Ultra-high absorption efficiency of InN nanowires with a wide bandwidth in the short-wave infrared range

The group III-V semiconductor InN is a highly promising candidate for photoelectric detectors in the short-wave infrared (SWIR) range but faces significant challenges in material quality. In recent years, one-dimensional nanowires (NWs) have allowed their high-quality growth and have added structural advantages. However, the performance potential of InN NWs is little known. Here, the optoelectrical properties of hexagonal wurtzite InN NWs were systematically studied. The high absorptivity of InN itself, along with the antenna effect and leaky model resonance, results in the InN NWs exhibiting more than 99% light absorption in the 1000-1470 nm range and a wide range of incidence angles (0-65°). The absorption of InN NW arrays with a low filling factor (FF) of 12.83% can be 34% higher than that of thin film materials of the same thickness and an additional 28% enhancement can be obtained by tilting the NWs. A remarkable response of up to 1 A W^-1 can be explicitly achieved at 1550 nm with precisely arranged InN nanowire arrays. This responsivity is 11.83% higher than that of InGaAs nanowire arrays. The results indicate that InN NWs with outstanding light absorption performance can be used as an efficient photosensitive material in the SWIR range for photovoltaics, detectors, and other optoelectronic devices.