We present nonlinear optical absorption properties of pulsed laser deposited thin films of
topological insulator (TI), Bi 2 Se 3 on a quartz substrate, using an open aperture z-scan
technique. We observed saturable absorption with a low saturation intensity in as deposited
thin films. Past results from the literature are inconclusive in establishing whether the
saturable absorption in TI is coming from surface states or the bulk. Specifically designed
experiments with magnetically doped TI samples allow us to attribute the saturable …

We present nonlinear optical absorption properties of pulsed laser deposited thin films of
topological insulator (TI), Bi2Se3 on quartz substrate, using open aperture Z-scan technique.
The saturable intensity of as-deposited thin films has been found remarkably improved by an
order of magnitude compared to the values reported earlier in the literature. Past results from
the literature are inconclusive in establishing whether the saturable absorption is coming
from surface states or the bulk. Specifically designed experiments with magnetically doped …