Photonics Dictionary: M

media access unit — A media access unit (MAU) is a unique device utilized to connect token ring devices from multiple network stations into a star topology. There are two types of MAUs, passive and active. Passive MAUs are powered from their network connections while active MAUs are powered electrically from an external source.

molecular beam epitaxy — A well-controlled thin film technique for growing films with good crystal structure in ultra high vacuum environments at very low deposition rates. MBE is also commonly used in the manufacture of semiconductor devices and solar cells.