Bandgap theory

Bandgap theory describes the energy difference between the highest occupied energy level (valence band) and the lowest unoccupied level (conduction band) in a material. In semiconductors, this bandgap allows for controlled conductivity: electrons can gain energy and jump from the valence band to the conduction band, conducting electricity. Materials with a large bandgap (like insulators) do not conduct well, while those with a small bandgap (like metals) conduct easily. Understanding bandgaps is crucial for designing electronic components, such as transistors and solar cells, affecting how they operate and their efficiency.