Semiconductor Physics in Magnetic Fields

Tadashi Takamasu, Kanji Takehana, Yasutaka Imanaka
Nano Physics Group

Mission With the application of the strong magnetic fields, electrons in materials show cyclotron motion. As a result, the wave function of electrons is confined to the small area of the order of several nanometers. Such confined electrons correlate strongly with each other and show many interesting phenomena such as quantum Hall effect. Our research purpose is to find new phenomena related to the strongly correlated electrons and to clarify the physical origin of such phenomena. We are studying mainly semiconductors and its low-dimensional structures in terms of spectroscopy in visible-, infrared-light and millimeter waves. Technical Characteristic Coupled system of quantum dots and 2-d electrons We have succeeded in observing hysteretic curves in the gate voltage dependence of magneto-resistance with the system of quantum dots and 2d electrons system, which indicate spin related electron scattering between quantum dots and 2d electrons. Developments of measurements system in strong magnetic fields In addition to the semiconductor physics, we have developed various methods such as high-field-atomic force microscope, microscopic spectroscopy and tera-hertz spectroscopy systems.