Open AccessHolographic fabricated photonic-crystal distributed-feedback quantum cascade laser with near-diffraction-limited beam quality
Author(s) -
Qing Lü,
Wei Zhang,
Li Jun Wang,
Jun Qi Liu,
Lü Li,
Feng Qi Liu,
Zhan Guo Wang
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.018900
Subject(s) - optics , materials science , laser beam quality , photonic crystal , laser , electron beam lithography , optoelectronics , holography , cascade , quantum cascade laser , diffraction , beam divergence , diffraction efficiency , lithography , physics , laser beams , resist , chemistry , layer (electronics) , chromatography , composite material
We demonstrate the fabrication and characterization of photonic-crystal distributed-feedback quantum cascade laser emitting at 4.7 microm. The tilted rectangular-lattice PCDFB structure was defined using a multi-exposure of two-beam holographic lithography. The devices exhibit the near-diffraction-limited beam emission with the full width at half maximum of the far-field divergence angles about 4.5 degrees and 2.5 degrees for stripe widths of 55 microm and 95 microm, respectively. Single-mode emission with a side mode suppression ratio of approximately 20 dB is achieved in the temperature range (80-210 K). The single-facet output power is above 1 W for a 95 microm x 2.5 mm laser bar at 85 K in pulsed operation.