lcls-ii-he science opportunities overview€¦ · • sensitivity (e.g. to electronic vs. lattice...

LCLS-II-HE “First Experiements” Meeting

Chemistry, Materials Physics

July 20-21, 2017 Robert Schoenlein LCLS Deputy for Science

LCLS-II-HE

Science Opportunities Overview

LCLS-II Project – Under Construction 1st Light - 2020

LCLS

LCLS-II 4 GeV

CW-SCRF SCRF Cryo-module

Average Coherent Power

LCLS-II

• CW-SCRF linac (4 GeV)

• Two new tunable undulators

• Repetition rate up to 1 MHz

• Photon energy up to 25 keV (120 Hz)

• Stability, coherence (seeding)

1019

1020

1021

1022

1023

1024

1025

1026

102 103 104

Existing Rings

LCLS

Ave

rage

Bri

ghtn

ess

(ph

/s/m

m2/m

rad

2/0

.1%

BW

)

Photon Energy (eV)

x 1

0,0

00

LCLS-II HXU

SXU

LCLS-II

LCLS

~10 msec ~mJ ~fs

~msec LCLS-II

EuXFEL (FLASH)

Proposed LCLS-II-HE

LCLS

LCLS-II 4 GeV

CW-SCRF

LCLS-II-HE

SCRF Cryo-module

LCLS-II-HE

• CW-SCRF linac (8 GeV)

• Photon energy up to 20 keV

• Two tunable undulators

• Repetition rate up to 1 MHz

• Stability, coherence (seeding)

LCLS

~10 msec ~mJ ~fs

~msec LCLS-II-HE

EuXFEL (FLASH)

Electronic dynamics Atomic-scale structure

Photon Energy (keV)

Ave

rag

e B

rig

htn

es

s

(ph

/s/m

m2/m

rad

2/0

.1%

BW

)

LCLS-II LCLS-II-HE

Eu-XFEL

LCLS

DLSR

limit

DLSR(s)

0.2-1.1 km, 2-6 GeV

6.3 km, 9 GeV

2 4 6 8 10 12 14 16 18 20

~1,000x

1019

1020

1021

1022

1023

1024

1025

1026

Dynamics excited state

non-equilibrium

transient structures

Heterogeneity structural complexity

ground & excited states

Fluctuations ground state structure

spontaneous evolution

LCLS-II-HE provides:

Ultrafast coherent X-rays

~1 Ångstrom (~12 keV)

High repetition rate

LCLS-II-HE provides new insight to structural dynamics

at the atomic scale

1 Å

5 6 7 8 9 10 11 12 13 14 15 0

0.02

0.04

0.06

0.08

0.1

0.12

Photon Energy (keV)

Tra

ns

mis

sio

n

V Cr Mn Fe Co Ni Cu Zn Ir-L3 Se

14.4 keV

Fe57 (Mossbauer)

~20 keV

High-resolution IXS

>25 keV

X-ray scattering, PDF

Structural dynamics at the atomic scale

- Atomic and electronic structure

- Large momentum (q) transfer

Operating environments

- X-ray penetration of water ~3 mm @ 12 keV

Earth-abundant

3d transition metals

Correlated materials

strong S-O (5d TM) PX structure

via Se phasing

Dynamics near the FT Limit

• >300x increase in average spectral flux (ph/s/meV) beyond DLSRs

• Spectroscopy & inelastic scattering at high resolution

• IXS meV resolution up to 20 keV

sub-meV (dispersive spectrometer, ~10 keV)

• RIXS ~5 meV (quartz- and sapphire-based analyzers)

• Low-energy modes in quasi-elastic energy region

• Momentum transfer spanning entire Brillouin zone

• Sensitivity (e.g. to electronic vs. lattice modes)

• Excited-state dynamics – near-equilibrium perturbations (5 meV 300 fs)

• Excited-state potential mapping with element-specificity

(e.g. metal-ligand stretch modes)

Dt1

Dt2

Dt3

hn

X-ray

ener

gy

Q

core-excited states

New Experimental Capabilities of LCLS-II-HE (1/3)

Hard X-ray Flux on Sample

Resolution ~100 meV 10 meV ~1 meV

LCLS-II-HE seeded (SASE) ~1014 (1013 ) ph/s ~1013 (1012) ph/s

ESRF ~1013 ph/s

(UPBL6)

~1011 ph/s (ID28) ~1010 ph/s (ID28)

SPring-8 ~1011 ph/s ~1010 ph/s

APS ~1012 ph/s

(MERIX)

~1011 ph/s ~1010 ph/s

~109 ph/s (UHRIXS)

