Related papers: Debye temperature in LaHx-LaDy superconductors
A theoretical model involving phonon and lochon (local charged boson) mediated pairing of electrons in Pd(H/D)x is suggested to explain the possible observation of superconductivity in the range 51K < Tc < 295K (when x exceeds unity). In…
Detailed temperature dependence of both superconducting gaps was obtained directly by means of SnS-Andreev spectroscopy. The \Delta \sigma,\pi(T) -curves were shown to be deviated from standard BCS-like behavior, due to k-space proximity…
A superconductor is a material that can conduct electricity with no resistance below its critical temperature (Tc). The highest Tc that has been achieved in cuprates1 is 133 K at ambient pressure2 and 164 K at high pressures3. As the nature…
Recent studies of hydrogen-dominant (superhydride) materials, such as LaH10 have led to putative discoveries of near-room temperature superconductivity at high pressures, with a superconducting transition temperature (Tc) of 250 K observed…
Single-crystals of Cr and Cr3%Mn doped with ca. 0.2 at.% 119Sn were studied by means of 119Sn-site M\"ossbauer spectroscopy. M\"ossbauer spectra recorded in the temperature range of 78-300 K were analyzed using a hyperfine field…
A translation-invariant (TI) bipolaron theory of superconductivity based, like Bardeen-Cooper-Schrieffer theory, on Fr\"ohlich Hamiltonian is presented. Here the role of Cooper pairs belongs to TI bipolarons which are pairs of spatially…
Heat transport in bulk materials is well described using the Debye theory of 3D vibrational modes (phonons) and the acoustic match model. However, in cryogenic nanodevices, phonon wavelengths exceed device dimensions, leading to confinement…
Very recently a new family of layered materials, containing BiS2 planes was discovered to be superconducting at temperatures up to Tc=10 K, raising questions about the mechanism of superconductivity in these systems. Here, we present…
We present simple qualitative estimates for the maximal superconducting transition temperature, which may be achieved due to electron - phonon coupling in Eliashberg-McMillan theory. It is shown that in the limit of very strong coupling the…
We compare two effective phonon theories, which have both been applied recently to study heat conduction in anharmonic lattices. In particular, we study the temperature dependence of the thermal conductivity of the Fermi-Pasta-Ulam model…
We report an enhancement of thermal conductivity ($\kappa$) below the superconducting transition temperature ($T_C$) in the high carrier density $\beta$-V$_{1-x}$Ti$_x$ alloys. We find that the point defects generated when Ti is added to V…
Temperature gradients drive asymmetric ion distributions via thermodiffusion (the Soret effect), leading to deviations from the classical Debye--H\"uckel potential.We introduce the Eastman entropy of transfer, $\hat{S}_\pm = \alpha_\pm…
We have studied the origin of excess noise in superconducting transition-edge sensors (TES) with several different detector designs. We show that most of the observed noise and complex impedance features can be explained by a thermal model…
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…
We introduce a contactless technique for probing superconductivity, metal-insulator transitions, and magnetic ordering in micron-sized samples under extreme pressure. Utilizing a multistage Lenz lens system, directly sputtered onto diamond…
Unconventional superconductivity in bilayer graphene has been reported for twist angles $\theta$ near the first magic angle and charged electrostatically with holes near half filling of the lower flat bands. A maximum superconducting…
The superconducting transition temperature, T$_{C}$, the residual resistivity $\rho_{0}$ and the slope of resistivity curve at high temperature, d$\rho$/dT, have been measured in a series of MgB$_{2}$ samples that have been chemically…
We report $^{11}$B-NMR study on Al-doped MgB$_2$ that addresses a possible mechanism for a high superconducting (SC) transition temperature ($T_c$) of $\sim 40$ K in recently discovered MgB$_2$. The result of nuclear spin lattice relaxation…
In a recent contribution to this journal, it was shown that the transition temperatures of optimal high-Tc compounds obey the algebraic relation, Tc0 = kB-1{\beta}/\ell{\zeta}, where \ell is related to the mean spacing between interacting…
A recent experiment by Shimizu et al. has provided evidence of a superconducting phase in hcp Fe under pressure. To study the pressure-dependence of this superconducting phase we have calculated the phonon frequencies and the…