Plasmonic semiconductor nanogroove array enhanced broad spectral band millimetre and terahertz wave detection

High-performance uncooled millimetre and terahertz wave detectors are required as a building block for a wide range of applications. The state-of-the-art technologies, however, are plagued by low sensitivity, narrow spectral bandwidth, and complicated architecture. Here, we report semiconductor surface plasmon enhanced high-performance broadband millimetre and terahertz wave detectors which are based on nanogroove InSb array epitaxially grown on GaAs substrate for room temperature operation. By making a nanogroove array in the grown InSb layer, strong millimetre and terahertz wave surface plasmon polaritons can be generated at the InSb-air interfaces, which results in significant improvement in detecting performance. A noise equivalent power (NEP) of 2.2x10(-14)WHz(-1/2) or a detectivity (D-*) of 2.7x10(12)cmHz(1/2)W(-1) at 1.75mm (0.171THz) is achieved at room temperature. By lowering the temperature to the thermoelectric cooling available 200K, the corresponding NEP and D-* of the nanogroove device can be improved to 3.8x10(-15)WHz(-1/2) and 1.6x10(13)cmHz(1/2)W(-1), respectively. In addition, such a single device can perform broad spectral band detection from 0.9mm (0.330THz) to 9.4mm (0.032THz). Fast responses of 3.5 mu s and 780ns are achieved at room temperature and 200K, respectively. Such high-performance millimetre and terahertz wave photodetectors are useful for wide applications such as high capacity communications, walk-through security, biological diagnosis, spectroscopy, and remote sensing. In addition, the integration of plasmonic semiconductor nanostructures paves a way for realizing high performance and multifunctional long-wavelength optoelectrical devices.

Automated summary

A high-performance broad-band millimeter and terahertz wave detector based on nanogroove InSb array technology has been developed, offering room temperature operation, broad spectral band detection, and fast response times. The detector has wide applications in high-capacity communications, biological diagnostics, and other fields.