English
Related papers

Related papers: Entanglement in multi-qubit pure fermionic coheren…

200 papers

We consider fermionic chains where the two halves are either metals with different bandwidths or a metal and an insulator. Both are coupled together by a special bond. We study the ground-state entanglement entropy between the two pieces,…

Statistical Mechanics · Physics 2015-07-09 Viktor Eisler , Ming-Chiang Chung , Ingo Peschel

Entangled multi-qubit states may be generated through a dispersive collective QND measurement of superconducting qubits coupled to a microwave transmission line resonator. Using the quantum trajectory approach, we analyze the stochastic…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Ferdinand Helmer , Florian Marquardt

We study quantum entanglement in one-dimensional correlated fermionic system. Our results show, for the first time, that entanglement can be used to identify quantum phase transitions in fermionic systems.

Quantum Physics · Physics 2009-11-10 Shi-Jian Gu , Shu-Sa Deng , You-Quan Li , Hai-Qing Lin

Mixed states appear naturally in experiment over pure states. So for studying different notions of nonlocality and their relation with entanglement in realistic scenarios, one needs to consider mixed states. In a recent article [Phys. Rev.…

Quantum Physics · Physics 2016-09-14 Biswajit Paul , Kaushiki Mukherjee , Debasis Sarkar

Detecting genuine multipartite entanglement (GME) is a state-characterization task that benchmarks coherence and experimental control in quantum systems. Existing GME tests often require joint measurements on many qubits, posing challenges…

Quantum Physics · Physics 2026-02-18 Nicky Kai Hong Li , Xi Dai , Manuel H. Muñoz-Arias , Kevin Reuer , Marcus Huber , Nicolai Friis

In a periodic lattice system an entangled antipodal pair state, otherwise known as a crosscap state, is a simple two site product state in which spins at antipodal sites are prepared in Bell pairs. Such states have maximal bipartite…

Statistical Mechanics · Physics 2025-12-03 Konstantinos Chalas , Pasquale Calabrese , Colin Rylands

We introduce a framework to identify where the total correlations and entanglement with a chosen degree of freedom reside within the rest of a system, in the context of bosonic many-body Gaussian quantum systems. Our results are organized…

Going beyond the entanglement of microscopic objects (such as photons, spins, and ions), here we propose an efficient approach to produce and control the quantum entanglement of three macroscopic coupled superconducting qubits. By…

Quantum Physics · Physics 2009-11-11 L. F. Wei , Yu-xi Liu , Franco Nori

We introduce the entangled coherent state representation, which provides a powerful technique for efficiently and elegantly describing and analyzing quantum optics sources and detectors while respecting the photon number superselection rule…

Quantum Physics · Physics 2007-05-23 Barry C. Sanders , Stephen D. Bartlett , Terry Rudolph , Peter L. Knight

We provide a complete analysis of mixed three-qubit states composed of a GHZ state and a W state orthogonal to the former. We present optimal decompositions and convex roofs for the three-tangle. Further, we provide an analytical method to…

Quantum Physics · Physics 2007-05-23 Robert Lohmayer , Andreas Osterloh , Jens Siewert , Armin Uhlmann

Optically-controlled exciton dynamics in coupled quantum dots is studied. We show that the maximally entangled Bell states and Greenberger-Horne-Zeilinger (GHZ) states can be robustly generated by manipulating the system parameters to be at…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Ping Zhang , C. K. Chan , Qi-Kun Xue , Xian-Geng Zhao

We describe coherent states and associated generalized Grassmann variables for a system of $m$ independent $q$-boson modes. A resolution of unity in terms of generalized Berezin integrals leads to generalized Grassmann symbolic calculus.…

Mathematical Physics · Physics 2013-01-01 Romina A. Ramirez , Gerardo L. Rossini , Daniel C. Cabra , Enrique F. Moreno

This paper presents properties of the so-called quasi-Bell states: entangled states written as superpositions of nonorthogonal states. It is shown that a special class of those states, namely entangled coherent states, are more robust…

Quantum Physics · Physics 2007-05-23 Osamu Hirota , Steven J. van Enk , Kazuo Nakamura , Masaki Sohma , Kentaro Kato

We investigate some properties of multipartite entanglement of hypergraph states in purely hypergraph theoretical terms. We first introduce an approach for computing the concurrence between two specific qubits of a hypergraph state by using…

Quantum Physics · Physics 2013-05-21 Ri Qu , Juan Wang , Yan-ru Bao , Zong-shang Li , Yi-ping Ma

The ability to entangle quantum systems is crucial for many applications in quantum technology, including quantum communication and quantum computing. Here, we propose a new, simple, and versatile setup for deterministically creating Bell…

Quantum Physics · Physics 2018-12-24 Vincenzo Macrì , Franco Nori , Anton Frisk Kockum

We review some basic elements on k-fermions, which are objects interpolating between bosons and fermions. In particular, we define k-fermionic coherent states and study some of their properties. The decomposition of a Q-uon into a boson and…

Mathematical Physics · Physics 2007-05-23 Mohammed Daoud , Maurice Kibler

We investigate the entanglement in the ground state of systems comprising two and three qubits with random interactions. Since the Hamiltonians also contain deterministic one-body terms, by varying the interaction strength, one can…

Quantum Physics · Physics 2023-07-20 Paulo Freitas Gomes , Marcel Novaes , Fernando Parisio

We discuss how to generate entangled coherent states of four \textrm{microwave} resonators \textrm{(a.k.a. cavities)} coupled by a superconducting qubit. We also show \textrm{that} a GHZ state of four superconducting qubits embedded in four…

Quantum Physics · Physics 2015-05-28 Chui-Ping Yang , Qi-Ping Su , Shi-Biao Zheng , Siyuan Han

In our two preceding papers we studied bipartite composite boson (or quasiboson) systems through their realization in terms of deformed oscillators. Therein, the entanglement characteristics such as the entanglement entropy and purity were…

Quantum Physics · Physics 2015-04-03 A. M. Gavrilik , Yu. A. Mishchenko

We solve a model of a qubit strongly coupled to a massive environmental oscillator mode where the qubit backaction is treated exactly. Using a Ginzburg-Landau formalism, we derive an effective action for this well known localization…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 G. C. Levine , V. N. Muthukumar