Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Impact of Non-Hermiticity and Nonlinear Interactions on
  Disordered-Induced Localized Modes   If disorder-induced Anderson localized states have been observed
experimentally in optics, their study remains challenging leaving a number of
open questions unsolved. Among them, the impact on Anderson localization of
non-Hermiticity, optical gain and loss, and more generally, nonlinearities has
been the subject of numerous theoretical debates, without yet any conclusive
experimental demonstration. Indeed, in systems where localized modes have
reasonable spatial extension to be observed and investigated, their mutual
interaction and coupling to the sample boundaries make it extremely difficult
to isolate them spectrally and investigate them alone. Recently, we
successfully exhibited localized lasing modes individually in an active
disordered medium, using pump-shaping optimization technique. However, a
one-to-one identification of the lasing modes with the eigenmodes of the
passive system was not possible, as the impact of non-Hermiticity and nonlinear
gain on these localized states was unknown. Here, we apply the pump-shaping
method to fully control the non-Hermiticity of an active scattering medium.
  Direct imaging of the light distribution within the random laser allows us to
demonstrate unequivocally that the localized lasing modes are indeed the modes
of the passive system. This opens the way to investigate the robustness of
localized states in the presence of nonlinear gain and nonlinear modal
interactions. We show that, surprisingly, gain saturation and mode competition
for gain does not affect the spatial distribution of the modes.

23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol