Picture of two heads

Open Access research that challenges the mind...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs. Strathprints provides access to thousands of Open Access research papers by University of Strathclyde researchers, including those from the School of Psychological Sciences & Health - but also papers by researchers based within the Faculties of Science, Engineering, Humanities & Social Sciences, and from the Strathclyde Business School.

Discover more...

Delayed rapid passage and transient gain signals generated using a chirped 8 mu m quantum cascade laser

Duxbury, G. and Langford, N. and Hay, K.G. (2008) Delayed rapid passage and transient gain signals generated using a chirped 8 mu m quantum cascade laser. Journal of Modern Optics, 55 (19-20). pp. 3293-3303.

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

Rapid passage signals have been observed in which a delayed switch from absorption to emission is observed as the optical density of acetylene in a long path length cell is increased. The delayed switch results in the generation of a large, narrow, transient gain signal. Using numerical solutions of the Maxwell-Bloch equations we have demonstrated that this effect is due to constructive interference between the incident laser field and the field generated by the response of the gaseous medium. This occurs owing to the minimal collisional damping at the low gas pressures within the gas cell, so that the chirp rate of the laser is faster than the collisional reorientation time of the molecules.