These devices are used to create MISERs, which are also called nonplanar ring oscillators. An injection signal can be used by a "master" one of these devices to control the frequency of a "slave" one. It's not a QWIP, but another type of these devices contains a semiconductor superlattice with a series of quantum wells and relies on inter-sub-band transitions occurring in 
These devices are used to create MISERs, which are also called nonplanar ring oscillators. An injection signal can be used by a "master" one of these devices to control the frequency of a "slave" one. It's not a QWIP, but another type of these devices contains a semiconductor superlattice with a series of quantum wells and relies on inter-sub-band transitions occurring in each well. A type of these devices contains a noble gas halide which dimerizes when exposed to an electric current. These devices are used to supply energy to a deuterium- tritium pellet to produce a high density plasma in inertial confinement fusion. These devices come in quantum cascade and excimer types, and they contain a resonator cavity that surrounds a gain medium, such as titanium-sapphire or helium-neon. Pumping is used in these devices to put more atoms in the excited state than the ground state, thus producing a population inversion. For 10 points, name these devices that produce light via stimulated emission.