title: K4GeP4Se12: a case for phase-change nonlinear optical chalcogenide.
abstract: We report on broadband nonlinear optical (NLO) responses from a phase-change chalcogenide compound K(4)GeP(4)Se(12). Its glassy phase exhibits unusual second-harmonic generation (SHG) due to the preservation of local crystallographic order. The SHG efficiency of the glassy form can be boosted by more than 2 orders of magnitude by simple heat treatment. Strong SHG and third-harmonic generation from both glassy and crystalline compounds were characterized over a wide wavelength range of 1.2-4.0 μm. Our results imply that K(4)GeP(4)Se(12) can be utilized for various NLO applications in the mid-infrared spectrum.
authors.affiliation: Department of Physics, Applied Physics and Astronomy, Binghamton University, P.O. Box 6000, Binghamton, New York 13902, USA. jjoon@binghamton.edu
authors.forename: J I
authors.initials: JI
authors.lastname: Jang
authors.forename: S
authors.initials: S
authors.lastname: Park
authors.forename: C M
authors.initials: CM
authors.lastname: Harrison
authors.forename: D J
authors.initials: DJ
authors.lastname: Clark
authors.forename: C D
authors.initials: CD
authors.lastname: Morris
authors.forename: I
authors.initials: I
authors.lastname: Chung
authors.forename: M G
authors.initials: MG
authors.lastname: Kanatzidis