Scalable Receivers Based on Horizontally-grown InAs Nanowires Promise All-fiber Terahertz Spectrometer Systems

Nanowire-based terahertz photoconductive receivers offer many advantages over the existing bulk-based receivers, such as the capability of measuring the full terahertz polarization state and integrating into micro/nano-systems. However, their detection performance, e.g. signal-to-noise ratio, needs to be further improved to meet the demands of practical applications. In this work, we demonstrate wafer-scalable horizontally-grown parallel-InAs nanowire receivers that are compatible with gating lasers across the entire range of telecom wavelengths (1.2-1.6 μm), ideal for inexpensive all-optical fiber-based THz time-domain spectroscopy and imaging systems. The photoconductivity lifetimes of the nanowires can be controlled by facet engineering, allowing the detection of terahertz photons via both direct and integrating sampling modes, which is beneficial for optimizing detection performance.