Z-scan characterization of two-dimensional transition metal dichalcogenide few-layer sheets

The Z-scan technique was applied to investigate the nonlinear absorption and refraction in few layer sheets of 2D transition metal dichalcogenide: WS
2
, MoS
2
, WSe
2
and Mo
0.5
W
0.5
S
2
, which showed nonlinear saturable absorption and two photon absorption.