A. Padrón-Godínez | Searcharxiv

arXiv2021

Unidirectional reflectivity in non-Hermitian lossy thin films

Inspired by non-Hermitian systems, we study reflection and transmission in a stack of thin films composed by the repetition of a bipartite unit cell. We aim for controlled reflection and transmission using lossless and lossy materials in order to develop an optical diode to generate entanglement photons source. Particularly, we show unidirectional reflection using transfer matrix methods and confirm our results by finite element simulation.

physics.optics↗

arXiv2020

Lasing in para-Fermi class-B microring resonator arrays

We demonstrate lasing in arrays of microring resonators with underlying para-Fermi symmetry. The properties of the algebra allow the analytic prediction of propagation constants and normal modes of an array of passive resonators that show the optical analogue of a zero-energy mode that is its own chiral pair. The rest of the normal modes in the linear model form chiral pairs that are evenly distributed around the pseudo zero-energy mode. We use this information to construct a class-B laser model where even and odd sites are driven with different strength in a pattern following para-Fermi algebra chirality to demonstrate lasing with enhancement or suppression of the zero-energy mode. Zero-energy mode lasing is stable to initial conditions for a large set of driving ratios. Lasing with zero-energy mode suppression is unstable and more susceptible to initial field configurations.

physics.optics↗