TIME-DOMAIN LEAKY MODES ON LAYERED MEDIA - DISPERSION CHARACTERISTICS AND SYNTHESIS OF PULSED RADIATION

In a recent comprehensive study of short-pulse radiation from current elements in the presence of plane layered dielectric media, various alternatives have been explored for constructing the transient field in terms of spectral-domain wave functions. Two distinctive synthesis options have been structured around conventional time-harmonic and nonconventional time-dependent basis wave functions, respectively. To understand the characteristic properties of each, it is necessary to explore in detail the frequency-wavenumber dispersion relation for the layered environment. Especially interesting is the behavior of the nonconventional time-domain leaky modes which exhibit anomalies not encountered in their conventional time-harmonic counterparts. An example is given of how these time-domain modal basis fields synthesize highly resolved short-pulse radiation from a source in a dielectric layer.