Modern Engineering Materials Quiz

Metallic glasses have an amorphous structure, high strength, and good corrosion resistance.

Nanomaterials exhibit unique properties due to their small size, including high strength, enhanced reactivity, and unique electrical and optical properties.

Superconductors exhibit zero electrical resistance, expel magnetic fields (Meissner effect), and show the Josephson effect and the persistent current effect.

<p>In semiconductors, energy bands are formed due to the overlapping of atomic orbitals from neighboring atoms. Solids are classified into conductors, semiconductors, and insulators based on the energy band gap. Conductors have overlapping energy bands, semiconductors have a small band gap, and insulators have a large band gap.</p> Signup and view all the answers

<p>Direct band gap semiconductors have their conduction band minimum and valence band maximum at the same momentum. Indirect band gap semiconductors have their conduction band minimum and valence band maximum at different momentum. This difference is significant for optoelectronic applications, as direct band gap semiconductors are more efficient in emitting light.</p> Signup and view all the answers

<p>A semiconductor junction is formed by the contact of p-type and n-type semiconductors. The formation of the depletion region occurs due to the diffusion of majority charge carriers. Current flow across the junction is facilitated by the process of minority carrier injection and recombination.</p> Signup and view all the answers