as in condensed matter physics. Today, however, due to a practical demand in…

Quantum Physics · Physics 2021-08-31 Arsen Khvedelidze , Dimitar Mladenov , Astghik Torosyan

Quantum phase transitions (QPTs), including symmetry breaking and topological types, always associated with gap closing and opening. We analyze the topological features of the quantum phase boundary of the XY model in a transverse magnetic…

Strongly Correlated Electrons · Physics 2019-04-17 X. M. Yang , G. Zhang , Z. Song

Motivated by studies of typical properties of quantum states in statistical mechanics, we introduce phase-random states, an ensemble of pure states with fixed amplitudes and uniformly distributed phases in a fixed basis. We first show that…

Quantum Physics · Physics 2015-03-19 Yoshifumi Nakata , Peter S. Turner , Mio Murao

We present the full characterization of phase-randomized or phase-averaged coherent states, a class of states exploited in communication channels and in decoy state-based quantum key distribution protocols. In particular, we report on the…

Quantum Physics · Physics 2013-09-16 Alessia Allevi , Maria Bondani , Paulina Marian , Tudor A. Marian , Stefano Olivares

The geometric phase for a pure quantal state undergoing an arbitrary evolution is a ``memory'' of the geometry of the path in the projective Hilbert space of the system. We find that Uhlmann's geometric phase for a mixed quantal state…

Quantum Physics · Physics 2016-08-16 Marie Ericsson , Arun K. Pati , Erik Sjöqvist , Johan Brännlund , Daniel. K. L. Oi

We define an operational notion of phases in interferometry for a quantum system undergoing a completely positive non-unitary evolution. This definition is based on the concepts of quantum measurement theory. The suitable generalization of…

Quantum Physics · Physics 2009-11-07 J. G. Peixoto de Faria , A. F. R. de Toledo Piza , M. C. Nemes

Measurement incompatibility stipulates the existence of quantum measurements that cannot be carried out simultaneously on single systems. We show that the set of input-output probabilities obtained from d-dimensional classical systems…

Quantum Physics · Physics 2023-06-13 Debashis Saha , Debarshi Das , Arun Kumar Das , Bihalan Bhattacharya , A. S. Majumdar

Everett's concept of relative state is used to introduce a geometric phase that depends nontrivially on entanglement in a pure quantum state. We show that this phase can be measured in multiparticle interferometry. A correlation-dependent…

Quantum Physics · Physics 2015-05-13 Erik Sjöqvist

The quantum phase transitions provide a paradigm for studying collective quantum phenomena that are a result of competing non-commuting interactions. This paper will study the ground state properties and quantum critical dynamics of the…

Quantum Physics · Physics 2026-01-27 Rudraksh Sharma

It is quite common to use the generalized probabilistic theories (GPTs) as generic models to reconstruct quantum theory from a few basic principles and to gain a better understanding of the probabilistic or information theoretic foundations…

Quantum Physics · Physics 2026-03-12 Gerd Niestegge

We quantify the emergent complexity of quantum states near quantum critical points on regular 1D lattices, via complex network measures based on quantum mutual information as the adjacency matrix, in direct analogy to quantifying the…

Statistical Mechanics · Physics 2017-12-06 Marc Andrew Valdez , Daniel Jaschke , David L. Vargas , Lincoln D. Carr

Starting from a simple estimation problem, here we propose a general approach for decoding quantum measurements from the perspective of information extraction. By virtue of the estimation fidelity only, we provide surprisingly simple…

Quantum Physics · Physics 2022-10-04 Huangjun Zhu

In a quantum measurement, a coupling $g$ between the system S and the apparatus A triggers the establishment of correlations, which provide statistical information about S. Robust registration requires A to be macroscopic, and a dynamical…

Quantum Physics · Physics 2015-06-26 Armen E. Allahverdyan , Roger Balian , Theo M. Nieuwenhuizen

We examine the complementarity among coherence (visibility), predictability, and entanglement for qubit and qutrit systems subjected to noisy quantum channels. Using the system-path entanglement framework, analytical expressions for all…

Quantum Physics · Physics 2025-12-01 Pratidhwani Swain , Ramita Sarkar , Sukanta K. Tripathy , Prasanta K. Panigrahi

Off-diagonal mixed state phases based upon a concept of orthogonality adapted to unitary evolution and a proper normalisation condition are introduced. Some particular instances are analysed and parallel transport leading to the…

Quantum Physics · Physics 2016-08-16 Erik Sjöqvist , Stefan Filipp

We derive and experimentally investigate a strong uncertainty relation valid for any $n$ unitary operators, which implies the standard uncertainty relation as a special case, and which can be written in terms of geometric phases. It is…

Mutually unbiased bases determine an optimal set of measurements to extract complete information about the quantum state of a system. However, quite often a priori information about the state exist, making some of the measurement bases…

Quantum Physics · Physics 2015-06-12 A. B. Klimov , G. Bjork , L. L. Sanchez-Soto

We derive necessary and sufficient inseparability conditions imposed on the variance matrix of symmetric qubits. These constraints are identified by examining a structural parallelism between continuous variable states and two qubit states.…

Quantum Physics · Physics 2007-05-23 A. R. Usha Devi , M. S. Uma , R. Prabhu , A. K. Rajagopal

It is commonly stated that decoherence in open quantum systems is due to growing entanglement with an environment. In practice, however, surprisingly often decoherence may equally well be described by random unitary dynamics without…

Quantum Physics · Physics 2009-10-29 Julius Helm , Walter T. Strunz