onlinear dynamics and chaos are paradigm examples for complex dynamical behaviour. Quantum chaos, the quantum or wave mechanical treatment of classically chaotic systems, has attracted a lot of interest since the 1990s when electronic and photonic systems provided an experimental platform to realize such ballistic mesoscopic cavities on the micrometer scale, with sizes of several resonance wavelengths. In this talk we will illustrate their complex dynamics in real and phase space using classical and wave simulations, thereby bringing to life the principle of ray-wave correspondence.
In the so-called Limacon cavity chaotic dynamics was shown to enable directed lasing action from microdisk resonators: the unstable manifold, an inherent property of nonlinear dynamics, determines the far-field characteristics and ensures, despite its „chaotic" origin, an universal and robust unidirectional emission. In anisotropic systems, the loss of angular momentum conservation induces complex dynamics with chaotic features even for circular cavity shapes. We will investigate Dirac fermion billiards realized in graphene systems, especially in bilayer graphene where trigonal warping gives rise to preferred propagation directions. For birefringent optical cavities we use transformation optics to reveal their dynamical behaviour and the differences to the usually considered isotropic counterparts.
The intrinsic openness of optical systems implies complex resonance energies, and non-Hermitian effects can occur. We will illustrate their nature in a coupled-microdisk system and briefly point out how exceptional points in parameter space structure the resonance morphology.
The seminar is organized by Department of condensed matter theory