Related papers: Composite Superconducting Orders and Magnetism in …
High-pressure magnetization, structural and 57Fe M\"ossbauer studies were performed on superconducting Rb0.8Fe1.6Se2.0 with Tc = 32.4 K. The superconducting transition temperature gradually decreases on increasing pressure up to 5.0 GPa…
At temperatures much lower than its superconducting critical temperature $T_c$ of 2.1 K, the heavy fermion superconductor UTe$_2$ has a remarkable phase diagram of magnetic field $H$ vs. angles $\phi$ and $\theta$ at which $H$ is tilted…
Recently, evidence has emerged for a field-induced even- to odd-parity superconducting phase transition in CeRh$_2$As$_2$ [S. Khim et al., Science 373 1012 (2021)]. Here we argue that the P4/nmm non-symmorphic crystal structure of…
The interplay of charge orders with superconductivity in underdoped cuprates at high magnetic fields ($H$) is an open question, and even the value of the upper critical field ($H_{c2}$), a measure of the strength of superconductivity, has…
We report the novel pressure(P)-temperature(T) phase diagrams of antiferromagnetism (AF) and superconductivity (SC) in CeRhIn$_5$, CeIn$_3$ and CeCu$_2$Si$_2$ revealed by the NQR measurement. In the itinerant helical magnet CeRhIn$_5$, we…
We report on systematic evolutions of antiferromagnetic (AFM) spin fluctuations and unconventional superconductivity (SC) in heavy-fermion (HF) compounds CeRh$_{1-x}$Ir$_{x}$In$_5$ via $^{115}$In nuclear-quadrupole-resonance (NQR)…
Magnetic susceptibility, electrical resistivity and heat capacity data for single crystals of Ce(Rh,Ir)1-x(Co,Ir)xIn5 (0 < x < 1) have allowed us to construct a detailed phase diagram for this new family of heavy-fermion…
In materials without an inversion center of symmetry the spin degeneracy of the conducting band is lifted by an antisymmetric spin orbit coupling (ASOC). Under such circumstances, spin and parity cannot be separately used to classify the…
We focus on a broad class of tetragonal itinerant systems sharing a tendency towards the spontaneous formation of incommensurate magnetism with ordering wavevectors $\mathbf{Q}_{1,2}=(\pi-\delta,0)/(0,\pi-\delta)$ or…
When subjected to pressure, the prototypical heavy-fermion antiferromagnet CeRhIn5 becomes superconducting, forming a broad dome of superconductivity centered around 2.35 GPa (=P2) with maximal Tc of 2.3 K. Above the superconducting dome,…
In matter, any spontaneous symmetry breaking induces a phase transition characterized by an order parameter, such as the magnetization vector in ferromagnets, or a macroscopic many-electron wave-function in superconductors. Phase…
I review the principal theories that have been proposed for the superconducting phases of UPt$_3$. The detailed H-T phase diagram places constraints on any theory for the multiple superconducting phases. I comment on the limitations of the…
The order parameter and pairing mechanism for superconductivity in heavy fermion compounds are still poorly understood. Scanning tunneling microscopy and spectroscopy at ultra-low temperatures can yield important information about the…
The behavior of the so-called weak moment antiferromagnetic states, observed in the heavy-fermion superconductors UPt$_3$ and URu$_2$Si$_2$, is discussed in view of recent $\mu$SR results obtained as function of control parameters like…
The coexistence of magnetism and superconductivity in the isovalent-P-substituted BaFe$_2$(As$_{1-x}$P$_x$)$_2$ has been investigated microscopically by $^{31}$P-NMR measurements. We found that superconducting (SC) transition occurs in a…
The discovery of superconductivity in LaFeAsO introduced the ferropnictides as a major new class of superconducting compounds with critical temperatures second only to cuprates. The presence of magnetic iron makes ferropnictides radically…
Recent angle-resolved photoemission spectroscopy (ARPES) and density functional theory plus Hubbard $U$ (DFT+$U$) studies revealed that a heavy-fermion superconductor CeRh$_2$As$_2$ exhibits van Hove singularities and the Dirac point near…
Since its discovery, iron-based superconductivity has been known to develop near an antiferromagnetic order, but this paradigm fails in the iron chalcogenide FeSe, whose single-layer version holds the record for the highest superconducting…
We study the order parameter symmetry in a hexagonal crystal with co-existing superconductivity and ferromagnetism. An experimental example is provided by carbon-based materials, such as graphite-sulfur composites, in which an evidence of…
In this review, we present a summary of experimental studies of magnetism in Fe-based superconductors. The doping dependent phase diagram shows strong similarities to the generic phase diagram of the cuprates. Parent compounds exhibit…