Quantum ballistic transport in in-plane-gate transistors showing onset of a novel ferromagnetic phase transition

✍ Scribed by Ralf D. Tscheuschner; Andreas D. Wieck

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 148 KB
• Volume: 20
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.1996.0123

✦ Synopsis

We study one-dimensional transport in focused-ion-beam written in-plane-gate transistors on III-V heterostructures at moderately low temperatures at zero bias without any external magnetic field applied. In accordance with a recent proposal of A. Gold and L. Calmels, 'Valley-and spin-occupancy instability in the quasi-one-dimensional gas', Phil. Mag. Lett. 74, 33 (1996) and earlier experimental data, we observe plateaux in the source-drain conductivity considered as a function of the gate voltage, not only at multiples of 2e 2 / h but also clearly at e 2 / h, just before the channel closes to zero conductivity. This may be interpreted as a many-electron effect, namely as a novel ballistic ferromagnetic ground state evading standard descriptions and theorems.