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Question 1

What is quantum electronics?

Answer 1

The field of Quantum Electronics describes propagation of light and its interaction with matter. Emphasis is on linear pulse and beam propagation in dispersive media, optical anisotropic materials, and waveguides and lasers.

Question 2

Invention of LASER

Answer 2

• Brightest
• most efficient light source
• coherent (can interfere)
• First laser emission obtained by Theodore Maiman on 16 May 1960.

Question 3

Fabrication of low loss optical fibres

Answer 3

In 1965, Kao & Hockham promoted the idea to reduce attenuation in optical fibres below 20 dB/km. Achieved in 1970 by Corning Glass Works researchers with 17 dB/km attenuation by doping silica glass with titanium.

Question 4

LED vs Photodiode

Answer 4

• LED, laser diode: Light Emitting Elements converting electric current into light.
• Photodiode, phototransistor, camera: Light Receiving Elements converting light into electric current.

Question 5

Maxwell’s equations in free space

Add actual equations!

Answer 5

• Describe how electric and magnetic fields propagate.
• ε₀ (electric permittivity) and μ₀ (magnetic permeability) are constants in vacuum.
• E (electric field) and B (magnetic field) are vectors.

Question 6

Electromagnetic theory of light

Answer 6

Light is an oscillating electric and magnetic field, which are coupled and propagate as an electromagnetic wave.

Question 7

Photon energy equation

Answer 7

E = hc/λ, where h is Planck’s constant (6.6261 x 10^-34 J·s) and c is the speed of light (2.9979 x 10⁸ m/s).

Question 8

1 nm in angstrom

Answer 8

10 Å

Question 9

Maxwell’s equations in a medium

Answer 9

Account for the influence of materials on electromagnetic fields. More complex than in free space due to the material’s atomic structure.

add actual equation!

Question 10

Key approximation: microscopic to macroscopic

Answer 10

Approximations used to model large scale materials’ effects on electromagnetic waves, from atomic-scale properties to continuum-scale descriptions.

Question 11

LASER acronym

duplicate

Answer 11

Light Amplification by Stimulated Emission of Radiation.

Question 12

Maxwell’s equations: historical significance

not relevant

Answer 12

Published by James Clerk Maxwell in 1873, they unified the theories of light and electromagnetism. Experimentally proven by Heinrich Hertz in the 1890s.

Question 13

Electromagnetic spectrum

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Answer 13

• Range of all types of EM radiation.
• Light energy E is inversely proportional to wavelength λ.