English
Related papers

Related papers: Exactly Solvable BCS-BEC crossover Hamiltonians

200 papers

We study the crossover from the Bardeen-Cooper-Shrieffer (BCS) regime to the Bose-Einstein-condensation (BEC) regime in a quasi-two-dimensional quantum gas of ultracold fermionic atoms. Using an effective two-dimensional Hamiltonian with…

Quantum Gases · Physics 2023-08-16 Jing Zhou , Tingting Shi , Xia-Ji Liu , Hui Hu , Wei Zhang

Using an operator approach based on a commutator scheme that has been previously applied to Richardson's reduced BCS model and the inhomogeneous Dicke model, we obtain general exact solvability requirements for an anisotropic central spin…

Statistical Mechanics · Physics 2018-03-16 Ning Wu

In this talk I present a simple and unified approach to both exact and quasi-exact solvabilities of the one-dimensional Schr\"odinger equation. It is based on the prepotential together with Bethe ansatz equations. This approach gives the…

High Energy Physics - Theory · Physics 2019-12-06 Choon-Lin Ho

We develop a Hamiltonian that describes the time-dependent formation of a molecular Bose-Einstein condensate (BEC) from a Bardeen-Cooper-Schrieffer (BCS) state of fermionic atoms as a result of slowly sweeping through a Feshbach resonance.…

Quantum Gases · Physics 2014-07-01 Bernhard M. Breid , James R. Anglin

We present a unified treatment of exact solutions for a class of four quantum mechanical models, namely the singular anharmonic potential, the generalized quantum isotonic oscillator, the soft-core Coulomb potential, and the…

Mathematical Physics · Physics 2015-06-03 Davids Agboola , Yao-Zhong Zhang

A model describing the Anderson impurity in the Bardeen-Cooper-Schriffer superconductor is proven to exhibit hidden integrability and is diagonalized exactly by the Bethe ansatz.

Superconductivity · Physics 2009-10-30 Valery I. Rupasov

The transient quantum statistical properties of the atoms and molecules in an atom-molecule BEC system are investigated by obtaining a third-order perturbative solution of the Heisenberg's equations of motion corresponding to the…

Quantum Physics · Physics 2014-07-08 Sandip Kumar Giri , Kishore Thapliyal , Biswajit Sen , Anirban Pathak

The superconducting transition in High Temperature Superconductors(HTS) has not been understood. Traditional Bose Einstein Condensation(BEC) theory provides Tc estimates that are many times higher than the experimental values. The proposed…

Superconductivity · Physics 2013-12-05 Vladimir Y. Butko

This work inaugurates a series of complementary studies on Richardson-Gaudin integrable models. We begin by reviewing the foundations of classical and quantum integrability, recalling the algebraic Bethe ansatz solution of the Richardson…

High Energy Physics - Theory · Physics 2025-07-31 Grzegorz Biskowski , Franco Ferrari , Marcin R. Piatek

We analyze the theoretical derivation of the beyond-mean-field equation of state for a two-dimensional gas of dilute, ultracold alkali-metal atoms in the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensate (BEC) crossover. We show…

Quantum Gases · Physics 2018-07-24 G. Bighin , L. Salasnich

Variational method is applied to describe Bose-Einstein condensates (BEC) interacting via a pseudo-potential, taking into account quantum fluctuations around the mean field by the Gaussian approximation. Contributions from the pair-wise…

Condensed Matter · Physics 2007-05-23 Y. Tsue , D. Vautherin , T. Matsui

Though commonly unrecognized, a superconducting BCS condensate consists of equal numbers of two-electron (2e) and two-hole (2h) Cooper pairs (CPs). A complete (in the sense that 2h-CPs are not ignored) boson-fermion statistical model,…

Superconductivity · Physics 2007-05-23 M. de Llano

The exactly solvable BCS Hamiltonian of superconductivity is considered from several viewpoints: Richardson's ansatz, conformal field theory, integrable inhomogenous vertex models and Chern-Simons theory.

High Energy Physics - Theory · Physics 2015-07-27 G. Sierra

We examine key aspects of the theory of the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensation (BEC) crossover, focusing on the temperature dependence of the chemical potential, $\mu$. We identify an accurate method of…

Superconductivity · Physics 2023-10-16 John Sous , Yu He , Steven A. Kivelson

We investigate the crossover from the Bardeen-Cooper-Schrieffer (BCS) state of weakly-bound Cooper pairs to the Bose-Einstein Condensate (BEC) of strongly-bound molecular dimers in a gas of ultracold atoms loaded on a two-dimensional…

Quantum Gases · Physics 2012-08-21 Luca Salasnich , Flavio Toigo

We present the exact Bethe ansatz solution for the two-dimensional BCS pairing Hamiltonian with p_x + i p_y symmetry. Using both mean-field theory and the exact solution we obtain the ground-state phase diagram parameterized by the filling…

Superconductivity · Physics 2011-04-28 Miguel Ibanez , Jon Links , German Sierra , Shao-You Zhao

The creation of a Hamiltonian in the quantum regime which has non-trivial topological features is a central goal of the cold-atom community, enabling widespread exploration of novel phases of quantum matter. A general scheme to synthesize…

Quantum Gases · Physics 2022-04-12 Han Fu , Andreas Glatz , F. Setiawan , Kai-Xuan Yao , Zhendong Zhang , Cheng Chin , K. Levin

We investigate two solvable models for Bose-Einstein condensates and extract physical information by studying the structure of the solutions of their Bethe ansatz equations. A careful observation of these solutions for the ground state of…

Quantum Gases · Physics 2012-04-27 D. Rubeni , A. Foerster , E. Mattei , I. Roditi

The BCS-to-BEC crossover, as well as the nature of Cooper pairs, in a superconducting and Fermi superfluid medium is studied from the exact ground state wavefunction of the reduced BCS Hamiltonian. As the strength of the interaction…

Superconductivity · Physics 2009-11-11 Gerardo Ortiz , Jorge Dukelsky

It is shown that the two-axis countertwisting Hamiltonian is exactly solvable when the quantum number of the total angular momentum of the system is an integer after the Jordan-Schwinger (differential) boson realization of the SU(2)…

Quantum Physics · Physics 2017-02-02 Feng Pan , Yao-Zhong Zhang , Jerry P. Draayer