Seeded amplification of amplified spontaneous emission in NO

Ogi, Y Sakoda, A Tsukiyama, K

Y. Ogi et al., Seeded amplification of amplified spontaneous emission in NO, J CHEM PHYS, 113(4), 2000, pp. 1426-1433

22

INGLESE

Article

Physical Chemistry/Chemical Physics

JOURNAL OF CHEMICAL PHYSICS

0021-9606 → ACNP

113

4

2000

1426 - 1433

ISI

0021-9606(20000722)113:4<1426:SAOASE>2.0.ZU;2-J

Two techniques are presented for control of cascade-type amplified spontane ous emission (ASE) pathways in the NO Rydberg states. The first method, ref erred to as switching, is based on destruction of the population inversion required for amplification. When one of the two competing ASE decay paths i s prohibited by prepopulating the corresponding lower level, a part of the population in the upper level flows down through the other ASE decay path, resulting in the enhancement of this ASE transition. The second method, cal led seeding, utilizes the injection of external field. The weak ASE radiati on generated in a seeder cell travels collinearly with pump beams, acting a s seeder light for the inverted medium in a main cell. By extracting desire d seeder wavelengths with optical filtering, amplification of the selected electronic transition is realized. In addition, selective enhancement betwe en the rotational transitions belonging to the same inter-Rydberg system is achieved by taking advantage of their different polarization properties. F inally, the combined use of switching and seeding, also providing rotationa l selectivity, is described. (C) 2000 American Institute of Physics. [S0021 -9606(00)00528-6].