Ring resonator configurations

So far, there are four basic ring resonator configurations that can potentially be used as a vapor sensor, the first three of which are shown in Fig. 6.1. They include... 

In this chapter, we introduce the fundamentals of ring resonator sensors and provide an overview of this novel technology. Various ring resonator configurations are discussed and their sensing performances are compared. The applications of ring resonators in detection of chemical and biological molecules are also described. 

Ring Resonator Configurations 3.1 Microsphere Ring Resonator... 

Figure 4.11 CW dye Laser with ring-resonator configuration, exhibiting unidirectional beam drculation (using an optical diode device). HR high-reflecting mirrors OC output coupler...

Fig. 6.1 Various configurations of ring resonator vapor sensors...

Fig. 1 Various ring resonator sensor configurations, (a) Microsphere, (b) Silicon-on-insulator planar ring resonator, (c) Slot waveguide ring resonator, (d) Planar disc ring resonator, (e) Glass planar ring array, (f) Microtoroid, (g) Microknot, (h) Opto-fluidic ring resonator (OFRR) and the inset is the SEM image of the OFRR cross-section. Reprinted with permissions from refs [13, 28, 30, 32, 50, 53, 70, 86]...

Ring resonant sensors with different configurations have been demonstrated for label-free detection of a broad range of biomolecules. Discussed in this section are... 

If the dye laser must be used for visible as well as for UV spectroscopy, a daily change of the configuration is troublesome, therefore it is advantageous to apply an extra external ring resonator for frequency doubling [5.236-5.238]. This resonator must, of course, always be kept in resonance with the dye laser wavelength Xi and therefore must be stabilized by a feedback control to the wavelength A.l when the dye laser is tuned. 

A comparative evaluation of the C-n.m.r. data of ten 1-C-aryl-D-glucopyranoses including four pairs of anomers showed that, with the exception of C-4, the carbon atoms of the -pyranose rings resonate at lower fields than do the corresponding carbon atoms of the a-anomers. The configurations at the acetal centres of hexopyranoside 4,6-0-pyruvate acetals [compounds (20)-(25) in... 

The accepted configuration of naphthalene, ie, two fused benzene rings sharing two common carbon atoms in the ortho position, was estabUshed in 1869 and was based on its oxidation product, phthaUc acid (1). Based on its fused-ring configuration, naphthalene is the first member in a class of aromatic compounds with condensed nuclei. Naphthalene is a resonance hybrid ... 

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