Fiber taper

Cai, M. Painter, O. Vahala, K. J., Observation of critical coupling in a fiber taper to a silica microsphere whispering gallery mode system, Phys. Rev. Lett. 2000, 85, 74 77... 

The OFRR offers an excellent solution to implement pGC. It has a circular cross section by design, which is well compatible with all the GC-related equipments that are currently in use. Moreover, OFRR achieves dual use as the separation column as well as the detection body, which is in sharp contrast with other pGC systems having separate column and detector. By placing an optical fiber taper or a waveguide in contact with the OFRR, we are able to achieve multipoint real-time on-column detection, which greatly simplifies the pGC system. 

Joel, V. Monzon Hernandez, D., Fast detection of hydrogen with nano fiber tapers coated with ultra thin palladium layers, Opt. Express 2005, 13, 5087 5092... 

Fig. 7.20 Microscopic image of a 3 dB fiber taper with the length of 707 pm and waist diameter of 40 pm made by a fusion splicer. Reprinted from Ref. 20 with permission. 2008 Optical Society of America...

Tian, Z. Yam, S. S. Barnes, J. Bock, W. P. Greig J. M. Fraser H. P. Loock R. D. Oleschuk, Refractive index sensing with Mach Zehnder interferometer based on concatenating two single mode fiber tapers, IEEE Photon. Technol. Lett. 2008, 20, 626... 

Usually, an MNF sensor represents the waist of a fiber taper. For this reason, to understand the performance of an MNF evanescent sensor, it is important to understand the structure of the evanescent field of an MNF taper. This subsection briefly describes the theory of MNF tapers. 

Fig. 13.12 (a) Supported polymer MNF with two ends coupled to fiber tapers, (b) Time dependence of the MNF transmittance to alternately cycling air with 75% and 88% relative humidity, (c) Time dependence of the MNF absorbance to cyclic NO nitrogen exposure with N02 concentration from 0.1 to 4 ppm. Inset, dependence of the absorbance over the N02 concentration ranging from 0.1 to 4 ppm. Reprinted from Ref. 22 with permission. 2008 American Chemical Society... 

Knight, J. C. Cheung, G. Jacques, F. Birks, T. A., Phase matched excitation of whispering gallery mode resonances by a fiber taper, Opt. Lett. 1997, 22, 1129 1131... 

The fiber-taper coupling scheme was applied to liquid-immersed water-droplet microsphere resonators by Hossein-Zadeh and Vahala35. The water droplets of diameter 0.5 1 mm were generated by a syringe and immersed in a low refractive immiscible cladding liquid - an index matching oil with a refractive index of 1.3, and trapped on a silica sphere which was fixed to the bottom of a liquid container... 

Hossein Zadeh, M. Vahala, K. J., Fiber taper coupling to whispering gallery modes of fluidic resonators embedded in a liquid medium, Opt. Express 2006, 14, 10800 10810... 

Fig. 19.3 Optofluidic laser setup (cross section view) fiber taper is used to evanescently couple out the laser emission...

Wadsworth, W., Ortigosa-Blanch, A., Krught, 1. et al., Snpercontinnnm generation in photoiuc crystal fibers and optical fiber tapers a novel light sonrce, J. Opt. Soc. Am. B, 19, 2148, 2002. 

Su L., Lee T. H., and Elliott S. R., Evanescent-wave excitation of surface-enhanced Raman scattering substrates by an optical-fiber taper. Opt Lett., 34, 2685-2687 (2009). 

---