Topological superconducting states in monolayerFeSe/SrTiO3

Abstract

The monolayer FeSe with a thickness of one unit cell grown on a single-crystal SrTiO 3 substrate (FeSe/STO) exhibits striking high-temperature superconductivity with transition temperature T c over 65 K reported by recent experimental measurements. In this work, through analyzing the distinctive electronic structure, and providing systematic classification of the pairing symmetry, we find that both sand p-wave pairing with odd parity give rise to topological superconducting states in monolayer FeSe, and the exotic properties of s-wave topological superconducting states have close relations with the unique nonsymmorphic lattice structure which induces the orbital-momentum locking. Our results indicate that the monolayer FeSe could be in the topological nontrivial s-wave superconducting states if the relevant effective pairing interactions are dominant in comparison with other candidates.

Topological quantum states of matter in iron-based superconductors: from concept to material realization

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Stable monolayer α-phase of CdTe: strain-dependent properties

“…These type of structures belong to the space group of P4/nmm. [56][57][58] Primitive cell is square and includes two Cd and two Te atoms. As seen in Table I, the lattice parameter of the monolayer α-CdTe is calculated to be 4.66Å, which is smaller than that of bulk zb-CdTe, and the thickness (vertical distance between uppermost and lowermost Te atoms) is found to be 3.55Å.…”

Topological edge states in a high-temperature superconductor FeSe/SrTiO3(001) film

“…Recently, the possible existence of topological phases in FeSe has drawn much attention [8][9][10] . In this work, we demonstrate both theoretical and experimental evidence for an antiferromagnetic (AFM) quantum spin Hall (QSH) state in FeSe.…”