Related papers: Properties of Odd-Frequency Superconductivity in A…
The heavy fermion superconductor CeCoIn_5 can be tuned between superconducting and antiferromagnetic ground states by hole doping with Cd. Nuclear magnetic resonance (NMR) data indicate that these two orders coexist microscopically with an…
We investigate the emergence and consequences of odd-frequency spin-triplet s-wave pairing in superconducting hybrid junctions at the edge of a two-dimensional topological insulator without any magnetism. More specifically, we consider…
A possibility of the odd-frequency pairing in the strong-coupling electron-phonon systems is discussed. Using the Holstein-Hubbard model, we demonstrate that the anomalously soft Einstein mode with the frequency $\omega_{\rm…
This paper describes the first 63-Cu NMR study of an electron-doped infinitely-layered high Tc superconductor Sr$_0.9$La$_0.1$CuO$_2$ (Tc=42K). The spin dynamics in the normal state above Tc exhibits qualitatively the same behavior as some…
Spin-fluctuation-mediated unconventional superconductivity can emerge at the border of magnetism, featuring a superconducting order parameter that changes sign in momentum space. Detection of such a sign-change is experimentally…
Superconductivity in three dimensions is almost universally governed by Ginzburg-Landau mean field theory, with critical fluctuations typically confined to within a few percent of the transition temperature ($T_{\rm c}$). We report that the…
The mechanism of incommensurate (IC) spin-density-wave (SDW) order observed in the Flude-Ferrell-Larkin-Ovchinnikov (FFLO) phase of CeCoIn$_5$ is discussed on the basis of new mode-coupling scheme among IC-SDW order, two superconducting…
We show that the recently observed spin resonance modes in heavy-fermion superconductors CeCoIn$_5$ and CeCu$_2$Si$_2$ are magnetic excitons originating from superconducting quasiparticles. The wave vector ${\bf Q}$ of the resonance state…
We give a review of recent results on the heavy fermion superconductor CeRhIn$_5$ which presents ideal conditions to study the interplay of antiferromagnetism and superconductivity. The main results are the appearance of domains of…
We report ^{75}As nuclear magnetic resonance studies on an underdoped single-crystal Ba0.77K0.23Fe2As2 with Tc = 16.5 K. Below T_N = 46 K, the NMR peaks for H//c split and those for H //a shift to higher frequencies, which indicates that an…
The superconducting (SC) state ($T_\mathrm{c}$ = 0.3 K) of the heavy-fermion compound CeRh$_2$As$_2$, which undergoes an unusual field-induced transition to another high-field SC state, emerges from an unknown ordered state below…
We study s-wave superconductivity in the attractive Hubbard model in an applied magnetic field and assume the extreme Pauli limit where the orbital critical field is much greater than the Zeeman critical field. We work at a coupling…
A key aspect of unconventional pairing by the antiferromagnetic spin-fluctuation mechanism is that the superconducting energy gap must have opposite sign on different parts of the Fermi surface. Recent observations of non-nodal gap…
We carried out specific-heat and ac-susceptibility experiments under hydrostatic pressure to investigate the interplay of spin-density-wave antiferromagnetism (A) and superconductivity (S) in single-crystalline AS-type CeCu2Si2. We find…
We study the superconductivity of spin-polarized electrons in centrosymmetric ferromagnetic metals. Due to the spin-polarization and the Fermi statistics of electrons, the superconducting pairing function naturally has odd parity. According…
Varying the angle Theta between applied field and the conducting planes of a layered superconductor in a small interval close to the plane-parallel field direction, a large number of superconducting states with unusual properties may be…
If the topological insulator Bi$_{2}$Se$_{3}$ is doped with electrons, superconductivity with $T_{{\rm c}}\approx3-4\:{\rm K}$ emerges for a low density of carriers ($n\approx10^{20}{\rm cm}^{-3}$) and with a small ratio of the…
The study of competing ground states is a central issue in condensed matter physic. In this article we will discuss the interplay of antiferromagnetic order and unconventional superconductivity in Ce based heavy-fermion compounds. In all…
It is theoretically shown that, in the four-fold symmetric d-wave superconducting phase, a paramagnetic pair-breaking (PPB) enhanced sufficiently by increasing the applied magnetic field induces not only the Fulde-Ferrell-Larkin-Ovchinnikov…
Pairing symmetry in the superconducting state coexisting with antiferromagnetic order is studied based on a microscopic theory. We calculate the linearized Eliashberg's equation within the random phase approximation in the Hubbard model…