A tunable 3D optofluidic waveguide dye laser via two centrifugal Dean flow streams

Abstract

This paper presents a tunable optofluidic waveguide dye laser utilizing two centrifugal Dean flows. The centrifugal Dean flow increases the light confinement of the dye laser by shaping a three-dimensional (3D) liquid waveguide from curved microchannels. The active medium with the laser dye is dissolved in the liquid core and pumped with an external pump laser to produce stimulated emission. The laser's Fabry-Pérot microcavity is formed with a pair of aligned gold-coated fiber facets to amplify the fluorescent emission. The advantage of the 3D optofluidic waveguide dye laser is its higher efficiency, thus to obtain lasing at a reduced threshold (60%) with higher output energy. The demonstrated slope efficiency is at least 3-fold higher than its traditional two-dimensional equivalent. In addition, the laser output energy can be varied on demand by tuning the flow rates of the two flows. This technique provides a versatile platform for high potential applications microfluidic biosensor and bioanalysis.

Determination of size and refractive index of single gold nanoparticles using an optofluidic chip

“…15,16 Detailed description of the optofluidic chip and experimental setup can be found in supplementary material. Experimental observation of the quasi-Bessel beam is shown in Fig.…”

“…12 For real-time measurement, direct imaging using CCD is essentially impossible due to the diffraction limit. [13][14][15][16] For refractive index measurement, emissivity measurement technique, 17 spectroscopic ellipsometry, 18 reflection and transmission measurements 19 and optical spectrum 20 are not feasible for real-time measurement. And they are incapable to measure the refractive index of single gold nanoparticles.…”

Optofluidic Microlasers based on Femtosecond Micromachining Technology

“…This is one of the main reasons why all the optofluidic microlaser based on Fabry-Perot cavity, which have been fabricated up to now, could not achieve a high quality factor providing emission linewidth of about 3-4 nm. These lasers were fabricated by coating with a metallic film on the side of microfluidic channel or the edge of the fibers used to collect the signal and using the soft-lithography technique to realize the microfluidic circuit [5][6][7][8].…”

“…In general the realization of these devices requires several processing steps, usually combin-ing electron-beam and photo-lithography with soft lithography. Fabry-Perot resonators have also been realized by coating metallic mirrors on the edge of optical fibers or on the sides of the microfluidic channel [5][6][7][8]. Also in these cases the fabrication of the microfluidic structure required many steps resulting in a critical alignment of the laser cavity sub-parts.…”

Optofluidic membrane interferometer: An imaging method for measuring microfluidic pressure and flow rate simultaneously on a chip

“…Lien and Vollmer reported a microfluidic flow sensor based on integrated optical fiber cantilever, but it also requires complicated fabrication and packaging process. 16 As an emerging field, optofluidics has enabled a number of novel optical functional devices built on microfluidic systems, [17][18][19][20][21][22][23] such as optofluidic lens, 24 light sources, [25][26][27] molecule sensors, 28 interferometers, 29,30 optofluidic prism, 31 and color filter. 32 Different from the normal on-chip interferometer that requires optical fibers and complicated package.…”