Investigation of second- and third-harmonic generation in few-layer gallium selenide by multiphoton microscopy

Lasse Karvonen; Antti Säynätjoki; Soroush Mehravar; Raul D Rodriguez; Susanne Hartmann; Dietrich R T Zahn; Seppo Honkanen; Robert A Norwood; N Peyghambarian; Khanh Kieu; Harri Lipsanen; Juha Riikonen

doi:10.1038/srep10334

Investigation of second- and third-harmonic generation in few-layer gallium selenide by multiphoton microscopy

Sci Rep. 2015 May 19:5:10334. doi: 10.1038/srep10334.

Affiliations

¹ Aalto University, Department of Micro and Nanosciences, Tietotie 3, FI-02150 Espoo, Finland.
² University of Arizona, College of Optical Sciences, 1630 E University Blvd, Tucson, AZ 85721, USA.
³ Technische Universität Chemnitz, Semiconductor Physics, Chemnitz 09107, Germany.
⁴ University of Eastern Finland, Institute of Photonics, P.O. Box 111, FI-80101 Joensuu, Finland.
⁵ 1] Aalto University, Department of Micro and Nanosciences, Tietotie 3, FI-02150 Espoo, Finland [2] University of Arizona, College of Optical Sciences, 1630 E University Blvd, Tucson, AZ 85721, USA [3] University of Eastern Finland, Institute of Photonics, P.O. Box 111, FI-80101 Joensuu, Finland.

Abstract

Gallium selenide (GaSe) is a layered semiconductor and a well-known nonlinear optical crystal. The discovery of graphene has created a new vast research field focusing on two-dimensional materials. We report on the nonlinear optical properties of few-layer GaSe using multiphoton microscopy. Both second- and third-harmonic generation from few-layer GaSe flakes were observed. Unexpectedly, even the peak at the wavelength of 390 nm, corresponding to the fourth-harmonic generation or the sum frequency generation from third-harmonic generation and pump light, was detected during the spectral measurements in thin GaSe flakes.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.