LOOKIN, INC. — Department of Defense SBIR Phase I: N202-125

Description

Among different terahertz instruments, terahertz time-domain spectroscopy (THz-TDS) systems are the most effective tools for realizing terahertz imaging and sensing systems. Although THz-TDS systems offer many unique functionalities, their practical utilization for solving real-world problems has been extremely limited because of the absence of high-performance, multi-pixel detectors that can offer both high data quality and fast data acquisition over a broad frequency range. Existing THz-TDS systems consist of single pixel detectors and require two-dimensional scanning of either the scanned object or the detector. This prevents many potential applications of THz-TDS systems. Developing a broadband terahertz focal plane (THz-FPA) can address this problem; however, realization of a THz-FPA for THz-TDS systems has not been possible yet due to the design restrictions of conventional photoconductive terahertz detectors. To address the limitations of conventional photoconductive detectors and realize the world’s first broadband THz-FPA, Lookin, Inc. proposes the use of a novel terahertz detector design based on plasmonic nanoantennas, which are designed to maximize the interaction between the optical pump and terahertz beams. Our team has recently presented a single-pixel demonstration of this unique detector and achieved record-high sensitivity levels over a very broad terahertz frequency range. In addition, the detector structure is easily scalable to large areas without suffering from increased parasitics. This allows development of THz-FPAs with large filling factors, which utilize the majority of the incident optical pump photons and capture most of the incident terahertz radiation while providing a much easier optical/terahertz alignment compared to conventional photoconductive detectors.   To further explore this technology and develop THz-FPAs consisting of more than 1 kilo-pixels, Lookin, Inc. plans to first build a 64-pixel prototype during the Phase I project. Our company will collaborate with Terahertz Electronics Laboratory at UCLA. The UCLA subcontractor’s extensive expertise in plasmonics and terahertz optoelectronics will help us boost the bandwidth and sensitivity of the terahertz detectors based on plasmonic nanoantennas. Our team will conduct critical feasibility studies that will clearly determine the possible achievable frame rate, signal-to-noise ratio, and detection bandwidth. Our initial calculations show that the 1 kilo-pixel THz-FPA can operate at video frame rates and each pixel of the proposed THz-FPA can offer high SNR levels (>50 dB) with a broad terahertz detection bandwidth (1-3 THz). In addition, the team will conduct research on novel nanofabrication techniques, such as nanoimprinting, for the realization of large pixel-count THz-FPAs with much lower cost and higher throughput. The company will also develop an image reconstruction software to capture real-time 3D images with the developed THz-FPAs.