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Updated: Jun 25, 2025
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Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
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Hexagonal warping effects on Bloch oscillations in proximitized Rashba systems
1Department of Physics, Kohat University of Science and Technology, Kohat 26000, Khyber Pakhtunkhwa, Pakistan.
Summary
Bloch oscillations (BOs) in Rashba systems show unique behaviors influenced by hexagonal warping and band gaps. External fields induce dynamic phase transitions and negative differential conductivity, revealing novel electron dynamics.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Bloch oscillations (BOs) are fundamental quantum mechanical phenomena in crystals.
- Rashba systems exhibit spin-orbit coupling effects crucial for spintronics.
- Hexagonal warping and band gaps significantly alter electronic band structures.
Purpose of the Study:
- To investigate Bloch oscillations in Rashba systems with hexagonal warping and proximity-induced band gaps.
- To explore the influence of external electric and magnetic fields on these oscillations.
- To analyze the dynamic phase transitions and conductivity properties.
Main Methods:
- Theoretical analysis of electron dynamics in modified Rashba systems.
- Investigation of group and Berry velocity behavior.
- Study of responses to combined in-plane electric and transverse magnetic fields.
Main Results:
- Novel Bloch oscillations observed in group and Berry velocities, dependent on crystal momentum.
- Significant modification of BOs by hexagonal warping and band gap strength.
- External fields induce a dynamic phase transition between confined and de-confined states.
- Negative differential conductivity observed in the direct-current drift velocity.
Conclusions:
- Hexagonal warping and band gaps introduce unique characteristics to Bloch oscillations.
- External fields provide a means to control and visualize Bloch electron dynamics.
- The interplay of intrinsic properties and external fields leads to dynamic phase transitions and novel conductivity behaviors.
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