@article { ISI:000257024100039,
	title = {Multimode regimes in quantum cascade lasers: From coherent instabilities to spatial hole burning},
	journal = {PHYSICAL REVIEW A},
	volume = {77},
	number = {5, B},
	year = {2008},
	month = {MAY},
	publisher = {AMER PHYSICAL SOC},
	type = {Article},
	address = {ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA},
	abstract = {A theoretical and experimental study of multimode operation regimes in quantum cascade lasers (QCLs) is presented. It is shown that the fast gain recovery of QCLs promotes two multimode regimes: One is spatial hole burning (SHB) and the other one is related to the Risken-Nummedal-Graham-Haken instability predicted in the 1960s. A model that can account for coherent phenomena, a saturable absorber, and SHB is developed and studied in detail both analytically and numerically. A wide variety of experimental data on multimode regimes is presented. Lasers with a narrow active region and/or with metal coating on the sides tend to develop a splitting in the spectrum, approximately equal to twice the Rabi frequency. It is proposed that this behavior stems from the presence of a saturable absorber, which can result from a Kerr lensing effect in the cavity. Lasers with a wide active region, which have a weaker saturable absorber, do not exhibit a Rabi splitting and their multimode regime is governed by SHB. This experimental phenomenology is well-explained by our theoretical model. The temperature dependence of the multimode regime is also presented.},
	issn = {1050-2947},
	doi = {10.1103/PhysRevA.77.053804},
	author = {Gordon, Ariel and Wang, Christine Y. and Diehl, L. and Kaertner, F. X. and Belyanin, A. and Bour, D. and Corzine, S. and Hoefler, G. and Liu, H. C. and Schneider, H. and Maier, T. and M. TROCCOLI and Faist, J. and Federico Capasso}
}
