Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coherently time-varying metasurfaces   Known coherent metasurfaces control interference of waves of a given
frequency with other coherent waves at the same frequency, either illuminating
from a different direction or created as intermodulation products. In this
paper, we introduce a class of metasurfaces that are modulated in time
coherently with the illuminating radiation. Importantly, such modulation opens
a possibility to control reflection, absorption, and transmission at multiple
frequencies, including illuminations by two or more incoherent waves. In
particular, we study dynamic resistive layers and show how to use them to
design multi-frequency perfect absorbers that overcome the bandwidth limit for
static linear absorbers. Furthermore, we demonstrate possibilities of remote
tuning of the absorption level. We hope that this work opens up novel avenues
in wave engineering using coherent modulation of metasurface parameters.

37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th