Comprehensive review on topological superconducting materials and interfaces

Abstract

Superconductivity in topological materials has drawn a significant interest of the scientific community as these materials provide a hint of existence of Majorana fermions conceived from the quantized thermal conductivity, a zero-biased conduction peak and the anomalous Josephson effect. In this review, we make a systematic study of recent advances in the field of topological superconductivity. The article comprises of both bulk systems as well as heterostructures. A brief description of Majorana fermions and their relationship with topological superconductors and heterostructures is also carried out. Also, this review consists of details of key experimental techniques to characterize candidates of topological superconductivity. Moreover, we summarize the potential material candidate that may demonstrate topological superconductivity. We also consider some intrinsic odd-parity superconductors, non-centrosymmetric, centrosymmetric superconductors, doped topological insulators, doped topological crystalline insulators and some other materials that are expected to show superconductivity along with topological non-trivial states in bulk from. The effect of pressure, emergence of superconductivity in topological materials and Muon Spin Rotation (SR) studies are also summarized in this article.

Nearly three-dimensional Dirac fermions in an organic crystalline material unveiled by electron spin resonance

“…where g 0 is the common amplitude of g x (y) and g y (y). Eqn (4) indicates that an ideal 2D (fourfold rotation symmetry) spin system exhibits a constant g-value when they are rotated around the symmetry axis, as was effectively observed in the ESR spectra in the ab plane (Fig. S2, ESI †).…”

“…Recently, a quantum state of matter called topological material has garnered considerable attention from a wide range of materials scientists. [1][2][3][4][5][6][7] There are many types of topological materials known to date. All of their unique physical properties originate from Dirac fermions (DFs) located around the Fermi levels and governing the electrical, magnetic, and optical properties, instead of the standard fermions (SFs) of electrons or holes in common materials.…”

Two-dimensional superconductors with intrinsic p-wave pairing or nontrivial band topology

“…Motivated by the promising technique application of Majorana fermion, tremendous efforts have been devoted to realizing TSC in realistic material systems [2,11,12,[34][35][36][37][38][39]. Topological property of a superconductor is characterized by the phase winding of order parameter around its Fermi surface [2,11], which suggests odd-parity spin-triplet superconductor is a promising ground for realizing TSC [31].…”

“…For reciprocal-space proximity or band proximity effect-induced TSC, typical examples are doped 3D topological insulators [51][52][53][54] and iron-based superconductors [55][56][57][58][59][60][61][62][63][64], where superconductivity arising from the bulk bands is proximity coupled to the topological surface states, mimicking effective 2D chiral p-wave superconductors. Intrinsic TSC means that superconductivity and nontrivial topology arise from the same electronic states of the same material [12,37,39]. There are increasing numbers of materials showing signatures of intrinsic topological superconductivity, such as Sr 2 RuO 4 [65], UTe 2 [66], Pb 3 Bi [67].…”

Ultrahigh Carrier Mobility in Cd3As2 Nanowires

“…The unique band structure of DSMs can also give rise to many other topological phases such as topological superconductors. [ 26 ] To make things more advantageous for devices, its Fermi surface is also very close to the DPs. nanowires have been shown to exhibit universal conductance fluctuations, [ 13,22,27,28 ] phase‐shifted Aharonov–Bohm (AB) oscillations, [ 28 ] as well as suppressed Klein tunneling in quantum dot‐hosting nanowires.…”