Temperature derivative of the chemical potential and its magnetooscillations in two-dimensional system
Y. Tupikov+×, A. Yu. Kuntsevich+*, V. M. Pudalov+*, I. S. Burmistrov*°
+Lebedev Physical Institute of the RAS, 119991 Moscow, Russia
*Moscow Institute of Physics and Technology, 141700 Moscow, Russia
×Department of Physics, Pennsylvania State University, University Park, PA 16802, USA
°Landau Institute for Theoretical Physics, 119334 Moscow, Russia
Abstract
We report first thermodynamic measurements of the temperature derivative of
chemical potential () in two-dimensional (2D) electron
systems. In order to test the technique we have chosen Schottky gated
GaAs/AlGaAs heterojunctions and detected experimentally in this 2D system
quantum magnetooscillations of . We also present a
Lifshits-Kosevitch type theory for the
magnetooscillations in 2D systems and compare the theory with experimental data.
The magnetic field dependence of the value appears to
be sensitive to the density of states shape of Landau levels. The data in low
magnetic field domain demonstrate brilliant agreement with theory for
non-interacting Fermi gas with Lorentzian Landau level shape.