Seminarium Oddziału Niskich Temperatur i Nadprzewodnictwa
sala 6, bud. 2
Pure 100% Ge 20 nm Quantum Wells with Extremely High Hole Mobility of 2D Hole Gas
Prof. O. A. Mironov
NanoSilicon Group, Department of Physics, University of Warwick, Coventry, UK
O.A. Mironov, A. Dobbie, A.H.A. Hassan, R.J.H. Morris,S. Gabani, E. Cizmar, I.B. Berkutov,V.V. Andrievskii and D.R. Leadley
We present magneto-transport properties of a Two Dimensional Hole Gas (2DHG) formed within fully strained (0.64%) Germanium (sGe) quantum wells grown on Si0.2Ge0.8/Si (100) substrates by RP-CVD method. Comparison is made between heterostructures that are modulation doped in both normal and inverted configurations. Using Shubnikov de Haas oscillations at temperatures down to 90 mK (inverted structure) and to 1.5 K (normal structure), an extremely high hole mobility (0.51-1.34) ×106 cm2/Vs has been observed, along with the lowest value of effective mass (0.063-0.070) m0 to date. The 2DHG is confirmed to be in a pure Ge channel, with low background impurity scattering that improves the 2DHG transport.
