A femtosecond pulse fiber laser at 1935 nm using a bulk-structured Bi2Te3 topological insulator.
We experimentally demonstrate a femtosecond mode-locked, all-fiberized laser that operates in the 2 μm region and that incorporates a saturable absorber based on a bulk-structured bismuth telluride (Bi(2)Te(3)) topological insulator (TI). Our fiberized saturable absorber was prepared by depositing a mechanically exfoliated, ~30 μm-thick Bi(2)Te(3) TI layer on a side-polished optical fiber platform. The bulk crystalline structure of the prepared Bi(2)Te(3) layer was confirmed by Raman and X-ray photoelectron spectroscopy measurements. The modulation depth of the prepared saturable absorber was measured to be ~20.6%. Using the saturable absorber, it is shown that stable, ultrafast pulses with a temporal width of ~795 fs could readily be generated at a wavelength of 1935 nm from a thulium/holmium co-doped fiber ring cavity. This experimental demonstration confirms that bulk structured, TI-based saturable absorbers can readily be used as an ultra-fast mode-locker for 2 μm lasers.
Minwan
M
Jung
Junsu
J
Lee
Joonhoi
J
Koo
Jaehyun
J
Park
Yong-Won
YW
Song
Kwanil
K
Lee
Sangbae
S
Lee
Ju Han
JH
Lee