All-fiber micromachined microcell

This Letter presents an open-path, all-fiber microcell and a micromachining method for its production. The proposed micromachining method utilizes the selective etching of a purposely designed phosphorus-doped fiber that is spliced in between two standard lead-in fibers. Microcells with various open optical-path lengths were successfully demonstrated. The proposed microcell can be used as a transmission cell or as a miniature Fabry-Perot resonator. The transmission losses and fringe contrast were experimentally investigated over a range of prototype microcells with different lengths. For example, the insertion losses below 1 dB were demonstrated for 50 μm or shorter open path prototype microcells, when immersed in dematerialized water.