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Electron emission from a semiconductor quantum ring under normally incident radiation
Susmita Sen1, N R Das, A N Chakravarti
1Birla Institute of Technology, 56 B T Road, Kolkata 700 050, India.
Summary
Investigating electron emission from quantum rings reveals that current density rises with photon energy. Reducing ring dimensions enhances this current, with threshold energy offering insights into semiconductor parameters.
Area of Science:
- Semiconductor Physics
- Quantum Mechanics
- Materials Science
Background:
- Quantum rings are crucial in nanoscale electronics.
- Understanding photoemission in semiconductors is key for device applications.
- Degenerate wide-gap semiconductors exhibit unique electronic properties.
Purpose of the Study:
- To analyze electron emission current density in toroidal quantum rings under irradiation.
- To explore the influence of incident photon energy and ring dimensions on photoemission.
- To investigate the behavior of threshold energy for photoemission.
Main Methods:
- Computational analysis of electron emission.
- Modeling of toroidal quantum rings made of strongly degenerate wide-gap semiconductors.
- Examination of current density and threshold energy as functions of physical parameters.
Main Results:
- Current density exhibits a step-like increase with incident photon energy.
- Reducing the ring's dimensions leads to increased current density.
- Photoemission threshold energy shows an oscillatory dependence on the cross-sectional radius.
Conclusions:
- The findings provide a method for tuning photoemission properties.
- Threshold energy's dependence on cross-sectional radius can monitor ring parameters.
- Ring circumference does not affect the photoemission threshold energy.
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