In:
Optics Express, Optica Publishing Group, Vol. 29, No. 6 ( 2021-03-15), p. 9252-
Abstract:
Excitation of ultraviolet (UV) range plasmon resonance with high quality ( Q )-factor has been significantly challenging in plasmonics because of inherent limitations in metals like Au and Ag. Herein, we theoretically investigated UV-visible range plasmons in the topological insulator Bi 1.5 Sb 0.5 Te 1.8 Se 1.2 (BSTS) nanosphere and nanoshell. In contrast to broad linewidth plasmon absorptions in the BSTS nanospheres, an ultra-sharp absorption peak with the Q -factor as high as 52 is excited at UV frequencies in the BSTS nanoshells. This peak is attributed to Dirac-type plasmon resonance originating from massless Dirac carriers in surface states of the BSTS. Furthermore, a tunable plasmon wavelength of the resonance is demonstrated by varying geometrical parameters of the BSTS nanoshells. This may find applications in surface enhanced Raman spectroscopies, nanolasers and biosensors in the UV regions.
Type of Medium:
Online Resource
ISSN:
1094-4087
Language:
English
Publisher:
Optica Publishing Group
Publication Date:
2021
detail.hit.zdb_id:
1491859-6
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