Non-Linear Near-Infrared Spectroscopy Concepts for Remote Sensing
EMSL Project ID
42193
Abstract
Linear forms of LIDAR, such as fluorescence or FM-DIAL, have proved ineffective for remotely detecting low concentration or otherwise transient compounds in the atmosphere, especially under standard conditions of atmospheric pressure and moderate humidity (> 30 %). Published theoretical proposals by Prof. Marlan Scully's group suggest ultra-fast nonlinear stimulated emission Lidar concepts can better detect molecules before collisional broadening, internal energy exchange and reactions diminish their net output signal.1-3 Scully's techniques induce efficient backscatter in a highly directional return beam that avoids radiative losses to all 4-pi steradians. They propose ultra-fast (sub-picosecond) VIS/UV lasers to induce coherent transients (CTs) to avoid large signal losses like hydrolysis, collisional relaxation, etc., that occur near the earth's surface. We have reviewed these ideas and consider that several simpler concepts of inducing highly directional backscattered CTs would also work and, importantly, could probably be implemented without using the proposed ultra-fast (sub-picosecond) stimulation to proceed.
Project Details
Start Date
2010-08-16
End Date
2013-08-25
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members