Vortex‐Vector Beam Conversion and Chiral Field Manipulation based on Terahertz Liquid Crystal Cascaded Metadevice
Laser & Photonics Review,
Год журнала:
2024,
Номер
unknown
Опубликована: Июнь 4, 2024
Abstract
Vortex‐vector
beam
generators
can
effectively
improve
the
channel
capacity
and
communication
accuracy,
but
they
face
problems
of
narrow
operating
frequency
band,
low
efficiency,
fixed
function.
Here,
a
terahertz
liquid
crystal
cascaded
metadevice
is
demonstrated,
including
layer,
an
asymmetric
metasurface
helical
phase
layer.
The
combination
crystal's
anisotropy
structural
from
realizes
dynamic
chirality
construction.
Then,
tunable
chiral
fields
are
coupled
with
geometric
last
layer
to
realize
active
control
between
symmetric
spin‐orbit
angular
momentum
coupling,
leading
two
types
generation
conversion:
1)
spin‐dependent
conversion
energy
distribution
vortex
beams
±2
topological
charges;
2)
conversions
2‐order
cylindrical
vector
beam.
experimental
results
show
that
excitation
efficiency
reach
over
92.1%,
intensity
modulation
depth
different
more
than
72.4%.
This
THz
mechanism
device
scheme
increase
degree
freedom
have
potential
applications
in
multi‐channel
wireless
communication,
polarization
multiplexing
imaging,
spectrum
detection.
Язык: Английский
Active control of terahertz quasi-BIC and asymmetric transmission in a liquid-crystal-integrated metasurface
Photonics Research,
Год журнала:
2024,
Номер
12(10), С. 2207 - 2207
Опубликована: Июль 23, 2024
Quasi-bound
states
in
the
continuum
(quasi-BICs)
offer
an
excellent
platform
for
flexible
and
efficient
control
of
light-matter
interactions
by
breaking
structural
symmetry.
The
active
quasi-BIC
device
has
great
application
potential
fields
such
as
optical
sensing,
nonlinear
optics,
filters.
Herein,
we
experimentally
demonstrate
terahertz
(THz)
induced
polarization
conversion
a
liquid
crystal
(LC)-integrated
metasurface,
which
consists
symmetrically
broken
double-gap
split
ring
resonator
(DSRR),
LC
layer,
double
graphite
electrodes.
In
process
orientation
under
external
field,
realizes
from
OFF
state
to
ON
state.
state,
no
effect,
behaves
non-resonant
state;
but
exhibits
obvious
resonance.
Furthermore,
achieve
asymmetric
transmission
based
on
polarization-induced
modulation
precisely
at
resonance
position,
its
isolation
can
be
controlled
field.
study
dynamic
LC-integrated
metasurface
introduces
very
promising
route
THz
devices,
guarantees
applications
communications,
switching,
sensing
systems.
Язык: Английский
Tri-band terahertz polarization reconfigurable reflective metasurface based on liquid crystal
Applied Physics Letters,
Год журнала:
2025,
Номер
126(7)
Опубликована: Фев. 17, 2025
Terahertz
technology
is
poised
to
revolutionize
next-generation
wireless
communication
systems,
such
as
5G-A
and
6G,
by
addressing
the
growing
need
for
efficient
electromagnetic
wave
modulation
in
terahertz
frequency
band.
In
this
study,
we
present
a
reflective
metasurface
comprising
dual
metal
layers
tunable
liquid
crystal
medium,
designed
achieve
dynamic
linear-to-circular
polarization
conversion.
Experimental
results
demonstrate
conversion
across
three
bands:
248–254,
265–278,
287–292
GHz.
Furthermore,
left-hand
circular
(LHCP)-to-right-hand
(RHCP)
switching
achieved
at
248–254
GHz,
with
stable
RHCP
state
observed
265–278
These
findings
validate
device's
ability
dynamically
control
states
through
applied
bias
voltage.
By
enabling
precise
flexible
modulation,
provides
scalable
solution
reconfigurable
intelligent
surfaces,
paving
way
advanced
systems
future
networks.
