摘要:
An external cavity laser comprises a gain medium and an external cavity resonator without the use of a semi-reflective surface placed between the gain medium and the resonator. Radiation from the gain medium is reflected back to the gain medium by one or more resonant backscattering regions of the resonator, such that the entire optical path between the gain medium and the external cavity resonator could be free from a reflective surface.
摘要:
Improved laser sources for the generation of terahertz radiation which comprise a semiconductor diode laser for generating optical pulses for integration into a THz pulse generation system wherein the pulse generator comprises an ultrabroadly tunable quantum dot (QD) based laser diode (191) which acts as a single or dual-mode optical pump source. The QD is deposited in layers which may be in a range of physical sizes, dot densities and layer spacings. The external cavity may comprise a beam splitter (187) and two diffraction gratings (197) for individual control of the two wavelengths emitted via the opposite face of the QD gain chip (191). THz radiation is generated at the frequency difference of these two laser wavelengths.
摘要:
A mode-monitoring system used in connection with discrete beam frequency tunable laser provides optical feedback that can be used for adjusting the laser or for other processing associated with the use of the laser. For example, the output of a frequency tunable source for a frequency-shifting interferometer can be monitored to support the acquisition or processing of more accurate interference data. A first interferometer for taking desired measurements of optical path length differences traveled by different portions of a measuring beam can be linked to a second interferometer for taking measurements of the measuring beam itself. The additional interference data can be interpreted in accordance with the invention to provide measures of beam frequency and intensity.
摘要:
An integrated structure includes front and rear facets (201, 203) optically- coupled by a waveguide (220) passing through the integrated structure. The integrated structure includes a gain section (202) and a reflector (208) optically coupled to the gain section by the waveguide, the reflector to emit an optical output. A modulator (214) is optically coupled to the reflector by the waveguide, the modulator to modulate the optical output. And a control section (216) disposed along the waveguide.