Related papers: Evidence for ferromagnetic spin-pairing supercondu…
The formation of electron pairs is a prerequisite of superconductivity. The fermionic nature of electrons yields four classes of superconducting correlations with definite symmetry in spin, space and time. Here, we suggest double quantum…
Identification of pairing mechanisms leading to the unconventional superconductivity realized in copper-oxide, heavy-fermions, and organic compounds is one of the most challenging issues in condensed-matter physics. Clear evidence for an…
We report first-principles and strongly-correlated calculations of the newly-discovered heavy fermion superconductor UTe$_2$. Our analyses reveal three key aspects of its magnetic, electronic, and superconducting properties, that include:…
We report $^{123}$Sb nuclear quadrupole resonance (NQR) measurements of the filled skutterudite heavy-fermion superconductor PrOs$_4$Sb$_{12}$ under high pressures of 1.91 and 2.34 GPa. The temperature dependence of NQR frequency and the…
The exotic normal state of iron chalcogenide superconductor FeSe, which exhibits vanishing magnetic order and possesses an electronic nematic order, triggered extensive explorations of its magnetic ground state. To understand its novel…
In this paper we propose that electron spin resonance (ESR) measurements enable us to detect the long-range spin nematic order. We show that the frequency of the paramagnetic resonance peak in the ESR spectrum is shifted by the…
The unusual quantum-disordered magnetic ground state intertwined with superconductivity and electronic nematicity in FeSe has been a research focus in iron-based superconductors. However, the intrinsic spin excitations across the entire…
It is shown that unconventional nature of superconducting state of PrOs_4Sb_12, a Pr-based heavy electron compound with the filled-Skutterudite structure, can be explained in a unified way by taking into account the structure of the…
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…
In europium-based iron pnictides superconducting Fe-planes can be influenced by a Zeeman field originated from the neighboring Eu-planes. The field tends to induce spin-density waves with a ferromagnetic average which coexists with the…
Recently, several measurements of the nuclear spin lattice relaxation rate $T_{1}^{-1}$ in the newly discovered superconducting Fe-pnictides have been reported. These measurements generally show no coherence peak below $T_{c}$ and indicate…
We discover a robust coexistence of superconductivity and ferromagnetism in an iron arsenide RbEuFe$_4$As$_4$. The new material crystallizes in an intergrowth structure of RbFe$_2$As$_2$ and EuFe$_2$As$_2$, such that the Eu sublattice turns…
The novel spin-triplet superconductor candidate UTe2 was discovered only recently at the end of 2018 and attracted enormous attention. We review key experimental and theoretical progress which has been achieved in different laboratories.…
We report a novel superconducting (SC) and antiferromagnetic (AF) hybrid state in SrFe2As2 revealed by 75As nuclear magnetic resonance (NMR) experiments on a single crystal under highly hydrostatic pressure up to 7 GPa. The NMR spectra at…
We explore the pairing state and gap structure of UTe$_2$ using a six-orbital model which we call the $f$-$d$-$p$ model. Our model accurately reproduces the quasi-two-dimensional Fermi surfaces consistent with recent de Haas-van Alphen…
It is shown that anomalous properties of UGe_2 can be understood in a unified way on the basis of a single assumption that the superconductivity is mediated by the coupled SDW and CDW fluctuations induced by the imperfect nesting of the…
Kondo hybridization in partially filled f-electron systems conveys significant amount of electronic states sharply near the Fermi energy leading to various instabilities from superconductivity to exotic electronic orders. UGe2 is a 5f heavy…
Symmetry properties of the order parameter are among the most fundamental characteristics of a superconductor. The pairing symmetry of recently discovered heavy fermion superconductor UTe2 featuring an exceedingly large upper critical field…
We study transport in ferromagnetic-superconductor/normal-metal systems. It is shown that charge and spin currents are pumped from ferromagnetic superconductors into adjacent normal metals by adiabatic changes in the order parameters…
We present a high-pressure NMR study of the overdoped iron pnictide superconductor NaFe$_{0.94}$Co$_{0.06}$As. The low-energy antiferromagnetic spin fluctuations in the normal state, manifest as the Curie-Weiss upturn in the spin-lattice…