Photonics,
Journal Year:
2024,
Volume and Issue:
11(12), P. 1148 - 1148
Published: Dec. 6, 2024
Temperature
sensors
play
important
roles
in
wide-spreading
human
activities.
The
non-contact
method
of
using
temperature
offers
significant
advantages
but
faces
challenges
detection
precision.
In
this
work,
a
double-layer
asymmetric
terahertz
(THz)
metamaterial
combined
with
phase
transition
oxide
was
proposed
to
realize
sensor
high
sensitivity.
exhibited
band-stop
filtering
effects
the
simulated
transmission
spectra.
changes
induced
reversible
VO2,
resulting
altered
conductivity.
numerical
results
indicated
that
S21
parameter
increases
from
−44.33
dB
−4.78
at
frequency
1.22
THz
as
conductivity
VO2
film
10
5000
S/m,
achieving
modulation
depth
89%.
addition,
86
nm
thick
underwent
range
54.93
°C
66.93
°C,
sensitivity
1.82
dB/°C
for
sensing.
This
work
provided
great
insights
into
development
metamaterials
based
on
high-precision
measurement.
Scientific Reports,
Journal Year:
2025,
Volume and Issue:
15(1)
Published: Jan. 17, 2025
A
novel
helically
twisted
photonic
crystal
fiber
(PCF)
is
designed
and
proposed
for
sensing
toxic
gases
with
refractive
indices
ranging
from
1.00
to
1.08.
The
PCF
consists
of
twelve
hollow
pipes
arranged
circularly
around
the
core
support
THz
radiation
propagation.
Low-loss
polymer
Topas
used
as
background
material
cladding.
360°
over
50
cm
enhance
anti-resonance
in
region.
fundamental
LP01
mode
analyzed
using
finite-difference
eigenmode
(FDE)
method.
sensor
operates
across
four
frequency
bands
(0.2
3.0
THz)
minimal
transmission
loss
(~
10⁻⁴
1/cm).
Key
parameters
such
index
sensitivity,
relative
resolution,
figure
merit
(FOM)
are
evaluated.
average
sensitivities
1450,
2250,
3000,
2550
Bands
1
4,
respectively,
100%
sensitivity
all
bands.
detects
changes
small
10⁻⁴.
FOM,
defined
inverse
full
width
at
half
maximum,
exceeds
30
1/RIU,
reaching
up
250
1/RIU
due
sharp
resonance
peaks.
Compared
other
sensors,
this
design
offers
enhanced
performance
like
SOx,
NOx,
CO,
while
maintaining
a
simple
structure.
Sensors,
Journal Year:
2025,
Volume and Issue:
25(2), P. 507 - 507
Published: Jan. 16, 2025
This
research
proposes
an
all-metal
metamaterial-based
absorber
with
a
novel
geometry
capable
of
refractive
index
sensing
in
the
terahertz
(THz)
range.
The
structure
consists
four
concentric
diamond-shaped
gold
resonators
on
top
metal
plate;
increase
height
by
2
µm
moving
from
outer
to
inner
resonators,
making
design
distinctive.
configuration
has
played
very
significant
role
achieving
multiple
ultra-narrow
resonant
absorption
peaks
that
produce
high
sensitivity
when
employed
as
sensor.
Numerical
simulations
demonstrate
it
can
achieve
six
within
frequency
range
5
8
THz.
sensor
maximum
absorptivity
99.98%
at
6.97
proposed
also
produces
high-quality
factors
each
resonance.
average
is
7.57/Refractive
Index
Unit
(THz/RIU),
which
significantly
compared
current
state
art.
instrumental
detecting
smaller
traces
samples
have
correlated
indices,
like
several
harmful
gases.
Hence,
be
used
potential
gas
detector
frequency.
Furthermore,
proves
polarization-insensitive
and
stable
response
angle
incidence
increased
up
60°.
At
wavelength,
for
any
value
aforementioned
angles,
targeting
THz
spectroscopy-based
biomolecular
fingerprint
detection
energy
harvesting
applications.
Abstract
Spoof
localized
surface
plasmons
(spoof
LSPs,
SLSPs)
have
recently
emerged
as
high‐quality‐factor
(Q‐factor)
multipole
electromagnetic
resonant
structures,
showcasing
considerable
promise
in
the
field
of
sensing.
However,
sensing
terahertz
band
presents
notable
challenges.
Here,
a
dual‐port
coupled
SLSPs
resonator
and
single‐port
are
proposed
with
phase
separated
excitation,
both
exhibiting
high‐Q‐factors
band.
The
can
sustain
odd
resonance
mode
even
mode,
whereas
generate
vortex
wave
modes
asymmetric
modes.
In
measurement,
highest
Q
value
is
69
at
frequency
179.4
GHz.
Equally
noteworthy
resonator,
which
reaches
groundbreaking
Q‐factor
405.4
150
GHz,
marking
significant
advancement
Q‐factors
passive
devices.
Biosensing
for
Bletilla,
Fritillaria,
Rhubarb,
glucose
implemented,
maximum
shift
15.8
GHz
7.8
SLSPs.
figures
merits
(FoM)
4.1
12.9RIU
−1
dual‐
resonators,
respectively,
underscoring
substantial
potentials
this
work
realm
Advanced Optical Materials,
Journal Year:
2025,
Volume and Issue:
unknown
Published: May 10, 2025
Abstract
Terahertz
(THz)
waves
offer
large
bandwidth
with
less
interference
and
provide
detailed
information
on
materials
in
a
non‐destructive
manner,
making
them
valuable
for
wireless
communication,
security
screening,
biomedical
identification.
Despite
the
growing
significance,
demand
high‐performance
ultra‐broadband
THz
detectors
remains
unmet
current
limitations.
In
this
paper,
we
propose
high‐sensitivity
broadband
detector
utilizing
semimetal
TaFe
1.25
Te
3
,
leveraging
its
gapless
electron
excitation
under
illumination
fast
carrier
dynamics
through
photothermoelectric
effect
at
room
temperature.
The
presents
response
speed
of
11.1/5.6
µs,
responsivity
7.58
V
W
−1
noise‐equivalent
power
(NEP)
156
pW/Hz
1/2
0.1
THz.
By
incorporating
graphene
within
van
der
Waals
heterostructure,
self‐powered
is
dramatically
enhanced
by
an
order
magnitude.
/graphene
features
extended
up
to
0.3
THz,
improved
279.15
lower
NEP
9
thanks
efficient
energy
transfer
optimized
characteristics
asymmetry
architecture.
Our
research
deepens
understanding
ultrafast
hot
offers
promising
approach
manipulate
response,
advancing
their
functionality
versatility
practical
applications.
