Enhanced Superconductivity in Monolayer T_d-MoTe₂

Abstract

Crystalline two-dimensional (2D) superconductors (SCs) with low carrier density are an exciting new class of materials in which electrostatic gating can tune superconductivity, electronic interactions play a prominent role, and electrical transport properties may directly reflect the topology of the Fermi surface. Here, we report the dramatic enhancement of superconductivity with decreasing thickness in semimetallic T d-MoTe2, with critical temperature (T c) increasing up to 7.6 K for monolayers, a 60-fold increase with respect to the bulk T c. We show that monolayers possess a similar electronic structure and density of states (DOS) as the bulk, implying that electronic interactions play a strong role in the enhanced superconductivity. Reflecting the low carrier density, the critical temperature, magnetic field, and current density are all tunable by an applied gate voltage. The response to high in-plane magnetic fields is distinct from that of other 2D SCs and reflects the canted spin texture of the electron pockets.

Superconductivity enhancement in phase-engineered molybdenum carbide/disulfide vertical heterostructures

“…This has been assumed to be evidence for the so-called Ising-paired state, whose spin-singlet Cooper pairing would occur among carriers at the K and K′ valleys having opposite spins. Moreover, in 2D MoTe 2, a type-II Weyl semimetal, T C can be enhanced either through a sulfur doping driven phase transition (from the monoclinic 1T′ to the orthorhombic T d phase) (8), which is claimed to enhance the electron-phonon coupling (9), or through exfoliation down to the monolayer limit (10). Two-dimensional superconductivity is now emerging as a scientific frontier addressing a number of unanswered questions, such as the disparate evolution of the superconducting transition temperature as a function of the number of layers and different stackings within different compounds (6,7).…”

Quantifying the Charge Carrier Interaction in Metallic Twisted Bilayer Graphene Superlattices

“…The proposed approach potentially can be applicable for a wide range of materials, including 2D superconductors [ 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 ] and superhydrides [ 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 ].…”

Intercalated phases of transition metal dichalcogenides

“…Intrinsic SC can be induced in monolayer WTe 2 by electrostatic gating at 0.82 K 120,121 . Bulk and monolayer MoTe 2 has intrinsic SC at 0.25 and 8 K, respectively 122,123 . K‐intercalated WTe 2 synthetsized by liquid ammonia method shows improved superconducting transition temperature at 2.6 K 110 .…”