Suspended two-dimensional electron gases for nanoelectromechanical applications

D. KAZAZIS; Y. JIN; R. GIRAUD; M. GRANADA; R. BRAIVE; U. GENNSER; T. ANTONI

Workshop; Réunion GDR 2426: Physique Quantique Mésoscopique; 2010

Nanoelectromechanical systems (NEMS) have recently attracted a lot of attention in the scientific community. Thanks to the technological advances in nanofabrication, the development of electromechanical devices in the nanoscale is a reality that enables the study of both their physics and of various interesting applications. We are investigating the possibilities of nanoelectromechanical devices based on III-V (AlGaAs/GaAs) heterostructures grown by molecular beam epitaxy (MBE). In particular, suspended two-dimensional electron gases (2DEGs) have been realized on membranes. As verified by low-temperature quantum Hall-effect (QHE) measurements, the suspended 2DEGs have mobilities and densities comparable to the case of the non-suspended ones. In addition, the resonant modes of the membranes have been measured by means of Michelson interferometry and compared with simulations. This provides supplemental evidence for the full suspension of the 2DEG. Given the overall good control of the fabrication process, the flexibility of MBE grown heterostructures, and the good quality of the above suspended 2DEGs, new paths open up for research in the field of NEMS, such as the quantum behavior of mesoscopic mechanical systems, motion sensors in the nanoscale and terahertz detectors and sources.