Related papers: Multiple nodal superconducting phases and order-pa…
A structural orthorhombic-to-tetragonal phase transition was recently discovered in the heavy-fermion compound UTe$_2$ at a pressure $p^*\simeq3-8$~GPa [Honda \textit{et al.}, J. Phys. Soc. Jpn. \textbf{92}, 044702 (2023); Huston \textit{et…
A topological superconductor, characterized by either a chiral order parameter or a chiral topological surface state in proximity to bulk superconductivity, is foundational to topological quantum computing. As in other topological phases of…
We review recent progress in understanding the different spatial broken symmetries that occur in the normal states of the family of charge-transfer solids (CTS) that exhibit superconductivity (SC), and discuss how this knowledge gives…
The heavy fermion paramagnet UTe$_2$ exhibits numerous characteristics of spin-triplet superconductivity. Efforts to understand the microscopic details of this exotic superconductivity have been impeded by uncertainty regarding the…
To investigate spin susceptibility in a superconducting (SC) state, we measured the $^{125}$Te-nuclear magnetic resonance (NMR) Knight shifts at magnetic fields ($H$) up to 6.5 T along the $b$ and $c$ axes of single-crystal UTe$_2$, a…
The interplay among various collective electronic states such as superconductivity (SC) and charge density wave (CDW) is of tremendous significance in low-dimensional transition metal dichalcogenides. Thus far, a consensus on the…
We study spin-triplet superconductivity with both unitary and nonunitary pairing in the presence of an external Zeeman magnetic field. Within a mean-field framework, we exactly diagonalize the Bogoliubov-de Gennes Hamiltonian and derive…
The heavy-fermion superconductor UTe2 has attracted intense interest as a candidate for spin-triplet pairing. Recent scanning tunneling microscopy (STM) studies have reported complex charge orders (COs) on its (011) surface, but their…
The superconducting systems emerging from topological insulators upon metal ion intercalation or application of high pressure are ideal for investigation of possible topological superconductivity. In this context, Sr-intercalated…
The mechanism of the unconventional topological superconductivity (TSC) remains a long-standing issue. We investigate the quantum phase diagram of the extended $t$-$J$-$J_{\chi}$ model including spin chiral interactions on triangular…
We study the spin-orbit coupling in spin-triplet Cooper pairs and clarify multiple superconducting (SC) phases in Sr$_2$RuO$_4$. Based on the analysis of the three-orbital Hubbard model with atomic LS coupling, we show some selection rules…
We report bulk ultrasound measurements up to 80 T and down to 0.5 K of the field re-entrant superconducting phase of the unconventional superconductor UTe$_2$. Clear bulk signatures of superconductivity are observed in the longitudinal…
A spatially modulated superconducting state, known as pair density wave (PDW), is a tantalizing state of matter with unique properties. Recent scanning tunneling microscopy (STM) studies revealed that spin-triplet superconductor UTe$_2$…
Higher-order topological superfluids have gapped bulk and symmetry-protected Majorana zero modes with various localizations. Motivated by recent advances, we present a proposal for synthesizing multi-order topological superfluids that…
Majority of the A$_2$B$_3$ type chalcogenide systems with strong spin-orbit coupling, like Bi$_2$Se$_3$, Bi$_2$Te$_3$ and Sb$_2$Te$_3$ etc., are topological insulators. One important exception is Sb$_2$Se$_3$, where a topological…
Recently, a superconducting (SC) transition from low-field (LF) to high-field (HF) SC states was reported in CeRh$_2$As$_2$, indicating the existence of multiple SC states. It has been theoretically noted that the existence of two Ce sites…
A spin supersolid is characterized by the simultaneous breaking of lattice translation and continuous spin rotation symmetries. In this work, we study a spin-1 model with $U(2)\cong SU(2)\times U(1)/Z_2$ symmetry on the triangular lattice,…
Topological superconductivity is central to a variety of novel phenomena involving the interplay between topologically ordered phases and broken-symmetry states. The key ingredient is an unconventional order parameter, with an orbital…
The recent measurement of the de Haas-van Alphen effect in the spin-triplet superconductor UTe2 [D. Aoki et al., J. Phys. Soc. Jpn. 91, 083704 (2022)] supports cylindrical electron and hole Fermi surfaces, which implies that UTe2 is trivial…
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…