Related papers: Freestanding single-crystal superconducting electr…
We will summarize here some of our measurements of the superconducting fluctuations effects on the in-plane electrical resistivity (the so-called in-plane paraconductivity) in La_{2-x}Sr_xCuO_4 thin films with different Sr content. Our…
Van der Waals (vdW) superconductors - atomically thin crystalline materials that can be stacked into more complex heterostructures - have opened a promising avenue for superconducting electronics thanks to their properties that are…
In this study, a possible non-quasiparticle glue for superconductivity of both conventional and unconventional superconductors is explored in a pure electron picture. It is shown clearly that the moving electrons due to the electromagnetic…
The discovery of infinite-layer nickelate superconductors has spurred enormous interest. While the Ni$^{1+}$ cations possess nominally the same 3$d^9$ configuration as Cu$^{2+}$ in cuprates, the electronic structure variances remain…
Extensive muon spin relaxation measurements have been performed to determine the magnetic field penetration depth in high-Tc cuprate superconductors with simple hole doping, Zn-doping, overdoping, and formation of static SDW nano islands.…
Understanding the doping evolution from a Mott insulator to a superconductor probably holds the key for resolving the mystery of unconventional superconductivity in copper oxides. To elucidate the evolution of the electronic state starting…
We present a comprehensive study of the crystal structure of the thin-film, ferromagnetic topological insulator (Bi, Sb)$_{2-x}$V$_x$Te$_3$. The dissipationless quantum anomalous Hall edge states it manifests are of particular interest for…
We investigate the spatial and doping evolutions of the superconducting properties of tri-layer cuprate Bi2Sr2Ca2Cu3O10+x by using scanning tunneling microscopy and spectroscopy. Both the superconducting coherence peak and gap size exhibit…
The extreme variability of observables across the phase diagram of the cuprate high temperature superconductors has remained a profound mystery, with no convincing explanation of the superconducting dome. While much attention has been paid…
The electron-doped cuprates were studied by electronic Raman spectroscopy across the entire region of the superconducting (SC) phase diagram. We determined that the magnitude of the SC order parameter varies between 4.6 and 3.5 k_BT_c,…
We measured the magnetoresistance as a function of temperature down to 20mK and magnetic field for a set of underdoped PrCeCuO (x=0.12) thin films with controlled oxygen content. This allows us to access the edge of the superconducting dome…
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…
Superconductivity is inevitably suppressed in reduced dimensionality. Questions of how thin superconducting wires or films can be before they lose their superconducting properties have important technological ramifications and go to the…
Based on a Fermi liquid model, we present several results on the normal state of the optimally doped and overdoped cuprate superconductors. Our main result is an analytic demonstration, backed by self-consistent numerical calculations, of…
In order to investigate the low-energy antiferromagnetic Cu-spin correlation and its relation to the superconductivity, we have performed muon spin relaxation (muSR) measurements using single crystals of the electron-doped high-Tc cuprate…
Particle-wave duality suggests we think of electrons as waves stretched across a sample, with wavevector k proportional to their momentum. Their arrangement in "k-space," and in particular the shape of the Fermi surface, where the highest…
There is an ongoing debate about the relative importance of structural change versus doping charge carriers on the mechanism of superconductivity in Fe-based materials. Elucidating this issue is a major challenge since it would require a…
Topological quantum materials that show strongly correlated electrons as well as topological order, for which spin-orbit coupling is a key ingredient, exhibit novel states of matter. One such example is the family of pyrochlore iridates,…
We have investigated properties of superconducting titanium nitride (TiN) films that were sputtered over a large range of RF-induced DC bias voltage applied to the substrate. Films grown with the largest bias voltages contained cubic TiN…
We study the effects of a superconducting condensate on holographic Fermi surfaces. With a suitable coupling between the fermion and the condensate, there are stable quasiparticles with a gap. We find some similarities with the…