title: Low-loss chalcogenide waveguides on lithium niobate for the mid-infrared.
abstract: We demonstrate low-loss chalcogenide (As(2)S(3)) waveguides on a LiNbO(3) substrate for the mid-IR wavelength (4.8 μm). Designed for single-mode propagation, they are fabricated through photolithography and dry-etching technology and characterized on a mid-IR measurement setup with a quantum cascade laser. For straight waveguides, propagation loss as low as 0.33 dB/cm is measured and low-loss bends on the order of 100 μm are simulated, with measurement results showing <3 dB for a 250 μm bend radius. The coupling efficiency is estimated to be 81%. In addition, the influences of variations in width and bend radius are also investigated.
authors.affiliation: Photonics and Nano-Engineering Laboratory, Department of Electrical and Computer Engineering, Texas A&M University, College Station, Texas 77843, USA. xinxia@neo.tamu.edu
authors.forename: Xin
authors.initials: X
authors.lastname: Xia
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
authors.forename: Candice
authors.initials: C
authors.lastname: Tsay
authors.forename: Craig B
authors.initials: CB
authors.lastname: Arnold
authors.forename: Christi K
authors.initials: CK
authors.lastname: Madsen