1. Silicon photonics vs. Traditional semiconductor chips: Scientists from the US and Europe have fabricated the first miniaturised lasers directly on silicon wafers.
o Applications: Data centres, sensors, and quantum computing.
o Photon advantages: Faster data transfer, higher capacity, and lower energy loss.
o Photonic Chip Components: Source (electrons/photons) → Waveguides (photon paths) → Modulators (encode/decode data) → Photodetectors (light to electricity).
o Laser principle: Based on stimulated emission, creating a coherent light beam.
o Silicon drawback: Has an indirect bandgap, poor for light emission.
o Common materials: Gallium arsenide (direct bandgap) enables efficient light emission.
o Semiconductors are materials that exhibit a conductivity level between conductors and insulators. They can be pure elements such as silicon or compounds like gallium arsenide.
Significance: Semiconductor chips serve as the fundamental building blocks and the "heart and brain" of modern electronics and information and communication technology (ICT) products