Optics Express,
Год журнала:
2024,
Номер
32(17), С. 29549 - 29549
Опубликована: Июнь 24, 2024
In
this
paper,
we
present
a
laser
source
designed
specifically
for
time-
and
angle-resolved
photoemission
spectroscopy
(TR-ARPES)
investigations
of
light-induced
electron
dynamics
in
quantum
materials.
Our
is
based
on
ytterbium-doped
that
seeds
an
optical
parametric
amplifier
(OPA)
followed
by
difference
frequency
generation
(DFG)
stage.
This
configuration
enables
the
tunable
near-infrared
mid-infrared
pulses
(1.5
to
8
μm
-
0.82
0.15
eV)
at
250
kHz
repetition
rate,
serving
as
pump
TR-ARPES
measurements.
The
remaining
energy
used
generate
ultraviolet
6
eV
probe
pulses,
which
prompt
material
emit
photoelectrons.
We
demonstrate
long-term
stability
source,
well
characterization
beam
profiles
pulse
durations.
Additionally,
preliminary
results
obtained
Bi
2
Te
3
,
prototypical
3D
topological
insulator.
paper
illustrates
capability
our
electronic
Reviews of Modern Physics,
Год журнала:
2024,
Номер
96(1)
Опубликована: Фев. 27, 2024
Time-resolved
angle-resolved
photoemission
spectroscopy
provides
access
to
light-induced
changes
in
the
electronic
band
structure
and
interactions
of
solids,
out-of-equilibrium
electron
dynamics.
This
article
reviews
history
future
prospects
for
development
technique,
offers
an
overview
recent
achievements
studying
unoccupied
light-driven
states,
photoinduced
phase
transitions,
electron-phonon
scattering,
dynamics
quantum
materials,
including
topological
insulators,
unconventional
superconductors,
traditional
novel
semiconductors,
excitonic
spin-textured
systems.
Recent
breakthroughs
in
high
repetition-rate
extreme
ultraviolet
(XUV)
light
sources
and
photoelectron
analyzers
have
led
to
dramatic
advances
the
performance
of
time-resolved
photoemission
experiments.
In
this
perspective
article,
we
discuss
application
cavity-enhanced
high-order
harmonic
generation,
with
repetition
rates
exceeding
10
MHz,
experiments
using
advanced
endstations
incorporating
time-of-flight
analyzers.
We
recent
results,
on
future
areas
for
further
technological
improvement,
wide
array
science
enabled
by
ultrafast
XUV
experiments,
now
a
qualitatively
new
regime.
Scientific Reports,
Год журнала:
2025,
Номер
15(1)
Опубликована: Янв. 29, 2025
Time-resolved
momentum
microscopy
is
an
emerging
technique
based
on
photoelectron
spectroscopy
for
characterizing
ultrafast
electron
dynamics
and
the
out-of-equilibrium
electronic
structure
of
materials
in
entire
Brillouin
zone
with
high
efficiency.
In
this
article,
we
introduce
a
setup
time-resolved
energy-filtered
microscope
coupled
to
custom-made
high-harmonic
generation
photon
source
driven
by
multi-100
kHz
commercial
Yb-ultrafast
laser
that
delivers
fs
pulses
extreme
ultraviolet
range.
The
includes
nonlinear
pulse
compression
stage
employing
spectral
broadening
Herriott-type
bulk-based
multi-pass
cell.
This
element
allows
flexible
tuning
driving
duration,
providing
versatile
featuring
two
operational
modes
designed
enhance
either
energy
or
time
resolution.
We
show
capabilities
system
tracing
conduction
band
valleys
bulk
crystal
2D
semiconductor
WS2.
Using
uncompressed
pulses,
demonstrate
resolution
better
than
(107
±
2)
meV,
while
compressed
lead
(48.8
17)
fs.
The Journal of Chemical Physics,
Год журнала:
2025,
Номер
162(6)
Опубликована: Фев. 10, 2025
In
recent
years,
computational
approaches
which
couple
density
functional
theory
(DFT)-based
description
of
the
electron–phonon
and
phonon–phonon
scattering
rates
with
Boltzmann
transport
equation
have
been
shown
to
obtain
electron
thermal
characteristics
many
3D
2D
semiconductors
in
excellent
agreement
experimental
measurements.
At
same
time,
progress
DFT-based
has
also
allowed
describe
non-equilibrium
relaxation
dynamics
hot
or
photo-excited
electrons
several
materials,
very
good
time-resolved
spectroscopy
experiments.
latter
case,
as
techniques
provide
possibility
monitor
transient
material
evolving
on
femtosecond
attosecond
time
scales,
evolution
photo-excited,
nonthermal
carrier
distributions
be
described.
