Open AccessA femtosecond pulse erbium fiber laser incorporating a saturable absorber based on bulk-structured Bi_2Te_3 topological insulator
Author(s) -
Junsu Lee,
Joonhoi Koo,
Young Min Jhon,
Ju Han Lee
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.006165
Subject(s) - saturable absorption , materials science , femtosecond , fiber laser , ultrashort pulse , laser , topological insulator , mode locking , optics , nanosheet , erbium , optoelectronics , doping , nanotechnology , wavelength , physics , quantum mechanics
We experimentally demonstrate the use of a bulk-structured Bi(2)Te(3) topological insulator (TI) as an ultrafast mode-locker to generate femtosecond pulses from an all-fiberized cavity. Using a saturable absorber based on a mechanically exfoliated layer about 15 μm thick deposited onto a side-polished fiber, we show that stable soliton pulses with a temporal width of ~600 fs can readily be produced at 1547 nm from an erbium fiber ring cavity. Unlike previous TI-based mode-locked laser demonstrations, in which high-quality nanosheet-based TIs were used for saturable absorption, we chose to use a bulk-structured Bi(2)Te(3) layer because it is easy to fabricate. We found that the bulk-structured Bi(2)Te(3) layer can readily provide sufficient nonlinear saturable absorption for femtosecond mode-locking even if its modulation depth of ~15.7% is much lower than previously demonstrated nanosheet-structured TI-based saturable absorbers. This experimental demonstration indicates that high-crystalline-quality atomic-layered films of TI, which demand complicated and expensive material processing facilities, are not essential for ultrafast laser mode-locking applications.