The Journal of Physical Chemistry Letters,
Год журнала:
2021,
Номер
12(50), С. 12119 - 12128
Опубликована: Дек. 16, 2021
A
novel
methodology
for
direct
modeling
of
long-time
scale
nonadiabatic
dynamics
in
extended
nanoscale
and
solid-state
systems
is
developed.
The
presented
approach
enables
forecasting
the
vibronic
Hamiltonians
as
a
function
time
via
machine-learning
models
trained
directly
domain.
use
periodic
aperiodic
functions
that
transform
into
effective
input
modes
artificial
neural
network
demonstrated
to
be
essential
such
an
work
both
abstract
atomistic
models.
best
strategies
possible
limitations
pertaining
new
are
explored
discussed.
An
exemplary
simulation
unprecedentedly
long
20
picosecond
trajectories
conducted
divacancy-containing
monolayer
black
phosphorus
system,
importance
conducting
simulations
demonstrated.
New
insights
excited
states
photophysics
this
system
presented,
including
role
decoherence
model
definition.
npj Computational Materials,
Год журнала:
2024,
Номер
10(1)
Опубликована: Апрель 18, 2024
Two-dimensional
(2D)
materials
combine
many
fascinating
properties
that
make
them
more
interesting
than
their
three-dimensional
counterparts
for
a
variety
of
applications.
For
example,
2D
exhibit
stronger
electron-phonon
and
electron-hole
interactions,
energy
gaps
effective
carrier
masses
can
be
easily
tuned.
Surprisingly,
published
band
several
obtained
with
the
$GW$
approach,
state-of-the-art
in
electronic-structure
calculations,
are
quite
scattered.
The
details
these
such
as
underlying
geometry,
starting
point,
inclusion
spin-orbit
coupling,
treatment
Coulomb
potential
critically
determine
how
accurate
results
are.
Taking
monolayer
MoS$_2$
representative
material,
we
employ
linearized
augmented
planewave
+
local
orbital
method
to
systematically
investigate
all
aspects
affect
quality
$G_0W_0$
also
provide
summary
literature
data.
We
conclude
best
overall
agreement
experiments
coupled-cluster
calculations
is
found
HSE06
point
including
truncated
potential,
an
analytical
singularity
at
$q=0$.
npj Computational Materials,
Год журнала:
2025,
Номер
11(1)
Опубликована: Янв. 11, 2025
Metal
halide
perovskites
(MHPs)
exhibit
unusual
properties
and
complex
dynamics.
By
combining
ab
initio
time-dependent
density
functional
theory,
nonadiabatic
molecular
dynamics
machine
learning,
we
advance
quantum
simulation
to
nanosecond
timescale
demonstrate
that
large
fluctuations
of
MHP
defect
energy
levels
extend
light
absorption
longer
wavelengths
enable
trapped
charges
escape
into
bands.
This
allows
low
photons
contribute
photocurrent
through
up-conversion.
Deep
can
become
shallow
transiently
vice
versa,
altering
the
traditional
classification
deep.
While
fluctuate
more
in
MHPs
than
semiconductors,
some
levels,
e.g.,
Pb
interstitials,
remain
far
from
band
edges,
acting
as
charge
recombination
centers.
Still,
many
defects
deemed
detrimental
based
on
static
structures,
are
fact
benign
The
extended
harvesting
up-conversion
provide
strategies
for
design
novel
solar,
optoelectronic,
information
devices.
ACS Photonics,
Год журнала:
2021,
Номер
8(9), С. 2770 - 2780
Опубликована: Авг. 31, 2021
The
exciton–exciton
annihilation
(EEA)
process
easily
occurs
in
monolayer
transition
metal
dichalcogenides
(TMDs)
because
of
the
strong
Coulomb
interaction
and
quantum
confinement
effect,
which
enhance
many-body
excitons.
This
can
affect
performance
optoelectronic
devices.
It
is
crucial
to
examine
effect
defect
states
on
EEA
determine
whether
it
comparable
that
at
low
excitation
intensities,
particularly
when
applied
laser
devices
a
high
exciton
density.
In
this
study,
femtosecond
transient
absorption
spectroscopy
was
used
explore
four
types
CVD-grown
TMDs
(i.e.,
WS2,
WSe2,
MoS2,
MoSe2).
We
demonstrated
defect-assisted
local
excitons
enhanced
plays
key
role
relaxation
densities
approximately
1012
cm–2
below
Mott
density
1013
cm–2.
measured
rates
for
MoSe2,
MoS2
were
0.016,
0.026,
0.049,
0.102
cm2/s,
respectively,
implying
as
increase
TMDs.
Our
results
provide
profound
insight
into
densities.
The Journal of Physical Chemistry Letters,
Год журнала:
2022,
Номер
13(34), С. 7898 - 7905
Опубликована: Авг. 18, 2022
In
search
of
an
efficient
solar
energy
harvester,
we
herein
performed
a
time
domain
density
functional
study
coupled
with
nonadiabatic
molecular
dynamics
(NAMD)
simulation
to
gain
atomistic
insight
into
the
charge
carrier
graphitic
carbon
nitride
(g-CN)-tungsten
telluride
(WTe2)
van
der
Waals
heterostructure.
Our
NAMD
predicted
ultrafast
electron
(589
fs)
and
hole-transfer
(807
in
g-CN/WTe2
heterostructure
delayed
electron-hole
recombination
process
(2.404
ns)
as
compared
that
individual
g-CN
(3
ps)
WTe2
(0.55
monolayer.
The
transfer
is
due
strong
electron-phonon
coupling
during
charge-transfer
while
comparatively
weak
coupling,
sufficient
band
gap,
lower
(NAC),
fast
decoherence
slow
down
process.
results
exciton
relaxation
are
valuable
for
insightful
understanding
designing
photovoltaic
devices
based
on
organic-inorganic
2D
heterostructures.
