Nonlinearity-induced anomalous mode collapse and nonchiral asymmetric mode switching around multiple exceptional points

Exceptional points and asymmetric mode conversion in quasi-guided dual-mode optical waveguides

Non-Hermitian systems host unconventional physical effects that be used to design new optical devices. We study a non-Hermitian system consisting of 1D planar optical waveguides with suitable amount of simultaneous gain and loss. The parameter space contains an exceptional point, which can be accessed by varying the transverse gain and loss profile. When light propagates through the waveguide s...

Mode Switching

In many control applications, a speciic set of output tracking controllers of satisfactory performance have already been designed and must be used. When such a collection of control modes is available, an important problem is to be able to accomplish a variety of high level tasks by appropriately switching between the low-level control modes. In this paper, we deene a concept of control modes, ...

Fano profiles in scattering around exceptional points

In a previous paper it has been shown that the interference of the first and second order pole of the Green’s function at an exceptional point, as well as the interference of the first order poles in the vicinity of the exceptional point, gives rise to asymmetric scattering cross section profiles. In the present paper we demonstrate that these line profiles are indeed well described by the Beut...

Interaction of nonlinearity and polarization mode dispersion

The derivation of the coupled nonlinear Schrödinger equation and the Manakov-PMD equation is reviewed. It is shown that the usual scalar nonlinear Schrödinger equation can be derived from the Manakov-PMD equation when polarization mode dispersion is negligible and the signal is initially in a single polarization state as a function of time. Applications of the Manakov-PMD equation to studies of...

Protection Switching ( APS ) Mode