Читать книгу Electromagnetic Metasurfaces - Christophe Caloz - Страница 22

1 1 Each of the four tensors in (2.3) contains susceptibility components, amounting to a total of susceptibilities.

2 2 Note that some materials, such as glass, can often be assumed to be dispersionless within a limited frequency range given the negligible variations of their constitutive parameters across that range.

3 3 Here, the tildes are used to differentiate the time-domain susceptibilities from their frequency-domain counterparts.

4 4 The local field is defined as the total field, at the position of the particle, minus the field produced by the particle itself.

5 5 In the time domain, time reversal consists in replacing the variable by . Therefore, a function becomes . In the frequency domain, the time-reversal operation consists in taking the complex conjugate of the Fourier transform of , i.e. in transforming into , where the plus sign is for a time-even quantity while the minus sign is for a time-odd quantity [28].

6 6 These relations not only provide the usual reciprocity conditions, but also the nonreciprocity conditions [28], e.g. in the case of a magnetic nonreciprocal medium.