Ma, PanYu, YiYang, ZhiyongVu, KhuNguyen, ThachMitchell, A.Luther-Davies, BarryMadden, SteveChoi, Duk-Yong2016-06-141094-4087http://hdl.handle.net/1885/103924We report the characteristics of high Q factor chalcogenide ring resonators designed for sensing in the mid-infrared (MIR). The resonators consisted of an exposed Ge11.5As24Se64.5core on a Ge11.5As24S64.5 bottom cladding and were fabricated in the racetrack coupled ring structure. Loaded Q factors at 5.2μm up to 58,000were obtained, corresponding to an intrinsic Q of 145,000 and a waveguide propagation loss of 0.84dB/cm.Author/s retain copyright201510.1364/OE.23.0199692016-06-14