Conductance oscillations in a deformable quantum ring

✍ Scribed by S.H. Yang; A.S. Adourian; R.M. Westervelt; K.L. Campman; A.C. Gossard

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 568 KB
• Volume: 100
• Category: Article
• ISSN: 0038-1098
• DOI: 10.1016/s0038-1098(96)00499-1

✦ Synopsis

Low temperature magnetoconductance oscillation measurements are reported for a deformable quantum ring. The quantum ring is formed from a two-dimensional electron gas in a GaAs/Ale3Gaa,+s heterostructure via electrostatic gates: outside gates define the outer perimeter with two quantum point contacts and a separately contacted center gate forms a central hole with adjustable size. Three lithography layers, aligned to 50 nm precision, were required to achieve independent contact to the center gate. Series of magneto-oscillation power spectra for increasing size of the central hole show two sets of peaks: one at essentially constant magnetic frequency corresponding to the area enclosed by the outer circumference as for edge-state interference and one which shifts to lower frequency corresponding to the area of the electron ring.