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Laser induced semiconductor-metal transition in a Quantum Well
P Nithiananthi1, C Rajamohan, K Jayakumar
1Department of Physics, Gandhigram Rural University, Gandhigram, 624302, Tamilnadu, India.
Journal of Nanoscience and Nanotechnology
|November 26, 2009
Summary
Investigating semiconductor-metal transitions in Al(x)Ga(1-x)As/GaAs quantum wells, this study shows laser fields can control donor diamagnetic susceptibility. A critical concentration, tunable by laser amplitude, signals this transition.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Quasi-two dimensional systems like Al(x)Ga(1-x)As/GaAs quantum wells exhibit unique electronic properties.
- Semiconductor-metal transitions are crucial phenomena with applications in advanced electronics.
- Donor impurities significantly influence the electronic behavior of semiconductor systems.
Purpose of the Study:
- To investigate the possibility of inducing a semiconductor-metal transition in Al(x)Ga(1-x)As/GaAs quantum wells.
- To explore the role of intense laser fields in controlling this transition.
- To analyze the behavior of donor diamagnetic susceptibility near the transition point.
Main Methods:
- Utilizing a finite barrier model for the quantum well system.
- Employing the variational principle to study the system's properties.
- Analyzing the abrupt changes in diamagnetic susceptibility of donors.
Main Results:
- An abrupt change in donor diamagnetic susceptibility was observed, indicating a semiconductor-metal transition.
- The transition is controllable by the amplitude of the applied laser field.
- A critical concentration of donors was identified as the threshold for this transition.
Conclusions:
- Intense laser fields can effectively induce and control semiconductor-metal transitions in Al(x)Ga(1-x)As/GaAs quantum wells.
- Donor diamagnetic susceptibility serves as a sensitive indicator of this transition.
- The finite barrier model and variational principle provide a robust framework for understanding these phenomena.
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