Scattering properties of a PT dipole

Electromagnetic response of a PT dipole is studied both analytically and numerically. In the analytical approach, the dipole is represented by two point scatterers. Within the first Born approximation, the asymmetry of the scattering field with respect to the orientation of the dipole is proven. In numerical simulations, the dipole is represented by two infinitely long, parallel cylinders with opposite sign of the imaginary part of a refractive index. Numerical data confirm the validity of the Born approximation in the weak scattering limit, while significant deviations from the Born approximation were observed for stronger scatterers and in the near-field range.