相关论文: Asymptotically Exact Solution for Superconductivit…
We study the effects of quantum fluctuations on the transport properties of multiband superconductors near a pair-breaking quantum critical point. For this purpose, we consider a minimal model of the quantum phase transition in a system…
In the two-component Fermi gas with a contact interaction, a pseudogap regime can exist at temperatures between the superfluid critical temperature $T_c$ and a temperature $T^* > T_c$. This regime is characterized by pairing correlations…
Symmetry-breaking phases in many-fermion systems are characterized by anomalous functions that represent transient processes during which some properties of free particles, such as spin or charge, are not conserved. Connecting the…
We present a theory that is a non-Fermi-liquid counterpart of the Abrikosov-Gor'kov pair-breaking theory due to paramagnetic impurities in superconductors. To this end we analyze a model of interacting electrons and phonons that is a…
We present a functional-based approach to compute thermal expectation values for actions expressed in the $G-\Sigma$ formalism, applicable to any time sequence ordering. Utilizing this framework, we analyze the linear response to an…
We study the $\pm J$ three-dimensional Ising model with a spatially uniaxially anisotropic bond randomness on the simple cubic lattice. The $\pm J$ random exchange is applied in the $xy$ planes, whereas in the z direction only a…
It is known that in the two-dimensional disordered superconductors electron-electron interactions in the Cooper channel lead to the negative logarithmic in temperature correction to the tunneling conductance above the critical temperature.…
The weak-coupling limits of the gap and critical temperature computed within Eliashberg theory surprisingly deviate from the BCS theory predictions by a factor of $1/\sqrt{e}$. Interestingly, however, the ratio of these two quantities…
We study the normal state and the superconducting transition in the Attractive Hubbard Model in three dimensions, using self-consistent diagrammatics. Our results for the self-consistent $T$-matrix approximation are consistent with 3D-XY…
Transient responses of the electronic excitation and coherent soft phonon are investigated both above and below the ferroelectric phase transition temperature T$_{c}$ in Pb$_{1-x}$Ge$_{x}$Te by using an optical pump-probe technique. The…
This paper treats a number of issues of the cuprates, ranging from the spin resonance peak and the linear one-particle scattering rate to the superconducting transition, in the frame of a Fermi liquid model. Recent ARPES expts. by Valla et…
Very high applied pressure induces superconductivity with the transition temperature ($T_c$) exceeding 19 K in elemental yttrium, but relatively little is known about the nature of that superconductivity. From point-contact spectroscopy…
Using the fluctuation-exchange (FLEX) approximation we study an effective five-band Hubbard model for iron-pnictide superconductors obtained from the first-principles band structure. We preclude deformations of the Fermi surface due to…
A systematic comparison is conducted for pairing properties of finite systems at nonzero temperature as predicted by the exact solutions of the pairing problem embedded in three principal statistical ensembles, as well as the unprojected…
A new variational method for studying the equilibrium states of an interacting particles system has been proposed. The statistical description of the system is realized by means of a density matrix. This method is used for description of…
Using the renormalization group method, new type of fluctuation-driven first order phase transitions and critical phenomena are predicted for certain classes of ferromagnetic superconductors and superfluids with unconventional…
We examine the role of the anisotropy of superconducting thermal critical fluctuations in the opening of pseudogaps in quasi-two dimensions. When the anisotropy of coherence or correlation lengths of the fluctuations is large enough and…
For certain complex superconducting systems, the superconducting properties get enhanced under mesoscopic point contacts made of elemental non-superconducting metals. However, understanding of the mechanism through which such contact…
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…
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…