Artículo de revista
Nonlinear multicore waveguiding structures with balanced gain and loss
Fecha
2015Registro en:
Physical Review A 91, 023822 (2015)
1050-2947
DOI: 10.1103/PhysRevA.91.023822
Autor
Martínez, Alejandro
Molina Gálvez, Mario
Turitsyn, Sergei
Kivshar, Yuri
Institución
Resumen
We study existence, stability, and dynamics of linear and nonlinear stationary modes propagating in radially
symmetric multicore waveguides with balanced gain and loss.We demonstrate that, in general, the system can be
reduced to an effective PT -symmetric dimer with asymmetric coupling. In the linear case, we find that there exist
two modes with real propagation constants before an onset of the PT -symmetry breaking while other modes
have always the propagation constants with nonzero imaginary parts. This leads to a stable (unstable) propagation
of the modes when gain is localized in the core (ring) of the waveguiding structure. In the case of nonlinear
response, we show that an interplay between nonlinearity, gain, and loss induces a high degree of instability,
with only small windows in the parameter space where quasistable propagation is observed. We propose a novel
stabilization mechanism based on a periodic modulation of both gain and loss along the propagation direction
that allows bounded light propagation in the multicore waveguiding structures.