Cavity lasing

D.N. Kumar, J.D. Bhawalkar, P.N. Prasad, F.E. Karasz, B. Hu, Solid-slate tunable cavity lasing in a poly(para-phcnylene vinylene) derivative alternating block co-polyniei Appl. Phys. Lett 1997, 71. 999. 

D. N. Kumar, J. D. Bhawalkar, P. N. Prasad, SoUd-state cavity lasing from polytp-phenylenevinyl-ene)-siUca nanocomposite bulk, Applied Optics 1998, 37, 510. 

Fig. 6.13 The microcavity, a vertical cavity lasing device, (a) Schematic depiction of the device, consisting of a distributed Bragg reflector, a PPV layer, and a silver layer.

Fig. 2.28. Top view of the amplifier cavity (Quantronix model RGA 4810). The KD P (KD2PO4) Pockels cell (PC, Medox Electro-Optics) has a dual function. First, it frustrates cavity lasing except for a brief time period when the seed pulse is accepted for amplification. Secondly, in combination with the thin-film polarizer (TFP), it also controls the injection of the seed pulse and extraction of the amplified pulse. The Pockels cell operates at IkHz. A photodetector is provided for intracavity power monitoring, which is necessary for adjusting the two time delays of the Pockels cell driver (by courtesy of Quantronix)...

Lowered refractive index and absorption coefficient in skin up to three atomic layers may find application for waveguides, cavity lasing, and high reflectivity in optical devices. 

Photons of energy hcv are generated initially in the cavity through spontaneous emission. Those that strike the cavity mirrors at 90° are retained within the cavity causing the photon flux to reach a level which is sufflciently high to cause stimulated emission to occur, and the active medium is said to lase. 

Lasing occurs whenever the gain arising from stimulated emission exceeds the cavity losses. Internal losses, a, result from absorption and scattering of light. The reflectivity, R, of the mirror facet must be <1 and this contributes a loss term of (1/L)ln(l/E), where Eis the cavity length. At threshold, the gain, is equal to losses and... 

Fig. 19.6 Lasing peak of the etched laser cavity in different dye concentrations of ethanol solutions. Reprinted from Ref. 20 with permission. 2008 International Society for Optical...

Lasers, 9 729 14 654-706. See also Lasing atomic systems in, 14 666-669 basic mechanism of, 14 656—661 buried heterostructure, 14 701 carbon dioxide, 14 693-696 carbon monoxide application, 5 24 cavity optics and, 14 669-672 classes of, 14 666-667 cutting applications of, 14 695-696 dye, 14 702-705 effect of loss in, 14 670 excimer, 14 691-693 fast pulse production in, 14 673-678 fiber optics and, 11 129 in fine art examination/conservation, 11 412, 413... 

As we reported in Section IV.A, refraction and total internal reflection can occur in dye-loaded zeolite L microcrystals. Therefore, a bundle of light rays in, for example, a POPOP-loaded zeolite composite can circulate inside the hexagon. If the emission can circulate often enough in the same volume and the loss of the zeolite L ring cavity is small enough, lasing should be possible. 

To overcome the lasing threshold, the light amplification has to be larger than unity. For this reason, the loss from the cavity has to be small. Whereas the length of one round-trip in the largest crystals we are using is 3 p.m, it is about... 

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