Investigation of light-matter interaction in single vertical nanowires in ordered nanowire arrays.
Nanoscale 14:9 (2022) 3527-3536
Abstract:Quasi one-dimensional semiconductor nanowires (NWs) in either arrays or single free-standing forms have shown unique optical properties (i.e., light absorption and emission) differently from their thin film or bulk counterparts, presenting new opportunities for achieving enhanced performance and/or functionalities for optoelectronic device applications. However, there is still a lack of understanding of the absorption properties of vertically standing single NWs within an array environment with light coupling from neighboring NWs within certain distances, due to the challenges in fabrication of such devices. In this article, we present a new approach to fabricate single vertically standing NW photodetectors from ordered InP NW arrays using the focused ion beam technique, to allow direct measurements of optical and electrical properties of single NWs standing in an array. The light-matter interaction and photodetector performance are investigated using both experimental and theoretical methods. The consistent photocurrent and simulated absorption mapping results reveal that the light absorption and thus photoresponse of single NWs are strongly affected by the NW array geometry and related light coupling from their surrounding dielectric environment, due to the large absorption cross section and/or strong light interaction. While the highest light concentration factor (∼19.64) was obtained from the NW in an array with a pitch of 1.5 μm, the higher responsivity per unit cell (equivalent to NW array responsivity) of a single vertical NW photodetector was achieved in an array with a pitch of 0.8 μm, highlighting the importance of array design for practical applications. The insight from our study can provide important guidance to evaluate and optimize the device design of NW arrays for a wide range of optoelectronic device applications.
The application of one-dimensional nanostructures in terahertz frequency devices
APPLIED PHYSICS REVIEWS 8:4 (2021) ARTN 041314
Selective area epitaxy of III-V nanostructure arrays and networks: Growth, applications, and future directions
APPLIED PHYSICS REVIEWS 8:2 (2021) ARTN 021302
Nanowires: A new horizon for polarization-resolved terahertz time-domain spectroscopy
Optics InfoBase Conference Papers (2021)
Abstract:In this study, a novel type of broadband polarization-sensitive photoconductive terahertz detectors based on crossed nanowire networks is demonstrated, enabling fast and precise polarization terahertz time-domain spectroscopy measurements.
Three-dimensional cross-nanowire networks recover full terahertz state
Science American Association for the Advancement of Science 368:6490 (2020) 510-513