NSLS-II ~1010 ph/s


Fluctuations & Heterogeneity

Atomic resolution, Ultrafast time scales, Operating conditions

Photon Correlation Spectroscopy (XPCS)

• “Sequential” real-time mode (fast 2D detectors)

• “Two-pulse” mode (<100 fs) with pulse pairs directly from XFEL

• “Programmable” time structure encoded in X-ray pulse sequence

• High rep rate, lower peak power, sample replacement

Time-domain (and FT) Inelastic X-ray Scattering

• Time-resolved (diffuse) X-ray scattering

following impulsive excitation of collective modes

• Perturbative regime – ground-state fluctuations

(fluctuation-dissipation theorem)

• Non-equilibrium regime, excited-state dynamics

• High resolution via Fourier-transform of coherent response

(1 THz 4 meV)

• High-brightness hard X-rays – atomic structure (PDF)

Dt1

Dt2

Dt3

Trigo et al., Nature Physics (2013)


How can we exploit the high rep rate and

the potential for 108-1010 snapshots/day to:

• Characterize heterogeneous ensembles,

• Capture rare transient events,

• Map spontaneous dynamics operando

Advanced Experimental Approaches • Coherent diffractive imaging (and/or serial crystallography)

with spectroscopy

• Solution scattering, rapid mixing…

• Fluctuation X-ray scattering

Advanced Computational Approaches and Data

Science • Mapping reaction landscapes via diffusion maps, manifold

embedding and related Bayesian approaches

• Capturing rare events via automatic pattern recognition and

related machine-learning approaches

~kT

Potential energy landscape

CXI of heterogeneous

nanoparticles in situ Möller et al., Nature Comm. (2014)

LCLS-II-HE Science Opportunities

Biological Function & Structural Dynamics Dynamics in physiological environments

Quantum Materials: Emergent phenomena & collective excitations

Materials Physics: Heterogeneity, nonequilibrium dynamics

& spontaneous fluctuations

Catalysis: Homogeneous and heterogeneous catalysis, interfacial

& geo/environmental chemistry

Chemical dynamics: Reaction dynamics, charge transfer,

molecular photocatalysts, natural & artificial photosynthesis

Revealing the full sequence of electronic/atomic structural

dynamics & capturing rare events in multi-electron catalysts

Scientific Opportunity • Reveal coupling of valence charge structure

and subtle changes in molecular structure • Map entire cycle of multi-electron photo-catalysts • Capture rare transient events (transition states) operando

Significance Impact • Link to theory & simulation • Validate design rules for efficient & robust

catalysts from abundant elements (3d TM)

LCLS-II-HE Approach • Time-resolved spectroscopy maps excited state

valence structure (XES) and potential surfaces (RIXS)

• Time-resolved scattering (and PDF), EXAFS map local geometry at the sub-angstrom scale

• 108-1010 snapshots/day captures rare transient events

Requires tunable ultrafast hard X-rays at high rep rate to map dynamics and to capture rare events of functional complexes

Inorganic water

oxidation catalyst H. Frei et al.

Nature Chem. (2014)

Molecular

photocatalytic

assembly K. Kjaer, Lund U.

Structural Dynamics, Interfaces,

& Electrochemical Energy Storage

S. Lapidus et al., PCCP (2014)

XPCS/CXI

H. Ogasawara

Scientific Opportunity • Unravel chemical, structural, & electronic

dynamics of the electrical double layer (interface) • Atomic resolution, operando

Significance and Impact • Critical input for electronic structure theory

& directed design of advanced batteries, electro-catalysts, solar fuel cells etc.

• Contaminant & elemental cycling in enviro-geochemistry

LCLS-II-HE Approach • Dynamic X-ray scattering methods span

many decades in time and space, to fs and Å • XPCS characterizes statistically dynamic systems

without long-range order, measuring S(q,t) • Time-resolved X-ray scattering (20 keV, large-q)

with Pair Distribution Function (PDF) analysis

Requires hard X-rays at high repetition rate & programmable pulse structure to capture dynamics of local changes in structure

Coupled electronic & nuclear dynamics are fundamental to

heterogeneous catalysis and interfacial chemistry

Scientific Opportunity

• Correlate catalytic reactivity & structure nanoparticle-by-nanoparticle

• Characterize evolving heterogeneous catalyst in real-time and operando with chemical specificity & atomic resolution

Significance and Impact

• Input for theory for directed design & synthesis of efficient, selective and robust systems based on earth-abundant elements

LCLS-II-HE Approach

• Coherent scattering and spectroscopy measured simultaneously provides electronic & atomic structure (shape) of each nanoparticle

