Measurement of the surface susceptibility and the surface conductivity of atomically thin MoS2 by spectroscopic ellipsometry

Funding: Universita degli Studi di Padova (BIRD170839/17). Acknowledgment: M. M. gratefully acknowledges the support from Dipartimento di Fisica e Astronomia G. Galilei, Universita Degli Studi di Padova. M. M. conceived the idea and wrote the Letter. G. J. and Z. D. prepared the sample under the supervision of X. Z. Measurements and data analysis were done by M. B., M. M., and A. M.