ABSTRACT
Facile and cost-efficient microcavities, as well as the tuning of the optical modes, especially for the application of top-grade optical devices, have been emerging as attractive research fields. In this work, controllable fabrication of the microfiber laser arrays in polymer matrix is achieved by employing the advanced spiral drawing technique. Besides the high-quality whispering gallery mode (WGM) lasing, wavelength tuning is also realized by applying external forces on the polymer matrix, which induce slightly enlarged cavity sizes. Furthermore, the perspectives of utilizing the microfiber arrays as force and strain sensors are discussed and demonstrated.
ABSTRACT
Engineering photonic devices from liquid has been emerging as a fascinating research avenue. Reconfigurably tuning liquid optical micro-devices are highly desirable but remain extremely challenging because of the fluidic nature. In this article we demonstrate an all-liquid tunable whispering gallery mode microlaser floating on a liquid surface fabricated by using inkjet print technique. We show that the cavity resonance of such liquid lasers could be reconfigurably manipulated by surface tension alteration originated from the tiny concentration change of the surfactant in the supporting liquid. As such, remarkable sensing of water-soluble organic compounds with a sensitivity of free spectral range as high as 19.85 THz / (mol · mL(-1)) and the detectivity limit around 5.56 × 10(-3) mol · mL(-1) is achieved. Our work provides not only a novel approach to effectively tuning a laser resonator but also new insight into potential applications in biological, chemical and environmental sensing.
