Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two-port multimode interference reflectors based on aluminium mirrors in
  a thick SOI platform   Multimode interference reflectors (MIRs) were recently introduced as a new
type of photonic integrated devices for on-chip, broadband light reflection. In
the original proposal, different MIRs were demonstrated based on total internal
reflection mirrors made of two deep-etched facets. Although simpler to
fabricate, this approach imposes certain limits on the shape of the field
pattern at the reflecting facets, which in turn restricts the types of MIRs
that can be implemented. In this work, we propose and experimentally
demonstrate the use of aluminium-based mirrors for the design of 2-port MIRs
with variable reflectivity. These mirrors do not impose any restrictions on the
incident field, and thus give more flexibility at the design stage. Different
devices with reflectivities between~0~and~0.5 were fabricated in a 3~um thick
SOI platform, and characterization of multiple dies was performed to extract
statistical data about their performance. Our measurements show that, on
average, losses both in the aluminium mirror and in the access waveguides
reduce the reflectivities to about~79\% of their target value. Moreover,
standard deviations lower than $\pm$5\% are obtained over a 20~nm wavelength
range (1540-1560~nm). We also provide a theoretical modelling of the aluminium
mirror based on the effective index method and Fresnel equations in multilayer
thin films, which shows good agreement with FDTD simulations.

30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph