Related papers: Cavity engineered phonon-mediated superconductivit…
The discovery of the first high critical temperature (Tc) transition metal diboride superconductor, MgB2 structure alpha-MoB2 under pressure with Tc up to 32 K at 100 GPa, provides new input into some unexplained aspects of electron-phonon…
Recent experiments have revealed ultrastrong coupling between light and matter as a promising avenue for modifying material properties, such as electrical transport, chemical reaction rates, and even superconductivity. Here, we explore…
We propose an all-optical Moir\'e-like exciton confinement by means of spatially periodic optical cavities. Such periodic photonic structures can control the material properties by coupling the matter excitations to the confined photons and…
Optical driving of materials has emerged as a versatile tool to control their properties, with photo-induced superconductivity being among the most fascinating examples. In this work, we show that light or lattice vibrations coupled to an…
Emergence of superconductivity in a two-band system coupled with breathing and Jahn-Teller phonons is discussed in a weak-coupling limit. With the use of a standard quantum mechanical procedure, the phonon-mediated attraction is derived.…
The ground-state properties and excitation energies of a quantum emitter can be modified in the ultrastrong coupling regime of cavity quantum electrodynamics (QED) where the light-matter interaction strength becomes comparable to the cavity…
Ultrastrong light-matter coupling has traditionally been studied in optical cavities, where it occurs when the light-matter coupling strength reaches a significant fraction of the transition frequency. This regime fundamentally alters the…
We report inelastic neutron scattering measurements of the phonon density-of-states in Mg11B2, which has a superconducting transition at 39.2 K. The acoustic phonons extend in energy to 36 meV, and there are highly dispersive optic branches…
We present an experimental study on the cavity-atom ensemble system, and realize the doubly-resonant cavity enhanced electromagnetically induced transparency, where both the probe and control lasers are resonant with a Fabry-Perot cavity.…
We present a first principles investigation of the lattice dynamics and electron-phonon coupling of the superconductor MgB_2 and the isostructural AlB_2 within the framework of density functional perturbation theory using a mixed-basis…
Plasmonic excitations behave fundamentally different in layered materials in comparison to bulk systems. They form gapless modes, which in turn couple at low energies to the electrons. Thereby they can strongly influence superconducting…
Recently it was discovered that, under elevated pressures, MoB$_2$ exhibits superconductivity at a critical temperature, $T_c$, as high as 32 K. The superconductivity appears to develop following a pressure-induced structural transition…
We explore experimentally a quantum metamaterial based on a superconducting chip with 25 frequency-tunable transmon qubits coupled to a common coplanar resonator. The collective bright and dark modes are probed via the microwave response,…
Advances in light sources and time resolved spectroscopy have made it possible to excite specific atomic vibrations in solids and to observe the resulting changes in electronic properties but the mechanism by which phonon excitation causes…
Two-dimensional (2D) metals can host gapless plasmonic excitations, which strongly couple to electrons and thus may significantly affect superconductivity in layered materials. To investigate the dynamical interplay of the electron-electron…
We report on measurements of the specific heat of the recently discovered superconductor MgB$_2$ in the temperature range between 3 and 220 K. Based on a modified Debye-Einstein model, we have achieved a rather accurate account of the…
We develop a theory for light-induced superconductivity in underdoped cuprates in which the competing bond-density wave order is suppressed by driving phonons with light. Close to a bond-density wave instability in a system with a small…
State-of-the-art model Hamiltonians, like Fr\"ohlich's, or density functional theory approaches to electron-phonon interaction suffer from a severe overscreening error. This is due to the incorrect treatment of the screening of the ionic…
Since the discovery of MgB2 with Tc=39K, various metal diborides of MB2 have been intensively studied to find possible conventional high-temperature superconductors. A possible 2D structure of the metal diboride has been shown to be in the…
We study quantum effects of the vacuum light-matter interaction in materials embedded in optical cavities. We focus on the electronic response of a two-dimensional semiconductor placed inside a planar cavity. By using a diagrammatic…