By precisely controlling the loss rate and the coupling strength in an open magnonic cavity, the first experimental demonstration in general pseudo-Hermitian systems of two different singularities with nonreciprocity and selectivity has been achieved. One of the singularities is the exceptional point (EP), for which we have innovatively proposed and experimentally realized the case of a nonreciprocal single EP. The experimental phenomenon of coherent and dissipative couplings occurs simultaneously in the case of a nonreciprocal single EP. The theoretical results show distinct mode switching and topological properties for different directions by encircling an EP. Another singularity is the bound state in the continuum (BIC), where we have achieved a nonreciprocal BIC dominated by the dissipative coupling. Our results demonstrate that the planar cavity with both the standing and traveling waves can be an ideal magnonic polariton platform to study pseudo-Hermitian physics.

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• Bound states in the continuum
• Cavity magnonics
• Magnetism
• Magnons
• Non-reciprocal propagation
• Exceptional points
• Non-Hermitian systems
• Cavity resonators
• Ferromagnetic resonance