Physical review. B./Physical review. B,
Год журнала:
2022,
Номер
105(8)
Опубликована: Фев. 24, 2022
Spin-orbit
coupling
(SOC),
which
can
induce
spin
flip
during
the
relaxation
of
photoexcited
charge
carrier,
plays
a
crucial
role
in
dynamics.
In
this
work,
we
have
used
time-domain
ab
initio
nonadiabatic
molecular
dynamics
(NAMD)
method
to
study
SOC
induced
ultrafast
demagnetization
Ni
at
$300\phantom{\rule{0.16em}{0ex}}\mathrm{K}$.
The
spin-diabatic
representation
using
spin-polarized
Kohn-Sham
(KS)
basis
sets
and
spin-adiabatic
spinor
been
applied,
both
them
achieve
with
timescale
around
$100\phantom{\rule{0.16em}{0ex}}\mathrm{fs}$.
suggests
picture
that
electron-phonon
(EPC)
provides
direct
energy
channel
among
same-spin
states,
while
flip.
After
photoexcitation,
it
is
found
spin-minority
electrons
relax
states
rather
than
opposite-spin
since
EPC
larger
by
one
order
magnitude.
By
contrast,
for
spin-majority
electrons,
occurs
there
are
no
empty
as
electron
acceptor
above
Fermi
level.
different
pathways
demagnetization.
an
Elliott-Yafet
spin-phonon
scattering
picture.
reduction
magnetic
moment
may
magnon
drive
further
NAMD
simulation
critical
angle
understand
how
affect
process
Ni.
ACS Nano,
Год журнала:
2023,
Номер
17(15), С. 14253 - 14282
Опубликована: Июль 17, 2023
The
coupled
interactions
among
the
fundamental
carriers
of
charge,
heat,
and
electromagnetic
fields
at
interfaces
boundaries
give
rise
to
energetic
processes
that
enable
a
wide
array
technologies.
energy
transduction
these
results
in
thermal
dissipation
surfaces,
often
quantified
by
boundary
resistance,
thus
driving
functionalities
modern
nanotechnologies
are
continuing
provide
transformational
benefits
computing,
communication,
health
care,
clean
energy,
power
recycling,
sensing,
manufacturing,
name
few.
It
is
purpose
this
Review
summarize
recent
works
have
been
reported
on
ultrafast
nanoscale
heat
transfer
mechanisms
across
when
different
couple
near
or
interfaces.
We
review
solids,
liquids,
gasses,
plasmas
drive
resulting
interfacial
temperature
gradients
due
momentum
coupling
various
combinations
electrons,
vibrons,
photons,
polaritons
(plasmon
phonon
polaritons),
molecules.
These
transport
with
involve
relatively
research,
thus,
several
opportunities
exist
further
develop
nascent
fields,
which
we
comment
throughout
course
Review.
Nano Letters,
Год журнала:
2023,
Номер
23(15), С. 7029 - 7036
Опубликована: Июль 26, 2023
Quantum
simulations
of
photoexcited
low-dimensional
systems
are
pivotal
for
understanding
how
to
functionalize
and
integrate
novel
two-dimensional
(2D)
materials
in
next-generation
optoelectronic
devices.
First-principles
predictions
extremely
challenging
due
the
simultaneous
interplay
light–matter,
electron–electron,
electron–nuclear
interactions.
We
here
present
an
advanced
ab
initio
many-body
method
that
accounts
quantum
coherence
non-Markovian
effects
while
treating
electrons
nuclei
on
equal
footing,
thereby
preserving
fundamental
conservation
laws
like
total
energy.
The
impact
this
advancement
is
demonstrated
through
real-time
complex
multivalley
dynamics
a
molybdenum
disulfide
(MoS2)
monolayer
pumped
above
gap.
Within
single
framework,
we
provide
parameter-free
description
coherent-to-incoherent
crossover,
elucidating
role
microscopic
collective
excitations
dephasing
thermalization
processes.
Nature Communications,
Год журнала:
2023,
Номер
14(1)
Опубликована: Янв. 6, 2023
Fano
resonance
which
describes
a
quantum
interference
between
continuum
and
discrete
states,
provides
unique
method
for
studying
strongly
interacting
physics.
Here,
we
report
dark
excitons
zone-edged
acoustic
phonons
in
few-layer
WS2
by
using
the
resonant
Raman
technique.
The
with
large
momentum
at
M-point
of
Brillouin
zone
exciton
states
related
to
optically
forbidden
transition
K
Q
valleys
are
coupled
exciton-phonon
interactions.
We
observe
rich
behaviors
across
layers
modes
defined
an
asymmetry-parameter
q:
including
constructive
two
mirrored
asymmetry
peaks
(weak
coupling,
q
>
1
<
-
1),
destructive
dip
(strong
∣q∣
1).
Our
results
provide
new
insight
into
two-dimensional
semiconductors,
where
such
interferences
play
key
role
their
transport,
optical,
thermodynamic
properties.
Nano Letters,
Год журнала:
2024,
Номер
24(26), С. 8117 - 8125
Опубликована: Июнь 20, 2024
Transition
metal
dichalcogenides
(TMDs)
are
quantum
confined
systems
with
interesting
optoelectronic
properties,
governed
by
Coulomb
interactions
in
the
monolayer
(1L)
limit,
where
strongly
bound
excitons
provide
a
sensitive
probe
for
many-body
interactions.
Here,
we
use
two-dimensional
electronic
spectroscopy
(2DES)
to
investigate
and
their
dynamics
1L-WS