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Microwave zero-resistance states in a bilayer electron system
S Wiedmann1, G M Gusev, O E Raichev
1LNCMI-CNRS, UPR 3228, BP 166, 38042 Grenoble Cedex 9, France.
Physical Review Letters
|September 28, 2010
Summary
High-mobility electron systems exhibit zero-resistance states (ZRS) under microwave irradiation, even with intersubband scattering. This phenomenon, observed in GaAs quantum wells, correlates with conditions for absolute negative resistivity.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Semiconductor Nanostructures
Background:
- High-mobility electron systems are crucial for advanced electronic devices.
- Quantum wells confine electrons, leading to unique quantum phenomena.
- Microwave irradiation can alter electron behavior in confined systems.
Purpose of the Study:
- Investigate magnetotransport in a high-mobility electron bilayer.
- Explore the emergence of zero-resistance states (ZRS) under microwave irradiation.
- Analyze the influence of intersubband scattering on ZRS.
Main Methods:
- Performed magnetotransport measurements on a GaAs quantum well system.
- Applied continuous microwave irradiation with varying frequency, power, and temperature.
- Compared experimental findings with theoretical models of absolute negative resistivity.
Main Results:
- Observed vanishing dissipative resistance under microwave irradiation.
- Detected profound zero-resistance states (ZRS) despite intersubband scattering.
- Found a correlation between ZRS appearance and conditions for absolute negative resistivity.
Conclusions:
- Microwave irradiation induces novel transport phenomena in electron bilayer systems.
- Zero-resistance states are achievable even with competing scattering mechanisms.
- The study provides experimental evidence supporting theories of absolute negative resistivity.
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