Related papers: Dynamical Cooper pairing in non-equilibrium electr…
It is usually believed that the spin-fluctuation mechanism for high-temperature superconductivity results in d-wave pairing, and that it is destructive for the conventional phonon-mediated pairing. We show that in bilayer materials, due to…
Despite the intensive efforts for determining the mechanism that causes high-temperature superconductivity in copper oxide materials, no consensus on the pairing mechanism has been reached. Recent advances in high resolution angle-resolved…
Ultrafast optical excitation is known to destabilize long-range order in correlated systems, yet experiments have also reported the emergence of metastable phases, in some cases with enhanced critical temperatures. The microscopic origin of…
A possibility of the odd-frequency pairing in the strong-coupling electron-phonon systems is discussed. Using the Holstein-Hubbard model, we demonstrate that the anomalously soft Einstein mode with the frequency $\omega_{\rm…
We report on fluctuations in the electron system, Cooper pairs and quasiparticles, of a superconducting aluminium film. The superconductor is exposed to pair-breaking photons (1.54 THz), which are coupled through an antenna. The change in…
The change-over from phase- to amplitude-fluctuation driven superconductivity is examined for a composite system of free electrons (Fermions with concentration n_F) and localized electron-pairs (hard-core Bosons with concentration n_B) as a…
The electron-phonon interaction is a major factor influencing the competition between collective instabilities in correlated-electron materials, but its role in driving high-temperature superconductivity in the cuprates remains poorly…
Identifying the mechanism of superconductivity in the high-temperature cuprate superconductors is one of the major outstanding problems in physics. We report local measurements of the onset of superconducting pairing in the high-transition…
Superconductivity and ferroelectricity,representing two distinct forms of ordered states, are typically not found together in the same system, making it even more difficult to create a connection between them. Here, supported by…
The study of mechanisms for enhancing superconductivity has been a central topic in condensed matter physics due to the combination of fundamental and technological interests. One promising route is to exploit non-equilibrium effects in the…
Electron-phonon coupling, being one of the most important parameters governing the material evolution after ultrafast energy deposition, yet remains the most unexplored one. In this work, we applied the dynamical coupling approach to…
Breaking down the traditional perception on phonons which are achiral, the recent discovery of chiral phonon carrying angular momentum provides possible ways to couple electron, photon, spin, magnon and exciton, etc. We theoretically…
In conventional Bardeen-Cooper-Schrieffer (BCS) superconductors, electrons with opposite momenta bind into Cooper pairs due to an attractive interaction mediated by phonons in the material. While superconductivity naturally emerges at…
We analyze the quantum dynamics of two electromagnetic oscillators coupled in series to a voltage biased Josephson junction. When the applied voltage leads to a Josephson frequency across the junction which matches the sum of the two mode…
The surprising discovery of superconductivity in layered iron-based materials, with transition temperatures climbing as high as 55 K, has lead to thousands of publications on this subject over the past two years. While there is general…
We study the role of the superconducting proximity effect on the electron-phonon energy exchange in diffusive normal metals (N) attached to superconductors (S). The proximity effect modifies the spectral response of the normal metal, in…
I construct a simple model to demonstrate that when the many-electron quantum state of a material is near a quantum phase transition and the vibrational motion of a phonon explores the potential energy surface near the transition point,…
We show that an interacting electronic system with a single ordinary or extended Van Hove point, which crosses the Fermi energy, is unstable against triplet superconductivity. The pairing mechanism is unconventional. There is no Cooper…
Strong laser pulses can control superconductivity, inducing non-equilibrium transient pairing by leveraging strong-light matter interaction. Here we demonstrate theoretically that equilibrium ground-state phonon-mediated superconductive…
Using a nonequilibrium implementation of the Lanczos-based exact diagonalisation technique we study the possibility of the light-induced superconducting phase coherence in a solid state system after an ultrafast optical excitation. In…