In:
Advanced Science, Wiley, Vol. 9, No. 36 ( 2022-12)
Abstract:
Despite the interest toward the terahertz (THz) rapidly increasing, the high‐efficient detection of THz photon is not widely available due to the low photoelectric conversion efficiency at this low‐energy photon regime. Excitonic insulator (EI) states in emerging materials with anomalous optical transitions and renormalized valence band dispersions render their nontrivial photoresponse, which offers the prospect of harnessing the novel EI properties for the THz detection. Here, an EI‐based photodetector is developed for efficient photoelectric conversion in the THz band. High‐quality EI material Ta 2 NiSe 5 is synthesized and the existence of the EI state at room temperature is confirmed. The THz scanning near‐field optical microscopy experimentally reveals the strong light–matter interaction in the THz band of EI state in the Ta 2 NiSe 5 . Benefiting from the strong light–matter interaction, the Ta 2 NiSe 5 ‐based photodetectors exhibit superior THz detection performances with a detection sensitivity of ≈42 pW Hz −1/2 and a response time of ≈1.1 µs at 0.1 THz at room temperature. This study provides a new avenue for realizing novel high‐performance THz photodetectors by exploiting the emerging EI materials.
Type of Medium:
Online Resource
ISSN:
2198-3844
,
2198-3844
DOI:
10.1002/advs.202204580
Language:
English
Publisher:
Wiley
Publication Date:
2022
detail.hit.zdb_id:
2808093-2