English
Related papers

Related papers: Universality in Phase Transitions for Ultracold Fe…

200 papers

We review recent developments in the field of ultracold atomic Fermi gases. As the cold atom system evolves from BCS to Bose-Einstein condensation (BEC), the behavior of the thermodynamics, and the particle density profiles evolves smoothly…

Superconductivity · Physics 2011-09-13 K. Levin , Qijin Chen

In a system of ultracold atoms near a Feshbach resonance, pairs of atoms can be associated into universal dimers by an oscillating magnetic field with frequency near that determined by the dimer binding energy. We present a simple…

Quantum Gases · Physics 2015-03-18 Christian Langmack , D. Hudson Smith , Eric Braaten

By using a Path Integral formalism, we study the fluctuating fields in the order parameter for a 3D uniform Fermi gas at T<Tc. The BCS-BEC crossover condition is included into the analysis in the framework of the usual s-wave scattering…

Strongly Correlated Electrons · Physics 2011-07-01 H. Vivas

Feshbach scattering resonances are being utilized in atomic gases to explore the entire crossover region from a Bose-Einstein Condensation (BEC) of composite bosons to a Bardeen-Cooper-Schrieffer (BCS) of Cooper pairs. Several theoretical…

Superconductivity · Physics 2009-11-10 S. De Palo , M. L. Chiofalo , M. J. Holland , S. J. J. M. F. Kokkelmans

We determine the effects of quantum fluctuations about the T=0 mean field solution of the BCS-BEC crossover in a dilute Fermi gas using the functional integral method. These fluctuations are described in terms of the zero point motion of…

Other Condensed Matter · Physics 2008-03-20 Roberto B. Diener , Rajdeep Sensarma , Mohit Randeria

A universal characterization of interactions in few- and many-body quantum systems is often possible without detailed description of the interaction potential, and has become a defacto assumption for cold atom research. Universality in this…

Other Condensed Matter · Physics 2017-08-23 Nathan Gemelke , Chen-Lung Hung , Xibo Zhang , Cheng Chin

We investigate the Bose-Einstein condensation (BEC, superfluidity) of particle-hole pairs in ultracold Fermionic atoms with repulsive interactionsand arbitrary polarization, which are trapped within optical lattices. Near a Feshbach…

Atomic Physics · Physics 2007-05-23 Chaohong Lee

We analyze the phase diagram of superfluidity for two-species fermion mixtures from the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensation (BEC) limit as a function of scattering parameter, population imbalance and mass…

Superconductivity · Physics 2009-11-13 M. Iskin , C. A. R. Sa de Melo

In this paper we construct an effective field theory for a condensate of cold Fermi atoms whose scattering is controlled by a narrow Feshbach resonance. We show how, from first principles, it permits a hydrodynamic description of the…

Superconductivity · Physics 2012-01-18 Chi-Yong Lin , Da-Shin Lee , Ray J. Rivers

We study thermodynamics of a two-species Feshbach-resonant atomic Fermi gas in a periodic potential, focusing in a deep optical potential where a tight binding model is applicable. We show that for more than half-filled band the gas…

Quantum Gases · Physics 2013-01-08 Zhaochuan Shen , L. Radzihovsky , V. Gurarie

We discuss an integrable model of interacting Fermions in one dimension, that allows an exact description of the crossover from a BCS- to a Bose-like superfluid. This model bridges the Gaudin-Yang model of attractive spin 1/2 Fermions to…

Statistical Mechanics · Physics 2007-05-23 J. N. Fuchs , A. Recati , W. Zwerger

We investigate evolution of the quantum coherence in the ultracold mixture of fermionic atoms and bosonic dimer molecules. Interactions are there experimentally controlled via tuning the external magnetic field. Consequently, the fermionic…

Superconductivity · Physics 2015-06-25 T. Domanski

Advances in atomic physics have led to the possibility of a coherent transformation between ultra-cold atoms and molecules including between completely bosonic condensates. Such transformations are enabled by the magneto-association of…

Quantum Gases · Physics 2024-12-11 Vijay Ganesh Sadhasivam , Fumika Suzuki , Bin Yan , Nikolai A. Sinitsyn

In a trapped atomic Fermi gas, one can tune continuously via a Feshbach resonance the effective pairing interaction between fermionic atoms from very weak to very strong. As a consequence, the low temperature superfluidity evolves…

Quantum Gases · Physics 2011-01-17 Yi Yu , Qijin Chen

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

We investigate the effective interaction between Cooper-pair molecules in the st rong-coupling BEC regime of a superfluid Fermi gas with a Feshbach resonance. Our work uses a path integral formulation and a renormalization group (RG) analy…

Superconductivity · Physics 2009-11-11 Y. Ohashi

We present some general considerations on the properties of a two-component ultra-cold Fermi gas along the BEC-BCS crossover. It is shown that the interaction energy and the ground state energy can be written in terms of a single…

Strongly Correlated Electrons · Physics 2009-11-13 Shizhong Zhang , Anthony J. Leggett

We show how to describe the $T \neq 0$ behavior associated with the usual BCS- Bose Einstein condensation (BEC) crossover ground state. We confine our attention here to the BEC and near-BEC regime where analytical calculations are possible.…

Soft Condensed Matter · Physics 2011-09-13 Jelena Stajic , Qijin Chen , K. Levin

Understanding and controlling interactions of ultracold molecules is a cornerstone of quantum chemistry. While the laboratory creation of degenerate molecular gases comprised of bosonic atoms has unlocked powerful new platforms for quantum…

Quantum Gases · Physics 2025-12-30 Zhiqiang Wang , Ke Wang , Zhendong Zhang , Qijin Chen , Cheng Chin , K. Levin

We present an exact many-body theory of ultracold fermionic gases for the Bose-Einstein condensation (BEC) regime of the BEC-BCS crossover. This is a purely fermionic approach which treats explicitely and systematically the dimers formed in…

Statistical Mechanics · Physics 2010-07-23 R. Combescot , X. Leyronas