相关论文: Electron-Phonon Coupling Mode in Excitonic Insulat…
Quantum emitters in two-dimensional hexagonal boron nitride (h-BN) have generated significant interest due to observations of ultra-bright emission made at room temperature. The expectation that solid-state emitters exhibit broad…
We report first principles calculations of the electronic structure and electron-phonon coupling in the non-centrosymmetric superconductor LaNiC$_2$. These show that the material is a conventional electron-phonon superconductor with…
The phonon and electronic properties, the Eliashberg function and the temperature dependence of resistance of electride Ca2N are investigated by the DFT-LDA plane-wave method. The phonon dispersion, the partial phonon density of states and…
I present the results of first principles calculations of the phonon dispersions and electron-phonon coupling for BaTi$_2$Sb$_2$O. The phonon dispersions show a weak lattice instability near the zone corners that leads to a charge-density…
The dream of room temperature superconductors has inspired intense research effort to find routes for enhancing the superconducting transition temperature (Tc). Therefore, single-layer FeSe on a SrTiO3 substrate, with its extraordinarily…
The electron-phonon coupling of LaO$_{1-x}$F$_x$FeAs is re-investigated on the basis of density functional theory in local density approximation. The implications of the $(\pi,\pi)$ nesting of the Fermi surfaces are carefully studied and…
Tetragonal Ta2Se is a layered, Ta-rich chalcogenide that departs from conventional MX2 transition-metal dichalcogenides by hosting dense Ta-Ta networks capped by Se square-net layers. Here, we present a unified first-principles…
Superconductors without inversion symmetry in their crystal structure are known to exhibit unconventional properties. Recently, based on the measured temperature dependence of the magnetic field penetration depth, superconductivity in…
We predict a phase transition in freestanding monolayer Xenes from the semiconducting phase to the excitonic insulating (EI) phase can be induced by reducing an external electric field below some critical value which is unique to each…
Quantum spin Hall insulators (QSHIs) and excitonic insulators (EIs) are prototypical topological and correlated states of matter, respectively. The topological phase transition between the two has attracted much theoretical interest but…
We present a theoretical study of electron-phonon scattering effects in thin films made of a strong topological insulator. Phonons are modelled by isotropic elastic continuum theory with stress-free boundary conditions, and the interaction…
We report on the optical excitation spectra in Sr$_2$VO$_4$. The phonon modes are assigned and their evolution with temperature is discussed in the frame of the different phase transitions crossed upon cooling. Besides the expected…
The pairing mechanism in iron-based superconductors is believed to be unconventional, i.e. not phonon-mediated. The achieved transition temperatures Tc in these superconductors are still significantly below those of some of the cuprates,…
We studied the optical properties of antiferromagnetic ZnCr2Se4 by infrared spectroscopy up to 28,000 cm-1 and for temperatures from 5 to 295 K. At the magnetic phase transition at 21 K, one of the four phonon modes reveals a clear…
Bound electron-hole pairs in semiconductors known as excitons can form a coherent state at low temperatures akin to a BCS condensate. The resulting phase is known as the excitonic insulator and has superfluid properties. Here we…
The interaction of a single-cycle THz electric field with the topological insulator $\mathrm{MnBi}_2\mathrm{Te}_4$ triggers strongly anharmonic lattice dynamics, promoting fully coherent energy transfer between the otherwise non-interacting…
The ability to assemble layers of two-dimensional (2D) materials to form permutations of van der Waals heterostructures provides significant opportunities in materials design and synthesis. Interlayer interactions provide a path to new…
We explore the collective response in an excitonic insulator phase in Ta$_2$NiSe$_5$ using a semirealistic model including relevant lattice and electronic instabilities. We calculate order-parameter susceptibility and Raman response within…
The bulk tin selenide (SnSe) is the best thermoelectric material currently with the highest figure-of-merit due to the strong phonon-phonon interactions. We investigate the effect of electron-phonon coupling (EPC) on the transport…
Two-dimensional moir\'e materials have emerged as the most versatile platforms for realizing quantum phases of electrons. Here, we explore the stability origins of correlated states in WSe2/WS2 moir\'e superlattices. We find that ultrafast…