  We have demonstrated what we believe to be the first waveguide photonic
crystal cavity operating in the mid-infrared. The devices were fabricated from
Ge23Sb7S70 chalcogenide glass on CaF2 substrates by combing photolithographic
patterning and focus ion beam milling. The waveguide-coupled cavities were
characterized using a fiber end fire coupling method at 5.2 {\mu}m wavelength,
and a loaded quality factor of ~ 2,000 was measured near the critical coupling
regime.
