arXiv subjects

J. R. Silva

Publications and source records attributed to J. R. Silva.

3 recordsLinked to original sources

arXiv2026

Spectral Distribution of Exceptional Points in Lattices with Localized Loss

We explore the existence and stability of exceptional points (EPs) in finite waveguide arrays subject to single-site dissipation. We show that the EP landscape is dictated by a geometry-dependent parity effect, leading to strictly distinct spectral behaviors for arrays with even versus odd numbers of waveguides. Through analytical derivation and numerical analysis, we define the conditions under which these singularities emerge and evolve. Our findings clarify the mechanisms of symmetry breaking in finite non-Hermitian lattices, offering new guidelines for the design of robust optical structures that exploit or avoid exceptional points.

physics.optics↗

arXiv2026

Non-markovian reservoir profile effects on dynamics of light within a single waveguide

In this work, we investigate how different reservoir memory profiles influence the dynamical evolution of a single waveguide coupled to an external environment. We compare three representative memory kernels: Lorentzian, Gaussian and Uniform, highlighting their distinct spatial correlations and their impact on system behavior. We compute the transmission amplitude, transparency properties, as well as long-time behavior of the system under each memory model. To quantify deviations from Markovian dynamics, we employ a non-Markovianity measure based on information backflow, allowing a direct comparison between the structured reservoirs and the Markovian limit. Our results reveal clear signatures of memoryless-induced modifications in the transmission spectrum and demonstrate how specific reservoir profiles enhance or suppress non-Markovian effects.

quant-ph↗

arXiv2025

Anomalous transparency of photons in non-Markovian coupled waveguides

The transmission of photons through a pair of coupled single-mode waveguides is studied in detail. It is assumed that one of the waveguides is coupled to a non-Markovian reservoir, described by a Lorentzian spectrum distribution. We identified four distinct regimes for the transmission coefficient and found that, in some conditions, it is more efficient to launch the photons in the lossy waveguide to achieve high transmission. We also report on a loss-induced transparency effect that is induced by the distribution of the frequencies present in the reservoir.

physics.optics↗