Related papers: Long-range photon fluctuations enhance photon-medi…
Motivated by recent experiments reporting superconductivity only at very low temperature in a class of heavy fermion compounds, we study the impact of energy fluctuations with small momentum transfer on the pairing instability near an…
When the electron-phonon coupling is quadratic in the phonon coordinates, electrons can pair to form bipolarons due to phonon zero-point fluctuations, a purely quantum effect. We study superconductivity originating from this pairing…
We study a mechanism to induce superconductivity in atomically thin semiconductors where excitons mediate an effective attraction between electrons. Our model includes interaction effects beyond the paradigm of phonon-mediated…
We consider the behaviour of the fluctuating specific heat and conductivity in the vicinity of the upper critical field line for a two-band superconductor. Multiple-band effects are pronounced when the bands have very different coherence…
In 2D electronic spectroscopy studies, long-lived quantum beats have recently been observed in photosynthetic systems, and it has been suggested that the beats are produced by quantum mechanically mixed electronic and vibrational states.…
There is currently great interest in the strong coupling between the quantized photon field of a cavity and electronic or other degrees of freedom in materials. A major goal is the creation of novel collective states entangling photons with…
Polaritons, formed as a result of strong hybridization of matter with light, are promising for important applications including organic solar cells, optical logic gates, and qubits. Owing to large binding energies of Frenkel excitons…
We investigate the superfluid phase transition in a gas of Fermi atoms loaded on a three-dimensional optical lattice. When the lattice potential is strong, this system can be well described by an attractive Hubbard model. In this model, we…
Ultracold Fermi atoms allow the realization of the crossover from Bardeen-Cooper-Schrieffer (BCS) superconductivity to Bose- Einstein condensation (BEC), by varying with continuity the attraction between fermions of different species. In…
We theoretically examine photoassociation of a two-component Fermi degenerate gas. Our focus is on adjusting the atom-atom interaction, and thereby increasing the critical temperature of the BCS transition to the superfluid state. In order…
The influence of strong internal forces on photon-assisted scattering and on the displacement mechanism of magnetoconductivity oscillations in a two-dimensional (2D) electron gas is theoretically studied. The theory is applied to the highly…
Very efficient amplification of light-matter waves (polaritons), that are a superposition of cavity photons and excitons [1] has recently been reported[2-11]. The optical gain curve versus the pump power shows a threshold and then saturates…
Bose-Fermi systems such as mixtures of electrons with excitons or exciton-polaritons are extensively discussed as candidates to host a variety of intriguing phenomena, including polaron formation, drag effects, supersolidity, and…
We report on a fully self-consistent determination of a phase transition to a superconducting state in a conserving approximation. The transition temperature calculated for a two-dimensional Hubbard model with an attractive interaction in…
We solve the problem of fermionic pairing mediated by a massless boson in the limit of large coupling constant. At weak coupling, the transition temperature is exponentially small and superconductivity is robust against phase fluctuation.…
The drag effects in the system of spatially separated electrons and excitons in coupled quantum wells (CQWs) embedded in an optical microcavity are predicted. It is shown that at low temperature an electron current induces the polariton…
The effective attractive interaction between electrons, mediated by electron-phonon coupling, is a well-established mechanism of conventional superconductivity. In metals exhibiting a Fermi surface, the critical temperature of…
Phase transitions and their associated crossovers are imprinted in the behavior of fluctuations. Motivated by recent experiments on ultracold atoms in optical lattices, we compute the thermodynamic density fluctuations $\delta N^2$ of the…
We examine possibility of enhancement of superconductive critical temperature in two-dimensions. The weak coupling BCS theory is applied, especially when the Fermi level is near the edges of the electronic bands. The attractive interaction…
Coupling between electrons and phonons (lattice vibrations) drives the formation of the electron pairs responsible for conventional superconductivity. The lack of direct evidence for electron-phonon coupling in the electron dynamics of the…