@article { ISI:000185354800026,
	title = {Internally excited acoustic resonator for photoacoustic trace detection},
	journal = {APPLIED OPTICS},
	volume = {42},
	number = {27},
	year = {2003},
	month = {SEP 20},
	pages = {5561-5565},
	publisher = {OPTICAL SOC AMER},
	type = {Article},
	address = {2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA},
	abstract = {The quantum-cascade laser can be used as an infrared source for a small portable photoacoustic trace gas detector. The device that we describe uses a quantum-cascade laser without collimating optics mounted inside an acoustic resonator. The laser is positioned in the center of a longitudinal resonator at a pressure antinode and emits radiation along the length of the resonator exciting an axially symmetric longitudinal acoustic mode of an open-ended cylindrical resonator. Experiments are reported with an 8-mum, quasi-cw-modulated, room-temperature laser used to detect N2O. (C) 2003 Optical Society of America.},
	issn = {1559-128X},
	doi = {10.1364/AO.42.005561},
	author = {Danworaphong, S and Calasso, IG and Beveridge, A and Diebold, GJ and C. Gmachl and F. Capasso and Sivco, DL and Cho, AY}
}
