Ultrafast Third-Order Nonlinear Optical Response of 2D NbS2, NbSe2, ZrTe2, and MoS2 LTMDs in Suspension

In this work, we study the third-order optical nonlinear (NLO) response of 2D layered transition metal dichalcogenide (LTMD) by means of the optical Kerr gate (OKG) technique. Such a technique relies on the nonlinear birefringence experienced by a probe beam after interaction with a pump beam in a nonlinear media, which allows a direct measurement of the third-order nonlinear optical coefficient associated with the effect, besides the response time of the nonlinearity. The materials under investigation are monolayer to a few layers of 2D semiconducting MoS
2
, metallic NbS
2
, NbSe
2
, and semi-metallic ZrTe
2
, all prepared by redox exfoliation method, as reported in [1]. The flakes are suspended in acetonitrile (ACN).