Related papers: A comprehensive study of bond bipolaron supercondu…
Polaron and bipolaron formation in the Holstein-Hubbard model with harmonic confinement potential, relevant to quantum dot structures, is investigated in one to three dimensions by means of unbiased quantum Monte Carlo simulations. The…
The subject of the present study is the double-layer square-lattice system with the intralayer phonon modulations. We investigate the superconducting and excitonic pairings, as well as their coexistence, as functions of various physical…
Graphene moire superlattices are outstanding platforms to study correlated electron physics and superconductivity with exceptional tunability. However, robust superconductivity has been measured only in magic-angle twisted bilayer graphene…
Inelastic x-ray scattering and $ab$-$initio$ calculation are applied to investigate the lattice dynamics and electron-phonon coupling of the ternary silicide superconductor CaAlSi ($P/bar{6}m2$). A soft c-axis polarized mode is clearly…
We present a systematic investigation of superconductivity in a topological superconductor candidate $T_{\rm d}$-MoTe$_2$ in the few-layer limit. By examining multiple mechanically exfoliated samples with different thicknesses, substrates…
A half-filled-band Hubbard model on an anisotropic triangular lattice (t in two bond directions and t' in the other) is studied using an optimization variational Monte Carlo method, to consider the Mott transition and superconductivity…
We have studied the lattice dynamics, electron-phonon coupling, and superconducting properties of $\alpha$-MoB$_2$, as a function of applied pressure, within the framework of density functional perturbation theory using a mixed-basis…
Topological phononic insulators are the counterpart of three-dimensional quantum spin Hall insulators in phononic systems and, as such, their topological surfaces are characterized by Dirac cone-shaped gapless edge states arising as a…
We study a three-orbital Su-Schrieffer-Heeger model defined on a two-dimensional Lieb lattice and in the negative charge transfer regime using determinant quantum Monte Carlo. At half-filling (1 hole/unit cell), we observe a bipolaron…
In this Colloquium, the main features of the electron-lattice interaction are discussed and high values of the critical temperature up to room temperature could be provided. While the issue of the mechanism of superconductivity in the high…
The quest to govern the driving forces behind superconductivity and gain control over the superconducting transition temperature $T_{c}$ is as old as the phenomenon itself. Microscopically, this requires a proper understanding of the…
We study a simple electron-phonon model on square and triangular versions of the Lieb-lattice using an asymptotically exact strong coupling analysis. At zero temperature and electron density $n = 1$ (one electron per unit cell), for various…
We present the first numerically exact study of a polaron with quadratic coupling to the oscillator displacement, using two alternative methodological developments. Our results cover both anti-adiabatic and adiabatic regimes and the entire…
We study the superconductivity of strongly coupled electron-phonon systems where the geometry of the lattice frustrates the charge order by the sign-problem-free Quantum Monte Carlo(QMC) method. The results suggest that with charge order…
Superconductivity in hole-doped Li_xNbO_2 has been reported with T_c ~ 5 K in the range 0.45 < x < 0.8. The electronic structure is based on a two-dimensional triangular Nb lattice. The strong trigonal crystal field results in a single Nb…
The mechanisms for strong electron-phonon coupling predicted for hydrogen-rich alloys with high superconducting critical temperature ($T_c$) are examined within the Migdal-Eliashberg theory. Analysis of the functional derivative of $T_c$…
A one-third monolayer of the heavy metals Sn and Pb deposited on semiconductor substrates can lead to a $\sqrt{3}\times\sqrt{3}$ surface reconstruction, constituting an exciting triangular lattice material platform. A long history of…
Over the last decade several competing models of high-temperature superconductivity were proposed, most of them with short-range interactions. We review a more realistic model with strong on-site repulsive correlations, the Coulomb and…
We compute the properties of singlet and triplet bipolarons on two-dimensional lattices using the continuous time quantum Monte Carlo algorithm. Properties of the bipolaron including the total energy, inverse mass, bipolaron radius and…
We study within a first-principle approach the band structure, vibrational modes and electron-phonon coupling in boron, aluminum and phosphorus doped silicon in the diamond phase. Our results provide evidences that the recently discovered…