Observation of a subharmonic gap singularity in interlayer tunneling characteristics of Bi2Sr2CaCu2O8+d

Vestigial Van Hove singularity and higher-temperature superconducting phase induced by perpendicular uniaxial pressures in quasi-two-dimensional superconductors

We examine quasi-two-dimensional superconductors near half-filling under uniaxial pressures perpendicular to conductive layers (hereafter called perpendicular pressures). It is a natural conjecture that the perpendicular pressure decreases Tc because it increases the interlayer electron hopping energy t_z, which weakens the logarithmic enhancement in the density of states due to the two-dimensional Van Hove singularity. It is shown that, contrary to this conjecture, the perpendicular pressure can significantly enhance Tc in systems off half-filling before it decreases Tc, and the strength of t…

Observation of superconducting current in a mesa-heterostructure with an interlayer of the strontium iridate film with strong spin-orbit interaction

The superconducting current has been observed in mesa-heterostructures Nb/Au/Sr2IrO4/YBa2Cu3Ox with Sr2IrO4 interlayer thickness d=5 and 7 nm and in-plane sizes L=10-50 mcm. A strontium iridate, Sr2IrO4, is known as a canted antiferromagnetic insulator at low temperatures and characterized also by the strong spin-orbit interaction due to the impact of the IrO2 plane. The superconducting critical current density jC =0.3 A/cm^2 for the case d=7 nm was observed at T=4.2K. The temperature dependences of the superconducting critical current IC(T) and the voltage position on the I-V curve of the gap…

双层铜基超导体的间隙结构与相图：从微观视角

Gap structure and phase diagram of twisted bilayer cuprates from a microscopic perspective

本文通过紧束缚模型研究双层铜基超导体的间隙结构与相图，揭示了时间反演对称性破缺态与Van Hove奇点的关系，并探讨了不同隧穿强度下的约瑟夫森临界电流特性。

Transport in superconductor--normal metal--superconductor tunneling structures: Spinful p-wave and spin-orbit-coupled topological wires

We theoretically study transport properties of voltage-biased one-dimensional superconductor--normal metal--superconductor tunnel junctions with arbitrary junction transparency where the superconductors can have trivial or nontrivial topology. Motivated by recent experimental efforts on Majorana properties of superconductor-semiconductor hybrid systems, we consider two explicit models for topological superconductors: (i) spinful p-wave, and (ii) spin-split spin-orbit-coupled s-wave. We provide a comprehensive analysis of the zero-temperature dc current $I$ and differential conductance $dI/dV$ …

常压下具有最高 $T_c$ 的 HgBa$_2$Ca$_2$Cu$_3$O$_{8+δ}$ 中前所未有的大能隙

Unprecedentedly large gap in HgBa$_2$Ca$_2$Cu$_3$O$_{8+δ}$ with the highest $T_c$ at ambient pressure

通过对 $T_c=134$ K 的 Hg-1223 单晶进行 STS 测量，研究发现两组超导能隙及赝能隙和强粒子-空穴不对称，并用层间耦合三层模型加以解释。