title: Tunable terahertz waves generated by mixing two copropagating infrared beams in GaP.
abstract: By mixing two copropagating coherent beams near 1 microm in a zinc blende GaP crystal, we have efficiently generated coherent terahertz (THz) waves. Such efficient conversion is made possible by use of a rest-strahlen band in the THz region to achieve phase matching in an isotropic crystal. A tuning range as wide as 71.1-2830 microm (0.106-4.22 THz) was achieved, whereas the highest output peak power reached 15.6 W at 173 microm. To obtain such a tuning range we continuously tuned the wavelength of one coherent infrared beam within a bandwidth of approximately 15.3 nm.
authors.affiliation: Department of Electrical and Computer Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Shi
authors.forename: Yujie J
authors.initials: YJ
authors.lastname: Ding