Investigationg On The Generation Of Optofluidic Laser In A Fabry-Perot Microcavity Based On Fiber

Optofluidic is to integrate optical elements into microfluidic chip,in order to improve the function integration and portability of microfluidic analysis system.Among them,optofluidic laser is a chip laser with organic dyes dissolved in liquid and used as gain medium and optical microcavity as laser resonant cavity,and combining with microfluidic technology.Optofluidic laser,an important branch of microfluidic device,has wide applications in the integrated coherence light source and bio-and chemical detection based on laser signal,et al.The researchers,relying on different optical microcavities and laser resonance forms,have achieved various forms of optofluidic laser based on various optical microcavities for laser resonating,such as Pabry-Perot cavity,implantable distributed Bragg grating,droplet and optical ring resonator based on Whispering Gallery Modes(WGM)and Photonic crystal cavity.The main work is to investigate the generation of Optofluidic Laser in Fabry-Perot Microcavity and one of the mirrors of the FP cavity is a micro concave mirror based on the optical fiber end face.The plano-concave FP microcavity,compared to the general FP cavity with plano-plano mirrors,has higher stability.Meanwhile,using the optical fiber as cavity mirror is easy to realize the integration of the microfluidic devices.The program of our work can be divided into several parts:1.We set the platform of CO2 laser processing and the concave structures were created on the end face of optical fibers using a single CO2 laser pulse,which is 3-10 micrometers in depth and 40-110 micrometers in transverse diameter.Then,the end face of optical fibers are coated with the distributed Bragg reflection(DBR)layers in order to achieve the 99.9% reflectivity on the centre wavelength.At the same time,the concave and plano mirrors based on fused silica are created,followed by coating of distributed Bragg reflection(DBR)layers.2.Using nanosecond pulse laser as the pump source,Optofluidic laser,based on open plano-concave FP cavity made by the concave mirror created on the end face of optical fiber and the plano mirror created on the silica,can be achieved with the 2 ?M coumarin 6.3.In order to fabricate the optofluidic laser chip,the closed plano-concave FP cavity based on optical fibers and optofluidic systems,combined with PDMS encapsulation technology,are created,achieving the integration of optofluidic laser devices.Using nanosecond pulse laser as the pump source,laser threshold as low as 31.46 ?J/mm2 can be achieved with the 10 ?M coumarin 6 and Optofluidic laser can be generated with 3 ?M coumarin 6 as the gain medidum based on the chip.Our work will further promote the integration of optofluidic laser devices based on the optical fiber and the development of the optofluidic laser detection technology with small volume and high sensitivity.It also promote the development of the novel photonic devices.