Double photoemission from Ag and Pd surfaces: Energy relations

Abstract

We have investigated the electron pair emission due to single-photon absorption from Ag(100) and Pd(100) surfaces. We are interested in the energy spectra of pairs in particular near the energy cutoff. The sum energy spectra of Ag display a distinctive photon energy dependence. We also observe some fine structure. Near the high-energy cutoff the coincidence rate is too low to determine the energy position of the cutoff. Nevertheless we observe a finite signal if two 5sp electrons near the Fermi level are emitted. For Pd(100) we find sum energy spectra without fine structure and the cutoff region is approached linearly. Within the experimental accuracy the minimum energy to liberate two electrons is twice the work function.

Supercurrent diode effect and finite momentum superconductivity

“…The supercurrent diode effect predicted in this work, including nonreciprocal critical current and polaritydependent in-plane critical field, may be observed in polar SrTiO 3 films [33] and artificially engineered heavy fermion superlattices of YbCoIn 5 -YbRhIn 5 -CeCoIn 5 [25], where the layer stacking breaks inversion symmetry. In both cases, an upturn of in-plane critical field has been observed and attributed to the Rashba spin splitting.…”

Topological metals and finite-momentum superconductors

“…The interplay between spinorbit and Zeeman splitting has interesting consequences for superconductivity, as shown in many previous works [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Recent discovery of superconductivity in a variety of two-dimensional spin-orbit-coupled materials, including transition metal dichalcogenides [19] and strontium titanate films [20], adds new venues for further investigation of this important problem.…”