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Measurements of the density-dependent many-body electron mass in 2D GaAs/AlGaAs Heterostructures

Y. -W. Tan·J. Zhu·H. L. Stormer·L. N. Pfeiffer·K. W. Baldwin·K. W. West
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Abstract

We determine the density-dependent electron mass, m*, in two-dimensional (2D) electron systems of GaAs/AlGaAs heterostructures by performing detailed low-temperature Shubnikov deHaas measurements. Using very high quality transistors with tunable electron densities we measure m* in single, high mobility specimens over a wide range of r_s (6 to 0.8). Toward low-densities we observe a rapid increase of m* by as much as 40%. For 2>r_s>0.8 the mass values fall ~10% below the band mass of GaAs. Numerical calculations are in qualitative agreement with our data but differ considerably in detail.

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Y. -W. Tan, J. Zhu, H. L. Stormer, L. N. Pfeiffer, K. W. Baldwin, K. W. West. 2004-12-10. Measurements of the density-dependent many-body electron mass in 2D GaAs/AlGaAs Heterostructures. https://doi.org/10.1103/physrevlett.94.016405

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