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Schrödinger equation

Simple examples

Band structure

Electron waves in the

semiconductor

Band structure describes the dispersion relation between energy and wave number for ALLOWED wave states in the semiconductor.

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In classical physics, all things are either particles or waves.

Particles: atoms, electrons, cars, boats, houses, people…..

Waves: light, heat, water motion, radio signals, ….

Particles and waves are distinct objects, and things just don’t have the properties of both.

However, if we look a little closer, these facts and interpretations start to blur…

LIGHT AS A WAVE INTERFERENCE and DIFFRACTION

COHERENT LIGHT SOURCE

Light is diffracted by the

aperatures

Just as for X-ray diffraction, the light has constructive and destructive interference where the diffracted beams come together

CLASSICALLY LIGHT IS TREATED AS AN ELECTROMAGNETIC WAVE IN WHICH ELECTRIC AND MAGNETIC FIELD COMPONENTS OSCILLATE IN PHASE WITH EACH OTHER

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Quantum mechanics around 1900 led to a connection between energy and frequency, which is known as the Planck relation:

sJhhE

⋅×

=−341063.6~ν

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Transmission Coefficient T: where Reflection Cofficient R: R= 1-T

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Quantized Electron Energy:

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LASER: Light Amplification by Stimulated Emission of Radiaton

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