Published/Posted: March 1, 2016

Authors: R. J. Suess, M. M. Jadidi, T. E. Murphy and M. Mittendorff

Abstract: Black phosphorus is a two-dimensional material that has recently attracted interest due to its high mobility and direct bandgap. In this work we examine the pump-induced change in optical transmission of mechanically exfoliated black phosphorus flakes using a two-color optical pump-probe measurement. The time-resolved data reveal a fast pump-induced transparency accompanied by a slower absorption that we attribute to Pauli blocking and free-carrier absorption, respectively. Polarization studies show that these effects are also highly anisotropic - underscoring the importance of crystal orientation in the design of optical devices based on this material. Ongoing work suggests that exploring the carrier density dependence of the pump-probe signals, which can be accessed experimentally via electrostatic gating, may allow for improved understanding of the optical response and carrier dynamics in the material.

R. J. Suess, M. M. Jadidi, T. E. Murphy and M. Mittendorff, "Transmission pump-probe spectroscopy on multilayer black phosphorus", APS March Meeting, Baltimore, MD (USA) BAPS.2016.MAR.L16.8 (2016)