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Related papers: Phase Fluctuations and Pseudogap Phenomena

200 papers

We investigate single-particle properties of a mass-imbalanced Fermi gas in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover region. In the presence of mass imbalance, we point out that the ordinary $T$-matrix…

Quantum Gases · Physics 2013-11-20 Ryo Hanai , Takashi Kashimura , Ryota Watanabe , Daisuke Inotani , Yoji Ohashi

We investigate pseudo-gap phenomena realized in the BCS pairing model with a long but finite interaction range. We calculate the single-particle self-energy in all order exactly in the temperature range where the superconducting fluctuation…

Superconductivity · Physics 2009-11-07 Satoshi Fujimoto

We investigate single-particle excitations and strong-coupling effects in a two-dimensional Fermi gas. Including pairing fluctuations within a Gaussian fluctuation theory, we calculate the density of states $\rho(\omega)$ near the…

Quantum Gases · Physics 2015-06-22 M. Matsumoto , Y. Ohashi

We address the important question of how to characterize the normal state of fermionic superfluids under the influence of a strong effective magnetic field, implemented through rapid rotation or novel artificial field techniques. We…

Quantum Gases · Physics 2013-10-25 Peter Scherpelz , Dan Wulin , K. Levin , A. K. Rajagopal

We investigate strong pairing fluctuations and effects of a harmonic trap in the superfluid phase of an ultracold Fermi gas. Including amplitude and phase fluctuations of the inhomogeneous superfluid order parameter $\Delta(r)$ in a trap…

Quantum Gases · Physics 2015-06-11 Ryota Watanabe , Shunji Tsuchiya , Yoji Ohashi

We investigate the pseudogap onset temperature $T^*$, the superconducting transition temperature $T_c$ and the general nature of the pseudogap phase using a diagrammatic BCS-Bose Einstein crossover theory. This decoupling scheme is based on…

Superconductivity · Physics 2007-05-23 Jiri Maly , Boldizsar Janko , K. Levin

We investigate pseudogap phenomena in a two-dimensional Fermi gas. Including pairing fluctuations within a self-consistent $T$-matrix approximation, we determine the pseudogap temperature $T^*$ below which a dip appears in the density of…

Quantum Gases · Physics 2018-01-17 Morio Matsumoto , Ryo Hanai , Daisuke Inotani , Yoji Ohashi

We outline a microscopic approach to the superconducting fluctuations and pairing correlations in the attractive Hubbard model above Tc, using the functional integral method. A crossover from BCS superconductivity to Bose condensation of…

Superconductivity · Physics 2007-05-23 R. Micnas

We study mesoscopic disorder fluctuations in an anisotropic gap superconductor, which lead to the spatial variations of the local pairing temperature and formation of superconducting islands above the mean-field transition. We derive the…

Superconductivity · Physics 2009-11-13 Victor Galitski

The physics of the pseudo-gap phase of high temperature cuprate superconductors has been an enduring mystery in the past thirty years. The ubiquitous presence of the pseudo-gap phase in under-doped cuprates suggests that its understanding…

Superconductivity · Physics 2020-03-26 C. Pépin , D. Chakraborty , M. Grandadam , S. Sarkar

It is well known that conventional pairing fluctuation theory at the Hartree level leads to a normal state pseudogap in the fermionic spectrum. Our goal is to extend this Hartree approximated scheme to arrive at a generalized mean field…

Superconductivity · Physics 2007-05-23 Jelena Stajic , Andrew Iyengar , Qijin Chen , K. Levin

On the basis of the observed short coherence lengths in the cuprates we argue that a BCS-Bose-Einstein condensation (BEC) crossover approach is an appropriate starting point for correcting the mean field approach of BCS and, thereby, for…

Superconductivity · Physics 2007-05-23 K. Levin , Qijin Chen , Ioan Kosztin

Ultracold atomic Fermi gases present an opportunity to study strongly interacting Fermi systems in a controlled and uncomplicated setting. The ability to tune attractive interactions has led to the discovery of superfluidity in these…

Quantum Gases · Physics 2010-07-29 J. P. Gaebler , J. T. Stewart , T. E. Drake , D. S. Jin , A. Perali , P. Pieri , G. C. Strinati

We present a self-consistent approach to deal with the pairing-fluctuation effects in quasi-two-dimensional superconducting systems. Besides the Cooper pairs in the Bose-Einstein condensate, there are pairs occupying the excited states,…

Superconductivity · Physics 2009-11-07 Xin-Zhong Yan

Pseudogap phenomena and the formation of Fermi arcs in underdoped cuprates are numerically studied in the presence of phase fluctuations that are simulated by an XY model. Most importantly the spectral function for each Monte Carlo sample…

Superconductivity · Physics 2011-07-22 Qiang Han , Tao Li , Z. D. Wang

We examine the role of the anisotropy of superconducting critical thermal fluctuations in the opening of a pseudogap in a quasi-two dimensional superconductor such as a cuprate-oxide high-temperature superconductor. When the anisotropy…

Superconductivity · Physics 2009-11-11 Fusayoshi J. Ohkawa

We consider a quantum-critical metal with interaction mediated by fluctuations of a critical order parameter. This interaction gives rise to two competing tendencies -- pairing and non-Fermi liquid behavior. Due to competition, the pairing…

Superconductivity · Physics 2019-06-05 Artem Abanov , Yi-Ming Wu , Yuxuan Wang , Andrey V. Chubukov

We investigate pseudogap phenomena in the unitarity limit of a trapped superfluid Fermi gas. Including effect of strong pairing fluctuations within a $T$-matrix approximation, as well as effects of a harmonic trap within the local density…

Quantum Gases · Physics 2015-05-28 Ryota Watanabe , Shunji Tsuchiya , Yoji Ohashi

In this paper we study the effects of the strong coupling superconductivity on the normal state electronic structure. We point out that the pseudogap phenomena in High-T_c cuprates are naturally explained as a precursor of the strong…

Superconductivity · Physics 2009-10-31 Youichi Yanase , Kosaku Yamada

We investigate strong-coupling effects on normal state properties of an ultracold Fermi gas. Within the framework of $T$-matrix approximation in terms of pairing fluctuations, we calculate the single-particle density of states (DOS), as…

Quantum Gases · Physics 2013-05-29 Shunji Tsuchiya , Ryota Watanabe , Yoji Ohashi