Аннотация
Selecting the quantum signals with respect to features like direction of propagation or impinging energy makes a ubiquitous operation that is employed in a variety of quantum engineering applications. The conditions for optimally selective angular and energy filtering via homogeneous planar inclusions are determined and the derived designs exhibit substantial robustness with respect to fabrication defects. The reported findings may open new uncharted directions towards the efficient design of integrated devices exploiting quantum filtering from sharp sensors and tuners to multiport networks and quantum circuits.