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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Probing electron-electron interaction in quantum Hall systems with scanning tunneling spectroscopy
S Becker1, C Karrasch, T Mashoff
1II. Physikalisches Institut B and JARA-FIT, RWTH Aachen University, 52074 Aachen, Germany.
Physical Review Letters
|May 17, 2011
Summary
We observed electron-electron interactions in a quantum Hall system using scanning tunneling spectroscopy. Our findings reveal a Coulomb gap, demonstrating interaction effects at nanoscale resolutions.
Area of Science:
- Condensed matter physics
- Quantum phenomena
Background:
- Two-dimensional electron systems (2DES) are crucial for understanding quantum phenomena.
- Investigating electron-electron interactions in the quantum Hall regime provides insights into correlated electron behavior.
Purpose of the Study:
- To probe electron-electron interaction effects in a Cs-induced 2DES on p-type InSb(110) within the quantum Hall regime.
- To investigate the spatial and local density of states and spin splitting.
Main Methods:
- Low-temperature scanning tunneling spectroscopy (LT-STM).
- Application to a Cs-induced two-dimensional electron system (2DES) on p-type InSb(110).
Main Results:
- Observed exchange enhancement of spin splitting, quantitatively matching theoretical calculations.
- Detected a characteristic Coulomb gap at the Fermi level in both spatially averaged and local density of states.
- Demonstrated probing of electron-electron interactions at resolutions below relevant length scales.
Conclusions:
- Electron-electron interactions significantly influence the quantum Hall regime in 2DES.
- LT-STM is a powerful technique for resolving nanoscale interaction effects.
- The observed Coulomb gap provides direct evidence of electron correlation effects.
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