optical oscillator
71ALSE — The ALSE (Apollo Lunar Sounder Experiment) (also known as Scientific Experiment S 209, according to NASA designations) was a ground penetrating radar (subsurface sounder) experiment that flew on the Apollo 17 mission. Mission and Science This… …
72Self-pulsation — takes place at the beginning of laser action.As the pump is switched on, the gainin the active medium rises and exceeds the steady state value. The number of photons in the cavity increases, depleting the gain below the steady state value, and so …
73Injection locking — is a high frequency (usually RF, but possibly microwave and optical) phenomenon where an oscillator directly synchronizes to another high frequency signal. In the case of a VCO an injection locking signal may override its low frequency control… …
74Fiber laser — A fiber laser or fibre laser is a laser in which the active gain medium is an optical fiber doped with rare earth elements such as erbium, ytterbium, neodymium, dysprosium, praseodymium, and thulium. They are related to doped fiber amplifiers,… …
75Refractive index — Refraction of light at the interface between two media. In optics the refractive index or index of refraction of a substance or medium is a measure of the speed of light in that medium. It is expressed as a ratio of the speed of light in vacuum… …
76Modelocking — Mode locking is a technique in optics by which a laser can be made to produce pulses of light of extremely short duration, on the order of picoseconds (10 12s) or femtoseconds (10 15s).The basis of the technique is to induce a fixed phase… …
77Metamaterial — Negative index metamaterial array configuration, which was constructed of copper split ring resonators and wires mounted on interlocking sheets of fiberglass circuit board. The total array consists of 3 by 20×20 unit cells with overall dimensions …
78Heterodyne detection — is a method of detecting radiation by non linear mixing with radiation of a reference frequency. It is commonly used in telecommunications and astronomy for detecting and analysing signals.The radiation in question is most commonly either radio… …
79Zero-phonon line and phonon sideband — The zero phonon line and the phonon sideband jointly constitute the line shape of individual light absorbing and emitting molecules (chromophores) embedded into a transparent solid matrix. When the host matrix contains many chromophores, each… …
80Rabi problem — The Rabi problem concerns the response of an atom to an applied harmonic electric field, with an applied frequency very close to the atom s natural frequency. It provides a simple and generally solvable example of light atom interactions.… …
