1. ECE 874: Physical Electronics
Prof. Virginia Ayres
Electrical & Computer Engineering
Michigan State University

2. Lecture 07, 20 Sep 12
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3. Chp. 02: 3 important examples of electron showing wavelike properties
Free electron
An electron between scattering events during transport in a semiconductor is often nearly free
Motivation: low heat transistors
Electron in an infinite potential well
Electron in a finite potential well
Pr. 2.7: Electrons in a triangular well = realistic
Motivation: these are all about Quantum well lasers:
Arai article:
Transitions between quantized energy levels DE = hc/l : what you see is light of precise wavelength l
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4. Approach: conservation of energy applied to wavelike electrons
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5. Approach: conservation of energy applied to wavelike electrons/particles:
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6. Approach: conservation of energy applied to wavelike electrons
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7. Approach: conservation of energy applied to wavelike electrons
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8. Approach: conservation of energy applied to wavelike electrons
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9. Example problem: what is the KE of a nearly free electron in GaAs, described by the traveling wave:
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10. Example problem: what is the KE of a nearly free electron in GaAs, described by the traveling wave:
Travelling wave moving R *
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13. Example problem: what is the total energy E of a nearly free electron in GaAs, described by the traveling wave:
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15. This is a particular example of a problem that has a time independent formulation, p 31-32.
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16. I’d ask: what do I need to get to this since I know it equals 1.
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18. 1. Free or nearly free electron/particle:
Find y(x,t)
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21. Already did these as example problems:
For a free particle, the energy is all kinetic.
The pot’l energy U(x,y,z) associated with its physical situation is 0.
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22. Dispersion diagram: E-k:
= hbark
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