Similarly,
reliable
theoretical
are
needed
properties
devices
involving
high
energy
carriers.
this
review,
we
aim
discuss
coupling
ab
initio
especially
that
scattering,
time-dependent
describing
out-of-equilibrium
distributions,
context
experiments
well
simulations.
We
point
out
limitations
common
all
numerical
approaches,
propagation
strongly
methods
used
overcome
them.
Review of Scientific Instruments,
Год журнала:
2025,
Номер
96(2)
Опубликована: Фев. 1, 2025
Oscillatory
signals
from
coherently
excited
phonons
are
regularly
observed
in
ultrafast
pump–probe
experiments
on
condensed
matter
samples.
Electron–phonon
coupling
implies
that
coherent
also
modulate
the
electronic
band
structure.
These
oscillations
can
be
probed
with
energy
and
momentum
resolution
using
time-
angle-resolved
photoemission
spectroscopy
(trARPES),
which
reveals
orbital
dependence
of
electron–phonon
for
a
specific
phonon
mode.
However,
comprehensive
analysis
remains
challenging
when
multiple
modes
couple
to
bands.
Complex
spectral
line
shapes
due
strong
correlations
quantum
materials
add
this
challenge.
In
work,
we
examine
how
frequency
domain
representation
trARPES
data
facilitates
quantitative
We
investigate
intensity
first
moment
distribution
curves.
Both
quantities
provide
complementary
information
able
distinguish
binding
energy,
linewidth,
intensity.
analyze
representative
dataset
transition
metal
dichalcogenide
WTe2
construct
composite
spectra,
intuitively
illustrate
much
each
is
affected
by
show
linearly
chirped
probe
pulse
generate
extrinsic
artifacts
distinct
intrinsic
signal.
Crystals,
Год журнала:
2024,
Номер
14(5), С. 404 - 404
Опубликована: Апрель 26, 2024
Over
the
last
two
decades,
time-
and
angle-resolved
photoemission
spectroscopy
(trARPES)
has
become
a
mature
established
experimental
technique
for
study
of
ultrafast
electronic
structural
dynamics
in
materials.
To
date,
most
trARPES
investigations
have
focused
on
investigation
processes
occurring
time
scales
≳30
fs,
particular,
relaxation
thermalization,
therefore
been
blind
to
initial
sub-10
fs
related
coherence
correlation
effects.
In
this
article,
we
illustrate
how
current
setups
reach
their
limits
when
it
comes
addressing
such
extraordinarily
short
present
an
configuration
that
provides
time,
energy,
momentum
resolutions
required
monitor
few-femtosecond
relevant
energy
scales.
We
discuss
potential
capabilities
experiment
response
materials
strong-field
interaction
regime
at
PHz
frequencies
finally
review
theoretical
concept
may
future
even
overcome
competing
resolution
limitations
experiments,
as
imposed
by
time–bandwidth
product
probing
laser
pulse.
Our
roadmap
indicates
path
break
new
ground
quantum
nonequilibrium
dynamics,
from
which
possibilities
control
optical
signals
can
be
explored.
We
describe
coupled
nonequilibrium
electron-phonon
systems
semiclassically—Ehrenfest
dynamics
for
the
phonons
and
quantum
mechanics
electrons—using
a
classical
Monte
Carlo
approach
that
determines
response
to
large
pump
field.
The
semiclassical
is
expected
be
accurate,
because
are
excited
average
energies
much
higher
than
phonon
frequency,
eliminating
need
description.
numerical
efficiency
of
this
method
allows
us
perform
self-consistent
time
evolution
out
very
long
times
(tens
picoseconds),
enabling
model
pump-probe
experiments
charge-density-wave
(CDW)
material.
Our
system
half-filled,
one-dimensional
(1D)
Holstein
chain
exhibits
CDW
ordering
due
Peierls
transition.
subjected
time-dependent
electromagnetic
field
excites
it
equilibrium,
then
second
probe
pulse
applied
after
delay.
By
evolving
times,
we
capture
complete
process
lattice
excitation
subsequent
relaxation
new
an
exchange
energy
between
electrons
lattice,
leading
at
finite
temperatures.
employ
indirect
(impulsive)
driving
mechanism
by
direct
electrons.
identify
two
regimes,
where
can
either
cause
small
perturbations
or
completely
invert
initial
order.
work
successfully
describes
ringing
amplitude
mode
in
has
been
seen
experiment
but
never
explained
microscopic
theory.
also
fluence-dependent
crossover
inverts
order
parameter
changes
dynamics.
Finally,
illustrate
how
examine
number
different
types
including
photoemission,
x-ray
diffraction,
two-dimensional
(2D)
spectroscopy.
Published
American
Physical
Society
2024
