Wavelength tuning of the spirally drawn whispering gallery mode microfiber lasers and the perspectives for sensing applications.

Shancheng Yang,Xin Zhao,Handong Sun,Yue Wang,Tay Yong Kang Eugene,Hilmi Volkan Demir

doi:10.1364/oe.25.002618

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.

Highlights

Optical microcavities have aroused enormous research interests in the past decades due to the abundant applications in lasers, optoelectronics, chaos studies and quantum electrodynamics [1,2,3,4]
High-Q lasers can be achieved by embedding active materials into the microcavities [7,8,9] and various practical applications have been developed with whispering gallery mode (WGM) microcavities and microlasers, including adddrop filters, switches, memories, optical isolator, biological and chemical sensors, etc [10,11,12,13,14]
Instead of sophisticated processing procedures, the reported polymer microspheres, hemispheres, floating quasi-disk microlasers, microfibers are self-assembled and fabricated by straightforward techniques, such as tip-touching, direct drawing, inject printing, etc [15,16,17,18,19]. These flexible WGM microcavities and microlasers with facile tunability compensate the deficiency of the solid ones and, further broaden the practical applications in optical devices

Summary

Introduction

Optical microcavities have aroused enormous research interests in the past decades due to the abundant applications in lasers, optoelectronics, chaos studies and quantum electrodynamics [1,2,3,4]. Instead of sophisticated processing procedures, the reported polymer microspheres, hemispheres, floating quasi-disk microlasers, microfibers are self-assembled and fabricated by straightforward techniques, such as tip-touching, direct drawing, inject printing, etc [15,16,17,18,19]. These flexible WGM microcavities and microlasers with facile tunability compensate the deficiency of the solid ones and, further broaden the practical applications in optical devices. Our work provides a manageable technique for polymer microfiber array fabrication, and gives the prospect to a highly reliable sensing system which has the potential to be applied in multi-point ultra-small vibration detection and structural health monitoring

Spiral drawing of the microfiber lasers

Characterization of the WGM lasing

Deformation-induced wavelength tuning and the sensing applications

Conclusions