In:
Advanced Optical Materials, Wiley, Vol. 7, No. 19 ( 2019-10)
Abstract:
Topological insulators are a new class of materials with highly interesting optoelectronic properties such as strong light absorption, polarization‐dependent surface photocurrent, and topological phase transitions. In the present study, anomalous characteristics of the topological surface state (TSS) are discovered in a single‐crystalline Bi 2 Te 3 nanowire (NW) through mediated optical transitions by utilizing an optical pump‐THz probe. As a result, ultra‐fast carrier recombination occurs owing to the presence of TSS, and a phonon frequency shift occurs due to enhanced electron–phonon interaction. In particular, the large optical absorption of the second TSS is closely related to high optical conductivity. The photoresponse for visible light in Bi 2 Te 3 NW with TSS represents a remarkable improvement. The result indicates that the presence of (first and second) TSS and quantum well 2D electron gas effectively contributes to the significant improvement in photocurrent sensitivity by enhancement of the photocurrent generation. In summary, TSS‐assisted optical transitions affect the efficiency of the optoelectronic device.
Type of Medium:
Online Resource
ISSN:
2195-1071
,
2195-1071
DOI:
10.1002/adom.201900621
Language:
English
Publisher:
Wiley
Publication Date:
2019
detail.hit.zdb_id:
2708158-8
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