Absorbing waveguides

This convention is also valid for absorbing waveguides, when the refractive-index profile n (x, y) is complex. Absorbing waveguides are discussed later in the chapter. 

Table 11-2 Propagation on absorbing waveguides. Superscripts r and i denote real and imaginary parts, and Re denotes real part. For slightly absorbing waveguides the fields in the expression for y can be approximated by the fields of the nonabsorbing waveguide.

If the real and imaginary parts of (x, y) have the same spatial dependence, i.e. n / is constant, then V, In n = V, In ( ). Consequently, if dp is known for the nonabsorbing waveguide with real profile n, then the complex value of dp for the absorbing waveguide is given by the same expression provided P is everywhere replaced by P + iP as is clear from Eq. (13-11). 

A description of propagation on absorbing waveguides or fibers was given in Chapter 11. When absorption is slight, we can treat the absorbing fiber as a perturbation of the nonabsorbing fiber. Here we consider clad fibers of arbitrary cross-section on which... 

When the applied magnetic field is swept to bring the sample into resonance, MW power is absorbed by the sample. This changes the matching of the cavity to the waveguide and some power is now reflected and passes via the circulator to the detector. This reflected radiation is thus the EPR signal. 

Dasgupta PK, Genfa Z, Poruthoor SK, et al. 1998. High sensitivity gas sensors based on gas permeable liquid core waveguides and long-path absorbance detection. Submitted to Analytical Chemistry. 

B, where A is the absorbance as shown in Figure 2.96. The microwaves emitted by the Klystron tube travel down a waveguide to the epr cavity, in which is positioned the electrochemical cell. The characteristics of the waveform set up in the cavity are a function of its geometry. For the flat, rectangular... 

Fig. 4 Waveguide evanescent wave (EW) principle. Light is propagated through the waveguide (n ) and an electromagnetic field (called EW) is generated in the external medium (n2). The EW interacts with immobilized molecules that absorb energy, leading to attenuation in the reflected light of the waveguide...

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