In a high-mobility two-dimensional electron gas (2DEG) in a GaAs/Al${}_{0.3}$Ga${}_{0.7}$As quantum well we observe a strong magnetoresistance. In lowering the electron density, the magnetoresistance gets more pronounced and reaches values of more than 300$\%$. We observe that the huge magnetoresistance vanishes when increasing the temperature. An additional density-dependent factor is introduced to be able to fit the parabolic magnetoresistance to the electron-electron interaction correction.

• Received 30 November 2010

DOI:https://doi.org/10.1103/PhysRevB.83.113301