Related papers: Multiband Superconductivity in Heavy Fermion Compo…
Superconductivity has been first observed in TlNi$_2$Se$_2$ at T$_C$=3.7 K and appears to involve heavy electrons with an effective mass $m^*$=14$\sim$20 $m_b$, as inferred from the normal state electronic specific heat and the upper…
The superconducting properties of a recently discovered high $T_{\rm c}$ superconductor, Sr/ammonia-intercalated FeSe, have been measured using pulsed magnetic fields down to $4.\,\rm {K}$ and muon spin spectroscopy down to $1.5\,\rm K$.…
The discovery of high-temperature superconductivity in compressed H3S by Drozdov and co-workers (A. Drozdov, et. al., Nature 525, 73 (2015)) heralded a new era in superconductivity. To date, the record transition temperature of Tc = 260 K…
We report 75As-NMR study on the Fe-pnictide high-Tc superconductor Y0.95La0.05FeAsO_{1-y} (Y0.95La0.051111) with Tc=50 K that includes no magnetic rare-earth elements. The measurement of the nuclear-spin lattice-relaxation rate 75(1/T1) has…
The superconducting order parameter of the first heavy-fermion superconductor CeCu2Si2 is currently under debate. A key ingredient to understand its superconductivity and physical properties is the quasiparticle dispersion and Fermi…
Topological materials which are also superconducting are of great current interest, since they may exhibit a non-trivial topologically-mediated superconducting phase. Although there have been many reports of pressure-tuned or…
Low-temperature (down to $\sim$ 50 mK) thermal conductivity measurements with the heat flow direction along the inter-plane tetragonal $c$-axis, $\kappa_c$, were used to study the superconducting state of heavy fermion CeIrIn$_5$.…
Bulk FeSe is superconducting with a critical temperature $T_c$ $\cong$ 8 K and SrTiO$_3$ is insulating in nature, yet high-temperature superconductivity has been reported at the interface between a single-layer FeSe and SrTiO$_3$. Angle…
We report resistivity $\rho$ and thermal conductivity $\kappa$ measurements on Ca$_3$Ir$_4$Sn$_{13}$ single crystals, in which superconductivity with $T_c \approx 7$ K was claimed to coexist with ferromagnetic spin-fluctuations. Among three…
The density-of-states at the Fermi energy, $N(E_F)$, is low in doped superconducting semiconductors and high-$T_C$ cuprates. This contrasts with the common view that superconductivity requires a large electron-boson coupling $\lambda$ and…
In unconventional superconductors, it is generally believed that understanding the physical properties of the normal state is a pre-requisite for understanding the superconductivity mechanism. In conventional superconductors like niobium or…
Inelastic neutron scattering (INS) is employed to study damped spin-wave excitations in the noncentrosymmetric heavy-fermion superconductor CePt3Si along the antiferromagnetic Brillouin-zone boundary in the low-temperature magnetically…
Unconventional superconductivity and in particular triplet superconductivity have been front and center of topological materials and quantum technology research. Here we report our observation of triplet superconductivity in nonmagnetic…
The results of heat capacity C_p(T, H) and electrical resistivity \rho(T,H) measurements down to 0.35 K as well as muon spin relaxation and rotation (\muSR) measurements on a noncentrosymmetric superconductor LaIrSi3 are presented. Powder…
We report on measurements of the temperature dependence of the magnetic penetration depth of a very high quality single crystal of nonmagnetic superconductor LaPt3Si without inversion symmetry. The results are compared with those previously…
We report detailed Seebeck coefficient, Hall resistivity as well as specific heat measurement on Ca$_3$Ir$_4$Sn$_{13}$ single crystals. The Seebeck coefficient exhibits a peak corresponding to the anomaly in resistivity at $T^*$, and the…
Recently, a new type of unconventional superconductivity with a field-induced transition between two different superconducting (SC) states was discovered in the heavy fermion system CeRh$_{2}$As$_{2}$. This unusual SC state was proposed to…
We report the $^{121/123}$Sb-NMR/nuclear quadrupole resonance (NQR) measurements on the newly-discovered superconductor BaTi$_2$Sb$_2$O with a two-dimensional Ti$_2$O square-net layer formed with Ti$^{3+}$ (3$d^1$). NQR measurements…
We investigate the robustness against disorder of superconductivity in multiband systems where the fermions have four internal degrees of freedom. This permits unconventional $s$-wave pairing states, which may transform nontrivially under…
We have synthesized polycrystalline samples of the noncentrosymmetric superconductor Mo3Al2C by arc and RF melting, measured its transport, magnetic and thermodynamic properties, and computed its band structure. Experimental results…