Controlling waveguide modes using PT transformation media

Abstract

We study rectangular waveguide modes loaded with parity-time (PT ) transformation media derived bycomplex transformation optics (CTO) approach. PT transformation media are obtained through mirror symmetriccomplex coordinate transformations resulting in a balanced loss/gain media. It is shown that waveguide modes can becontrolled by simply changing the imaginary part of the complex coordinate transformation while not affecting any othercharacteristic of the waveguide. The field distribution inside the waveguide can either be stretched towards the sides orsqueezed at the center of the waveguide by employing different loading configurations.