Broadband photoresponse arising from photo-bolometric effect in quasi-one-dimensional Ta2Ni3Se8.

ABSTRACT

In this paper, we report the synthesis of high-quality Ta2Ni3Se8crystals free of noble or toxic elements and the fabrication and testing of photodetectors on the wire samples. A broadband photoresponse from 405 nm to 1550 nm is observed, along with performance parameters including relatively high photoresponsivity (10 mA W-1) and specific detectivity (3.5 × 107Jones) and comparably short response time (τrise= 433 ms,τdecay= 372 ms) for 1064 nm, 0.5 V bias and 1.352 mW mm-2. Through extensive measurement and analysis, it is determined that the dominant mechanism for photocurrent generation is the photo-bolometric effect, which is believed to be responsible for the very broad spectral detection capability. More importantly, the pronounced response to 1310 nm and 1550 nm wavelengths manifests its promising applications in optical communications. Considering the quasi-one-dimensional structure with layered texture, the potential to build nanodevices on Ta2Ni3Se8makes it even more important in future electronic and optoelectronic applications.