TECHNOLOGY AREA(S): Air Platform

ACQUISITION PROGRAM: PMA-272 Tactical Aircraft Protection Systems

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with section 3.5 of the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.

OBJECTIVE: Develop a two-dimensional beam steerer that is monolithically integrated with a mid-infrared Quantum Cascade Laser (QCL) or QCL array in a single common semiconductor substrate with no mechanically moving components of any kind.

DESCRIPTION: An infrared countermeasures (IRCM) system is typically composed of two separate optical systems. The first is the optical emitter that is now primarily based on QCL. The second system is a mechanically-based gimbal mount, which is used to steer optical energy to a remote target. A typical gimbal's size and weight are over 100 times more than those of the light emitters. Furthermore, due to the gimbal's mechanical nature, the average steering time of laser beams via a gimbal is in the order of seconds. That is many orders of magnitude longer than the steering time of a beam that can be steered via electronic means without any mechanical moving elements. Unlike a typical gimbal unit, the monolithic steering mechanism via electronic control with no mechanical moving parts is substantially more robust and reliable by design. This is because the QCL or QCL array plus the steering device as a single monolithic integrated unit is not susceptible to shocks, vibrations, and extreme temperature variations. This is in stark contrast to many other hybrid designs pursued by others within the DoD, which all have the inherent drawback of being unreliable within military operating conditions. Hence, eliminating the need for a mechanical gimbal or other hybrid integration of QCLs with external beam steering device (using either butt coupling or fiber coupling in the next-generation IRCM system) would significantly improve the size, weight, performance, and reliability of the system by at least a factor of 10 to 50. That would thereby open up the unprecedented possibility of integrating the IRCM system with increasingly more compact manned or unmanned aerial aircrafts in the future that would otherwise not be able to accommodate the payload.

Compact, electrically controlled two-dimensional (2-D) beam steering devices based on hybrid integration of laser emitters and waveguide phase array have been demonstrated in the near infrared regime [Ref 1, 2]. Other hybrid non-mechanical beam steering devices based on hybrid integration of laser emitters via butt coupling of phase shifters, waveguide chips, and optics have been pursued with some successes in laboratory setting. However, hybrid optical butt coupling of a laser array to phase shifter/passive waveguide chips with multiple inputs and outputs is inherently unreliable by design, as the required extremely precise optical alignment of the chips is imperative for the entire optical assembly to function properly. It is very sensitive to temperature variations, shocks, and vibrations. In other words, even if such a design performs well in the laboratory, it cannot be transitioned to eventual field deployment, as the product will not meet MIL-STD-810 requirements.

It is therefore the goal of this project to develop a 2-D beam steering device that can be monolithically integrated with a mid-infrared QCL or QCL array in a single common semiconductor platform with no mechanically moving components and hybrid integration of any kind. The integrated device will be required to emit room-temperature continuous wave (CW) output power > 1 W at a wavelength ~4.6 micron with near diffraction-limited beam quality (M2 < 1.5). The steering angles of the output emission via electronic and non-mechanical control must be at least �10 and �25 degrees horizontally and vertically from the surface normal perpendicular to the device�s emission surface. The beam steering design can be based on the optical phased array within a photonic integrated circuit in which the relative phase of each of the array waveguide can be independently controlled. Besides the phased array approach, other designs and approaches will also be considered if the designs are deemed to be monolithic in nature and capable of meeting the specifications stated in this SBIR topic.

PHASE I: Develop and conduct a proof-of-concept evaluation to demonstrate a viable and manufacturable design for a 2-D beam steering device that can be monolithically integrated with a mid-infrared QCL or QCL array in a single common semiconductor platform with no mechanically moving components and no hybrid integration of any optical elements. Ensure that the integrated device emit room-temperature continuous wave (CW) output power > 1 W at a wavelength ~4.6 micron with near diffraction-limited beam quality (M2 < 1.5). Ensure that the steering angles of the output emission via electronic and non-mechanical control are at least �10 and �25 degrees horizontally and vertically from the surface normal perpendicular to the device�s emission surface. Propose a viable design path forward in Phase II for further increasing steering angle range as part of the deliverable for Phase I.

PHASE II: Fabricate and demonstrate a prototype steering device that is capable of emitting room-temperature CW output power > 1 W at a wavelength ~4.6 micron with near diffraction-limited beam quality (M2 < 1.5) and output emission steering angles at least �10 and �25 degrees horizontally and vertically from the surface normal perpendicular to the device�s emission surface.

PHASE III DUAL USE APPLICATIONS: Fully develop and transition the high-performance monolithic beam steerer for high-power, mid-infrared quantum cascade lasers for DoD applications in the areas of Directional Infrared Countermeasures (DIRCM), advanced chemicals sensors, and Light Detection and Ranging (LIDAR).

The DoD has a need for advanced, compact, high-performance Mid-Wave Infrared (MWIR) QCL monolithically integrated with beam steerer for current- and future-generation DIRCMs, LIDARs, and chemicals/explosives sensing. The commercial sector can also benefit from this crucial, game-changing technology development in the areas of detection of toxic gases, environmental monitoring, and non-invasive health monitoring and sensing.

REFERENCES:

1. Hulme, J. C. et al. (2015). �Fully integrated hybrid silicon two dimensional beam scanner�. Optics Express, 2015, Vol 23, Issue 5, p. 5861. https://doi:10.1364/OE.23.005861

2. Van Acoleyen, K., Bogaerts, W., et al. �Off-chip beam steering with a one-dimensional optical phased array on silicon-on-insulator�, Optics Letters, 2009, Vol. 34, Issue 9, pp. 1477-1479. https://doi.org/10.1364/OL.34.001477

KEYWORDS: Monolithic Beam Steerer; Mid-infrared; Quantum Cascade Lasers; High Power; Gimbal; Infrared Countermeasures