Description:
TECHNOLOGY AREA(S): Sensors
OBJECTIVE: The development of a monolithic beam steerable mid-wave infrared laser with average power output exceeding 10W.
DESCRIPTION: Current infrared countermeasures systems are advancing in terms of utilization of more compact mid-IR lasers known as quantum cascade lasers. However, such systems are still somewhat bulky in their use of gimbaled mounts requiring mechanical beam steering. Opportunities exist to explore the development of a midwave-IR (3-5 micron) monolithic beam steering laser chip which would be many orders of magnitude more compact, less expensive, and have higher performance. Monolithic beam steering is coming of age with wide-spread interest of beam steerable ladar using silicon photonics, but those have been directed to wavelengths in the near infrared. Mid-wave infrared lasers are advancing in terms of power output and reliability to over 1 W per laser (room temperature, continuous wave). In addition some applications only require pulsed formats which allow for significant laser cooling between pulses, aiding in reliability. Also, integrated photonics is producing results in silicon based systems for ladars on chip for future collision avoidance for automobiles. The development of Sb-based type I diode lasers and III-V quantum cascade lasers has progressed to the point that such monolithic arrays can be pursued to achieve much faster and agile beam steering for several applications [1, 2]. Several approaches should be possible to achieve the results from wafer bonded lasers [3, 4] to silicon or germanium integrated photonics platforms to directly steerable arrays in III-V materials. High power single mode VCSELs could also be made from mid-IR laser heterostructures [5]. One such approach has been demonstrated with significant beam steering using tunable photonic crystal effects [6].
PHASE I: Using a proposed monolithic design, show evidence of feasibility of all major elements including both the laser sources and the proposed beam steering photonics. Rudimentary demonstration of mid-wave IR lasers useful for reaching 10 W average power should be made along with designs and feasibility studies showing wide-angle and high-speed electronic beam steering of up to +/- 90 degrees at scan rates exceeding 1 kHz.
PHASE II: Fabrication and testing of the full monolithic beam steering microchip system. Optimization of the laser sources power and coupling efficiency to the beam steering apparatus should be pursued along with the design, implementation, and testing of the wide-angle beam steering devices. Goals for this phase include the achievement of up to +/- 90 degrees and 10 W average power (pulse length should be no shorter than 1 ms) at scan rates over 10 kHz.
PHASE III: Mid-infrared lasers have uses in many military applications and advanced beam steering capabilities with high-speeds add to the potential application areas. Examples include surveillance, imaging, communications, and countermeasures. Dual use applications may include the remote sensing of chemicals, explosives, narcotics, and other warfare agents.
REFERENCES:
1: Leon Shterengas, Rui Liang, Gela Kipshidze, Takashi Hosoda, Gregory Belenky, Sherrie S. Bowman, and Richard L. Tober, Applied Physics Letters, 105, 161112 (2014).
2: J. D. Kirch,1 C.-C. Chang,1 C. Boyle,1 L. J. Mawst,1 D. Lindberg III,2 T. Earles,2 and D. Botez, Applied Physics Letters, 106, 061113 (2015).
3: D. Ristanic, B. Schwarz, P. Reininger, H. Detz, T. Zederbauer, A.M. Andrews, W. Schrenk, and G. Strasser, "Monolithically integrated mid-infrared sensor using narrow mode operationand temperature feedback," Appl. Phys. Lett. 106, 041101 (2015).
4: Y. Zou, K. Vijayraghavan, P. Wray, S. Chakravarty, M.A. Belkin, R. T. Chen, "Monolithically integrated quantum cascade lasers, detectors and dielectric waveguides at 9.5µm for far-infrared lab-on-chip chemical sensing," CLEO Technical Digest, paper STu4I.2 (2015).
5: Kazuyoshi Hirose, Yong Liang, Yoshitaka Kurosaka1, Akiyoshi Watanabe, Takahiro Sugiyama and Susumu Noda, Nature Photonics, Vol. 8, 406-411, May (2014).
6: Yoshitaka Kurosaka, Seita Iwahashi, Yong Liang, Kyosuke Sakai1, Eiji Miyai, Wataru Kunishi, Dai Ohnishi, and Susumu Noda, Nature Photonics, Vol. 4, 447-450, July (2010).
KEYWORDS: Mid-wave Infrared, Laser Beam Steering, Integrated Photonics
