Indium-contacted van der Waals gap tunneling spectroscopy for van der Waals layered materials.
Sci Rep
; 11(1): 17790, 2021 Sep 07.
Article
em En
| MEDLINE
| ID: mdl-34493752
ABSTRACT
The electrical phase transition in van der Waals (vdW) layered materials such as transition-metal dichalcogenides and Bi2Sr2CaCu2O8+x (Bi-2212) high-temperature superconductor has been explored using various techniques, including scanning tunneling and photoemission spectroscopies, and measurements of electrical resistance as a function of temperature. In this study, we develop one useful method to elucidate the electrical phases in vdW layered materials indium (In)-contacted vdW tunneling spectroscopy for 1T-TaS2, Bi-2212 and 2H-MoS2. We utilized the vdW gap formed at an In/vdW material interface as a tunnel barrier for tunneling spectroscopy. For strongly correlated electron systems such as 1T-TaS2 and Bi-2212, pronounced gap features corresponding to the Mott and superconducting gaps were respectively observed at T = 4 K. We observed a gate dependence of the amplitude of the superconducting gap, which has potential applications in a gate-tunable superconducting device with a SiO2/Si substrate. For In/10 nm-thick 2H-MoS2 devices, differential conductance shoulders at bias voltages of approximately ± 0.45 V were observed, which were attributed to the semiconducting gap. These results show that In-contacted vdW gap tunneling spectroscopy in a fashion of field-effect transistor provides feasible and reliable ways to investigate electronic structures of vdW materials.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Sci Rep
Ano de publicação:
2021
Tipo de documento:
Article