Electron Transport Properties in a GaAs/AlGaAs Quantum Wire Grown on V-Grooved GaAs Substrate by Metalorganic Vapor Phase Epitaxy

• Published in: Japanese Journal of Applied Physics 2003, Vol.42 (Part 1, No. 4B), p.2399-2403
• Main Authors: Hahn, Cheol-Koo, Sugaya, Takeyoshi, Jang, Kee-Youn, Wang, Xue-Lun, Ogura, Mutsuo
• Format: Article
• Language: English
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.42.2399

A series of nonlinear conductance phenomena is investigated in the GaAs V-grooved quantum wire (QWR) FETs prepared by the flow-rate modulated epitaxy technique. These are attributed to Coulomb blockade at a subthreshold gate bias, universal conductance steps near the threshold, real space transfer under a forward gate bias and a large source-drain bias condition. Weak carrier coupling between sidewall quantum wells and QWR is responsible for the small step height of the measured universal conductance (Gm < < G0=2e2/h). Shubnikov de Haas oscillation measurements revealed that sidewall quantum wells in the V-groove quantum wire act as additional current paths and are switched or mixed with QWR depending on the gate bias conditions and device geometry. The gate-bias-dependent current path switching is responsible for the large current steps and negative differential resistance in the drain current (IDS)-gate bias and IDS-drain bias relationships, resp. 13 refs.