Язык: Английский
Mirror-symmetric multi-OAM vortex beam generation with 1-bit interleaved terahertz metasurfaces
Optics & Laser Technology,
Год журнала:
2025,
Номер
186, С. 112606 - 112606
Опубликована: Фев. 27, 2025
Язык: Английский
Terahertz active multi-channel vortices with parity symmetry breaking and near/far field multiplexing based on a dielectric-liquid crystal-plasmonic metadevice
Opto-Electronic Advances,
Год журнала:
2025,
Номер
0(0), С. 240250 - 240250
Опубликована: Янв. 1, 2025
Язык: Английский
Active Broadband Terahertz OAM‐Based Metalens Based on Multi‐Channel Multiplexing
Laser & Photonics Review,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 8, 2025
Abstract
Vortex
beams
with
orbital
angular
momentum
(OAM)
exhibit
immense
potential
in
various
fields
such
as
communications,
information
processing,
and
optical
tweezers.
Nevertheless,
current
terahertz
vortex
beam
generators
still
face
challenges
including
narrow
frequency
bands,
low
efficiency,
limited
multiplexing
capabilities,
difficulties
dynamic
tuning.
Here,
the
study
introduces
a
new
electrically
controlled
multi‐channel
strategy
that
harnesses
cascaded
helical
geometric
metasurface,
liquid
crystal
(LC)
layer,
OAM‐based
metalens
to
achieve
comprehensive
independent
phase
manipulation
across
all
four
spin
channels.
Moreover,
by
employing
spin,
spatial,
OAM
multiplexing,
LC
active
control
technology,
eight
distinguishable
(SAM)‐OAM
coupling
states
are
decoded,
enabling
of
6
different
topological
charges.
Experimental
validation
reveals
remarkable
performance:
within
broadband
range
0.4–0.6
THz,
peak
excitation
efficiency
up
94%,
each
mode
purity
reaching
its
highest
level
>80%,
minimum
value
inter‐mode
crosstalk
is
<–11
dB.
This
generation
conversion
mechanism
enhances
operational
flexibility
light
field
manipulation,
breaking
through
limitations
channel
band,
pioneering
novel
avenue
for
bolstering
parallel
mitigating
inter‐channel
crosstalk.
Язык: Английский
Efficient Manipulation of Near‐Field Terahertz Waves: Individually Addressable Transmissive Meta‐Device
Laser & Photonics Review,
Год журнала:
2024,
Номер
unknown
Опубликована: Июль 22, 2024
Abstract
Due
to
the
powerful
capability
in
manipulating
electromagnetic
(EM)
waves,
digital
coding
and
programmable
metasurfaces
have
found
vast
application
prospects
across
numerous
areas
such
as
next‐generation
wireless
communications
holography.
Liquid
crystals
(LCs),
dielectric
materials
with
significant
birefringence
effect
over
a
wide
frequency
range,
provide
cost‐effective
solution
for
achieving
flexible
EM
manipulations,
especially
terahertz
(THz)
band.
Different
from
conventional
1D
control
single
functionality
of
transmissive
LC‐based
devices,
here,
16
×
addressable
amplitude‐phase
meta‐device
is
proposed
support
multiplexing
by
using
film
on
glass
(FOG)
technology.
Both
numerical
simulations
experimental
results
demonstrate
that
meta‐atom
exhibits
an
amplitude
modulation
depth
90%
phase
tuning
range
≈180°
at
two
distinct
frequencies,
hence
can
multifunctional
applications,
including
near‐field
printing
imaging,
3D
THz
energy
convergence,
zero‐order
Bessel
beam
generation.
The
strategy
paves
way
constructing
highly
integrated
high‐performance
information
processing
systems.
Язык: Английский
Terahertz bandpass and bandstop filter based on the Babinet complementary metamaterials
Optics Communications,
Год журнала:
2024,
Номер
571, С. 130944 - 130944
Опубликована: Авг. 3, 2024
Язык: Английский
Making liquid crystals twitch under metamaterial-enhanced terahertz illumination: toward strong optical nonlinearity
Optics Express,
Год журнала:
2024,
Номер
33(1), С. 1008 - 1008
Опубликована: Дек. 27, 2024
We
provide
the
first
direct
experimental
evidence
for
reorientation
of
liquid
crystals
by
polarized
radiation
from
a
conventional,
low
power,
oscillator-based
terahertz
time-domain
spectrometer.
Using
pump
-
optical
probe
setup,
we
observed
that
occurs
locally
through
resonant
amplification
field
in
specially
designed
planar
metamaterial,
adjacent
to
crystal
layer,
and
increases
with
increasing
incident
intensity.
Our
work
thus
demonstrates
it
is
possible
induce
strong
nonlinearity
part
spectrum,
paving
way
toward
development
new
all-optical
active
devices
as
well
electric
sensors
localized
systems.
Язык: Английский