• ~108-1010 independent measurements/day characterizes heterogeneous ensembles

Requires tunable ultrafast hard X-rays at high repetition rate to sample large ensembles

hn

hn e-

CXI

CXI of heterogeneous

nanoparticles in situ Möller et al., Nature Comm. (2014)

PtnSnm/γ-Al2O3 Ab Initio MD & XAS

J. Rehr et al. J. Phys. Chem. (2013)

Imaging of ion diffusion and fluctuating material structures


• Characterize local atomic distortions and long-range strain fields

• Resulting from ion diffusion in real materials under operating conditions

Significance and Impact • Inform directed design and synthesis of

energy conversion and storage materials

LCLS-II-HE Approach

• Dynamic X-ray scattering methods span many decades in time and space, down to fs and Å

• XPCS characterizes statistically dynamic systems without long-range order, measuring S(q,t)

Requires hard X-rays at high repetition rate & programmable pulse structure to capture dynamics of local changes in structure

Understanding ion diffusion at atomic level is central to performance improvements in electro-

chemical energy storage materials

ion

ion 3d metal-oxide

electrode

t1

t2

t3

100 fs ~1 Å/vsound M. Toney

5 µm Co

discharge

LiCoO2

The uniquely high spectral brightness opens a long-sought

window into emergent phenomena in complex materials


• Characterize collective modes in materials o Correlated materials - multiple strong interactions

charge, spin, orbital, lattice • Resonant: RIXS, non-resonant: IXS

o New insight from >300x ph/s/meV


• Fundamental material description: S(q,w)~c(q, w) o Limited resolution and precision to date

• Direct link to theory predictions for collective modes

LCLS-II-HE Approach

• Collective modes at ~1 meV scale and beyond o Continuum charge modes, e-ph coupling

• Span entire Brillouin zone: k-dependent coupling • Complex materials, high-Z elements, weak signals

Average spectral brightness of LCLS-II-HE will be ~1000x beyond existing X-ray sources

ela

stic p

ea

k

charge spin

orbital

lattice



DE=130 meV

DE=30 meV

Kim et al. PRL (2012) Kim et al. Nature Com. (2014)

Sr2IrO4








LCLS-II-HE Approach


• Span entire Brillouin zone: k-dependent coupling • Complex materials, high-Z elements, weak signals




20 THz modulation of Oxygen out-of-plane mode in YBCO

cuprate

superconductor

A. Cavalleri

THz-Driven Superconductivity Enhanced Tc ?

Order Parameter of Pseudo-gap Phase?

Magnetoelectric quadrupole via magnon- phonon coupling

U. Staub








LCLS-II-HE Approach


• Span entire Brillouin zone: k-dependent coupling • Complex materials, high-Z elements, weak signals • Dynamic response to tailored excitations


Imaging Biological Function - Biology in Action

Phytochrome – light sensing kinase

controls cellular function in bacteria & plants

Scientific Opportunity • Reveal structural dynamics of bio-molecules &

molecular machines on fundamental scales • Near physiological conditions – room temperature

Significance and Impact • Dynamics (e.g. low-energy collective motions) are key

missing link between biological structure & function • Beyond “model” complexes with large photolysis

to biologically relevant processes

LCLS-II-HE Approach • Serial nano-crystallography

complete time sequences at atomic scale • Larger-scale conformational changes:

Solution scattering (SAXS, fluctuation SAXS)

Trans to cis isomerization in PYP M. Schmidt et al., Science (2016)

CO-myoglobin ligand dissociation dynamics I. Schlichting et al., Science (2015)

Photo-triggered Dynamics

Understanding heterogeneous ensembles & dynamics under physiological conditions requires hard X-rays at high repetition rate

Imaging Biological Function - Biology in Action

Scientific Opportunity • Reveal structural dynamics of bio-molecules &

molecular machines on fundamental scales • Near physiological conditions – room temperature, solution

Significance and Impact • Dynamics (e.g. low-energy collective motions) are the key

missing link between biological structure & function • Beyond “model” complexes with large photolysis

to biologically relevant processes

LCLS-II-HE Approach • Solution scattering (SAXS, fluctuation SAXS)

complete time sequences of structural dynamics • Rapid mixing (~10 msec, <1 mm crystals, room temp.) • Activated substrates (small molecules, <10 msec) • Optogenetic & biological photo-actuators - trigger • 108-1010 snapshots/spectra per day rare transient events

AChE enzyme – synaptic transmission

active site

reaction turnover ~50,000/sec (20 msec)

~kT

Conformational (PE) landscape

Understanding heterogeneous ensembles & dynamics under physiological conditions requires hard X-rays at high repetition rate

lcls-ii-he science opportunities overview€¦ · • sensitivity (e.g. to electronic vs. lattice...

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