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arXiv · 2311.14355

Unveiling the pairing Symmetry of the superconducting Sn/Si(111) via angle-resolved THz pump spectroscopy

Mattia Iannetti·Tommaso Cea·Cesare Tresca·Lara Benfatto·Gianni Profeta
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Abstract

Doping tin surface epitaxially grown on silicon, Sn/Si(111), with boron atoms yields the appearance of a superconducting (SC) phase below $T_c\sim 4-5$K. Even though the pairing mechanism remains unknown, experimental evidence of chiral $d-$wave superconductivity has been recently reported, then ruling out a phonon-mediated pairing. Here we study theoretically the SC phase and symmetries of the doped Sn/Si(111) within a $t-J$ model. We analyze the photo-excitation of the system by intense THz pulses and show that the polarization dependence of the induced current can distinguish between different symmetries of the SC gap, thus providing a novel experimental mean to investigate the spectroscopic features of the Sn/Si(111) across the SC transition.

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Mattia Iannetti, Tommaso Cea, Cesare Tresca, Lara Benfatto, Gianni Profeta. 2023-11-24. Unveiling the pairing Symmetry of the superconducting Sn/Si(111) via angle-resolved THz pump spectroscopy. https://arxiv.org/abs/2311.14355

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