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Updated: Jul 24, 2026
08:53
Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
Laterally modulated 2D electron system in the extreme quantum limit.
S Melinte1, Mona Berciu, Chenggang Zhou
1Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA.
Physical Review Letters
|February 3, 2004
Summary
We observed complex resistivity fluctuations in a two-dimensional electron system (2DES) under a modulated surface superlattice. Disorder
Area of Science:
- Condensed matter physics
- Materials science
Background:
- Two-dimensional electron systems (2DES) are crucial for understanding quantum phenomena.
- Surface superlattices introduce periodic potential modulations affecting electron behavior.
Purpose of the Study:
- To investigate magnetotransport properties of a 2DES with a surface superlattice gate.
- To analyze the influence of periodic modulation on resistivity fluctuations.
Main Methods:
- Fabrication of a 2DES with a surface superlattice gate structure.
- Measurement of magnetotransport, specifically diagonal resistivity, at low Landau level fillings.
- Theoretical modeling considering disorder and periodic modulation effects.
Main Results:
- Observed a rich pattern of diagonal resistivity fluctuations in the 2DES.
- Disorder effects were found to dominate over the periodic modulation.
- Fluctuations occurred at low Landau level fillings (nu).
Conclusions:
- Theoretical arguments qualitatively explain the observed magnetotransport data.
- The interplay between strong disorder and weak periodic modulation governs the system's behavior.
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