Nano Letters,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Nov. 12, 2024
Tunable
terahertz
(THz)
metasurfaces
based
on
optical
control
are
crucial
in
high-speed
communication,
nondestructive
testing,
and
imaging.
However,
realizing
independent
tunability
of
multiple
functions
the
THz
band
remains
challenging
due
to
limitations
materials.
Here,
we
experimentally
demonstrate
a
novel
metasurface
that
employs
two
materials
combined
with
an
electric-field-coupled
inductor
capacitor
microstructure
achieve
all-optical
modulations
amplitude
frequency.
Amplitude
modulation
is
achieved
through
near-infrared
pumping,
reaching
maximum
depth
94.42%.
Broadband
frequency
modulation,
spanning
0.21
THz,
accomplished
using
visible
light
pumping.
The
function
owing
odd-order
nonlinear
polarization
characteristics
perovskite
selective
photon
transition
between
bottom
Si
island
film.
This
work
introduces
approach
for
devices,
offering
valuable
insights
developing
metasurfaces,
intelligent
windows,
multidimensional
ultrafast
switches.
Environmental Technology,
Journal Year:
2025,
Volume and Issue:
unknown, P. 1 - 14
Published: Feb. 16, 2025
To
solve
the
urgent
issue
of
electromagnetic
(EM)
wave
radiation
pollution
and
promote
resource
utilisation
red
mud
(RM,
a
solid
waste),
Fe/C/ceramic
composite
EM
wave-absorbing
materials
were
constructed
by
recycling
RM
with
raw
coal
(RC)
through
simple
mechanical
mixing
then
carbothermal
reduction
between
Fe2O3
in
carbon
component
RC.
It
was
found
that
calcined
temperature
900
°C
can
be
considered
optimal
formation
for
Fe.
In
addition,
tuneable
absorption
performance
could
attained
regulating
mass
ratio
RC
to
(denoted
as
MRC:MRM).
When
MRC:MRM
value
reaches
0.4:1
0.5:1,
composites
exhibit
more
favourable
performance.
The
showed
minimum
reflection
loss
(RLmin)
−41.6
dB,
accompanied
an
effective
bandwidth
(EAB)
3.2
GHz
when
simulating
thickness
2
mm.
0.5:1
possessed
maximum
EAB
4.2
RLmin
−25.3
dB
at
1.5
satisfactory
profits
from
good
impedance
matching
strong
intrinsic
attenuation
capability.
former
attributed
regulatable
parameters
multicomponent
system;
latter
is
mainly
credited
dielectric
arising
medium
graphitised
carbon,
highly
crystalline
Fe,
plentiful
defects
interfaces
composites.
This
work
not
only
provides
valid
path
realise
economical
preparation
microwave
absorbents
but
also
achieves
rational
disposal
RM.
Small,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 20, 2025
Abstract
The
irreconcilable
camouflage
mechanisms
of
radar
and
infrared
spectroscopy
present
substantial
challenges
to
integrating
multi‐physics
field
cloaking
technology.
Although
aerogels
possess
both
microwave
dissipation
thermal
insulation,
higher
emissivity
restrict
further
amelioration
in
compatible
stealth
field.
Herein,
we
propose
a
bilayer
configuration
comprised
aramid
nanofiber
(ANF)
aerogel
shielding
meta‐surface
(ISM).
top
ISM
with
low‐pass
filtering
capabilities
is
engineered
regulate
while
remaining
transparent
microwaves.
While
the
bottom
quaternary
ANF
insulation
are
synthesized
by
multi‐scale
design
strategy
heterogeneous
surface
engineering.
Through
theoretical
experimental
optimization,
assembled
composite
achieves
near‐perfect
absorption
X‐band,
synergy
low
facilitates
concealment
windows.
Specifically,
minimum
reflection
loss
(RL)
reaches
−32.44
dB,
effective
bandwidth
(EAB)
expands
3.69
GHz
(8.71–12.40
GHz),
integration
value
(
ΔH
)
increases
9.92
dB
mm
−1
.
Additionally,
conductivity
(0.0288
W
(m
K)
average
(0.23
3–5
µm
0.25
8–14
µm)
can
reduce
radiation
energy
68.1%.
This
research
provides
new
thought
for
multispectral
demonstrates
enormous
potential
technologies.
