MAGNETIZATION OF A BILAYER 2D ELECTRON GAS

摘要

We present torque-magnetometry measurements of a bilayer two-dimensional electron gas (2DEG) with an inter-well barrier thin enough to enable a strong coupling between the quantum wells. We observe magnetization steps related to symmetric-anti-symmetric (SAS) transitions. Increasing the in-plane magnetic field leads to a reduction of the SAS splitting. Surprisingly, the heights of the magnetization steps related to Landau-level transitions are reduced relative to those measured for single-layer 2DEGs, suggesting that an in-plane magnetization component plays a role. Finally, at total filling factor ν = 4, we observe an unidentified magnetization peak superposed upon the Landau-level step.