相关论文: Two-dimensional vortex behavior in highly underdop…
We present a systematic study of the Hall conductance in Bi$_2$Sr$_2$CaCu$_2$O$_x$ (Bi2212) thin films over a large range of doping. We find that in a large part of the phase diagram the Hall coefficient changes sign as a function of…
We have measured the dynamics of individual magnetic fluxoids entering and leaving photolithographically patterned thin film rings of the underdoped high-temperature superconductor Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$, using a variable sample…
Thin films of the high-temperature superconductor HgBa$_2$CaCu$_2$O$_{6+\delta}$ have been prepared on SrTiO$_3$ substrates by pulsed-laser deposition of precursor films and subsequent annealing in mercury-vapor atmosphere. The…
Similar to the optimal-doped, weak-ferromagnetic (WFM induced by canted antiferromagnetism, T$_{Curie}$ = 131 K) and superconducting (T$_{c}$ = 56 K) RuSr$_{2}$GdCu$_{2}$O$_{8}$, the underdoped RuSr$_{2}$EuCu$_{2}$O$_{8}$ (T$_{Curie}$ = 133…
The magnetization of three high-quality single crystals of YBa$_{2}$Cu$_{3}$O$_{6+x}$, from slightly overdoped to heavily underdoped,has been measured using torque magnetometry. Striking effects in the angular dependence of the torque for…
Infrared spectroscopy has been used to investigate the temperature dependence and c-axis magnetic field dependence of the Josephson plasma resonance in optimally doped Tl2Ba2CaCu2O8 thin films, and underdoped YBa2Cu3O6.5 ortho - II single…
We present the transport studies of field variation of the pinning force for the flux motion across the twin boundaries in YBaCuO single crystals. It is found that the depinning current J_c decreases with an increase in the magnetic field…
Mass of Abrikosov vortices defied experimental observation for more than four decades. We demonstrate a method of its detection in high-temperature superconductors. Similarly to electrons, fluxons circulate in the direction given by the…
The reflectance of high-quality, unpolished single crystals of YBa_2Cu_3O_{6+x}, for the doping range x=0.50 -> 0.95, has been measured with radiation polarized along the c axis from approx 50 cm^{-1} to 5000 cm^{-1} between 10 K and 300 K.…
The thermal conductivity kappa of the layered s-wave superconductor NbSe_2 was measured down to T_c/100 throughout the vortex state. With increasing field, we identify two regimes: one with localized states at fields very near H_c1 and one…
It is shown that there are three kinds of vortices in a superconductor; a vortex with the fluxoid quantum 1 (VF), a new vortex with 0 (VZF), and a vortex with -1 (VAF), respectively. The Hall field via three vortices is studied and found to…
The properties of RbBi$_2$, a 4.15 K superconductor, were investigated using magnetic field, pressure and neutron diffraction. Under hydrostatic pressure, an almost 50 % reduction of T$_c$ is observed, linked to a low Debye temperature…
High-Tc superconducting materials (HTSC) have anomalous properties such as the pseudo-gap or spin-gap etc., in Hall coefficient, 1/T1T and the density of states etc. First including effects of strong on-site repulsion between d-electrons at…
The in-plane $\rho_{ab}(H,T)$ and the out-of-plane $\rho_c(H,T)$ magneto-transport in magnetic fields up to 28 T has been investigated in high quality non-superconducting (down to 20 mK) La-free Bi$_{2+x}$Sr$_{2-x}$CuO$_{6+\delta}$ single…
To investigate the origin of the enhanced $T_c$ ($\approx$ 110 K) of the trilayer cuprate superconductor Bi$_{2}$Sr$_{2}$Ca$_{2}$Cu$_{3}$O$_{10+\delta}$ (Bi-2223), we have performed systematic magnetoresistance (MR) measurements on this…
The layered compound $\gamma$-PtBi$_2$ is a topological semimetal with Fermi arcs at the surface joining bulk Weyl points. Recent work has found signatures of surface superconductivity consisting of gap openings compatible with a critical…
We report on the scaling of transport properties around the vortex melting in YBa$_2$Cu$_3$O$_{7- \delta}$ oriented-twin single crystals in applied magnetic fields between 1T and 18T. We find that for all the measured field range the linear…
Using micro-bridge technique, we have studied the vortex dynamics in a very low temperature region (i.e. T/Tc -> 0) of the B-T phase diagram of Bi_2Sr_2Ca_1Cu_2O_{8+\delta} single crystal. We distinguish two types of vortex dynamics near…
In- and out-of-plane optical spectra and specific heat measurements for the single layer cuprate superconductor Hg-1201 at optimal doping (Tc = 97 K) are presented. Both the in-plane and out-of-plane superfluid density agree well with a…
Low magnetic field scanning tunneling spectroscopy of individual Abrikosov vortices in heavily overdoped Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ unveils a clear d-wave electronic structure of the vortex core, with a zero-bias conductance peak at…