Optical control of the mobility of a MODFET with a layer of self-assembled quantum dots

摘要: Abstract We report an experimental study of GaAs/Al 0.33 Ga 0.67 As modulation doped field effect (MODFET) transistors, in which InAs layer self-assembled quantum dots is placed one the Al barrier layers close to two-dimensional electron gas (2DEG). find source–drain resistance bistable with two states controlled by illumination and applied gate bias. Brief induces a large, persistent drop resistance, can be recovered applying positive Magneto-transport measurements show that while causes only relatively small change 2DEG density, it greatly enhance its mobility. suggest this because mobility limited percolation electrons through rough electrostatic potential induced charged dots. Illumination reduces negative charge trapped dots, thus smoothing conduction band potential, produces large increase