Temporal and amplitude modulation at C-band region using Bi₂Te₃-based optical modulator

ABSTRACT

A temporal and amplitude modulator based on few-layers bismuth telluride (Bi₂Te₃) flakes is demonstrated for C-band operation. The few-layers thick Bi₂Te₃ flakes are prepared by mechanically exfoliating a Bi₂Te₃ crystal. As an optical pulse modulator, the Bi₂Te₃-based saturable absorber (SA) provides stable Q-switching operation at 1561.1 nm with a maximum repetition rate of 70.92 kHz and minimum pulse width of 2.38 µs. As an optical amplitude modulator, two linear regions at different pump power ranges are obtained in the regression line of the peak intensity. The first linear region covers a pump power range from 0.0 to 80.32 mW and corresponds to a modulation efficiency of 0.05 dB/mW, while the second linear region covers a pump power range of 80.32–98.64 mW with a modulation efficiency of 0.81 dB/mW.

KEYWORDS:

• Topological insulator
• Q-switched
• fibre laser
• pulse modulator
• amplitude modulator
• C-band region

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the University of Malaya [grant numbers: HiCoE Phase II Funding and RU011-2019] and the Ministry of Higher Education, Malaysia [grant number: LRGS (2015) NGOD / UM / KPT].