Aaron Lindenberg
Associate Professor of Materials Science and Engineering and of Photon Science
Bio
Lindenberg's research is focused on visualizing the ultrafast dynamics and atomic-scale structure of materials on femtosecond and picosecond time-scales. X-ray techniques are combined with ultrafast optical techniques to provide a new way of taking snapshots of materials in motion. Current research is focused on the dynamics of phase transitions, ultrafast properties of nanoscale materials, and charge transport, with a focus on materials for information storage technologies, energy-related materials, and nanoscale optoelectronic devices.
Academic Appointments
-
Associate Professor, Materials Science and Engineering
-
Associate Professor, Photon Science Directorate
-
Affiliate, Precourt Institute for Energy
Honors & Awards
-
Young Faculty Award, DARPA (2010)
-
Terman Fellow, Stanford University (2007-2009)
-
Faculty Fellow Post-doctoral Fellowship, University of California, Berkeley (2001-2003)
-
Prize in Physics, Alfred Moritz Michaelis (1996)
-
I.I. Rabi Scholar, Columbia University (1992-1996)
Professional Education
-
BA, Columbia University (1996)
-
PhD, UC Berkeley (2001)
2015-16 Courses
- Materials Science Colloquium
MATSCI 230 (Win) - Quantum Mechanics of Nanoscale Materials
MATSCI 157 (Win) - X-Ray Science and Techniques
MATSCI 326, PHOTON 326 (Aut) -
Independent Studies (7)
- Graduate Independent Study
MATSCI 399 (Aut, Win, Spr, Sum) - Master's Research
MATSCI 200 (Aut, Win, Spr, Sum) - Participation in Materials Science Teaching
MATSCI 400 (Win, Spr) - Ph.D. Research
MATSCI 300 (Aut, Win, Spr, Sum) - Practical Training
MATSCI 299 (Aut, Win, Spr, Sum) - Undergraduate Independent Study
MATSCI 100 (Aut, Win, Spr, Sum) - Undergraduate Research
MATSCI 150 (Aut, Win, Spr, Sum)
- Graduate Independent Study
-
Prior Year Courses
2014-15 Courses
- Quantum Mechanics of Nanoscale Materials
MATSCI 157 (Win)
2013-14 Courses
- Materials Science Colloquium
MATSCI 230 (Win) - Quantum Mechanics of Nanoscale Materials
MATSCI 157 (Win) - X-Ray Science and Techniques
MATSCI 326, PHOTON 326 (Aut)
2012-13 Courses
- Quantum Mechanics of Nanoscale Materials
MATSCI 157 (Win)
- Quantum Mechanics of Nanoscale Materials
All Publications
-
How Supercooled Liquid Phase-Change Materials Crystallize: Snapshots after Femtosecond Optical Excitation
CHEMISTRY OF MATERIALS
2015; 27 (16): 5641-5646
View details for DOI 10.1021/acs.chemmater.5b02011
View details for Web of Science ID 000360323700024
-
THz-Pulse-Induced Selective Catalytic CO Oxidation on Ru.
Physical review letters
2015; 115 (3): 036103-?
Abstract
We demonstrate the use of intense, quasi-half-cycle THz pulses, with an associated electric field component comparable to intramolecular electric fields, to direct the reaction coordinate of a chemical reaction by stimulating the nuclear motions of the reactants. Using a strong electric field from a THz pulse generated via coherent transition radiation from an ultrashort electron bunch, we present evidence that CO oxidation on Ru(0001) is selectively induced, while not promoting the thermally induced CO desorption process. The reaction is initiated by the motion of the O atoms on the surface driven by the electric field component of the THz pulse, rather than thermal heating of the surface.
View details for PubMedID 26230806
-
THz-Pulse-Induced Selective Catalytic CO Oxidation on Ru
PHYSICAL REVIEW LETTERS
2015; 115 (3)
View details for DOI 10.1103/PhysRevLett.115.036103
View details for Web of Science ID 000358024500005
-
Mega-electron-volt ultrafast electron diffraction at SLAC National Accelerator Laboratory
REVIEW OF SCIENTIFIC INSTRUMENTS
2015; 86 (7)
Abstract
Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.
View details for DOI 10.1063/1.4926994
View details for Web of Science ID 000358934400053
View details for PubMedID 26233391
-
Visualization of nanocrystal breathing modes at extreme strains
NATURE COMMUNICATIONS
2015; 6
Abstract
Nanoscale dimensions in materials lead to unique electronic and structural properties with applications ranging from site-specific drug delivery to anodes for lithium-ion batteries. These functional properties often involve large-amplitude strains and structural modifications, and thus require an understanding of the dynamics of these processes. Here we use femtosecond X-ray scattering techniques to visualize, in real time and with atomic-scale resolution, light-induced anisotropic strains in nanocrystal spheres and rods. Strains at the percent level are observed in CdS and CdSe samples, associated with a rapid expansion followed by contraction along the nanosphere or nanorod radial direction driven by a transient carrier-induced stress. These morphological changes occur simultaneously with the first steps in the melting transition on hundreds of femtosecond timescales. This work represents the first direct real-time probe of the dynamics of these large-amplitude strains and shape changes in few-nanometre-scale particles.
View details for DOI 10.1038/ncomms7577
View details for Web of Science ID 000352720700012
View details for PubMedID 25762350
-
Color Switching with Enhanced Optical Contrast in Ultrathin Phase-Change Materials and Semiconductors Induced by Femtosecond Laser Pulses
ACS PHOTONICS
2015; 2 (2): 178-182
View details for DOI 10.1021/ph500402r
View details for Web of Science ID 000349814400002
-
Room-temperature stabilization of nanoscale superionic Ag2Se
NANOTECHNOLOGY
2014; 25 (41)
View details for DOI 10.1088/0957-4484/25/41/415705
View details for Web of Science ID 000342580300016
-
Room-temperature stabilization of nanoscale superionic Ag2Se.
Nanotechnology
2014; 25 (41): 415705-?
Abstract
Superionic materials are multi-component solids in which one sub-lattice exhibits high ionic conductivity within a fixed crystalline structure. This is typically associated with a structural phase transition occurring significantly above room temperature. Here, through combined temperature-resolved x-ray diffraction and differential scanning calorimetry, we map out the nanoscale size-dependence of the Ag₂Se tetragonal to superionic phase transition temperature and determine the threshold size for room-temperature stabilization of superionic Ag2Se. For the first time, clear experimental evidence for such stabilization of the highly ionic conducting phase at room temperature is obtained in ∼2 nm diameter spheres, which corresponds to a >100 °C suppression of the bulk phase transition temperature. This may enable technological applications of Ag₂Se in devices where high ionic conductivity at room temperature is required.
View details for DOI 10.1088/0957-4484/25/41/415705
View details for PubMedID 25249347
-
Ultrafast Electronic and Structural Response of Monolayer MoS2 under Intense Photoexcitation Conditions
ACS NANO
2014; 8 (10): 10734-10742
View details for DOI 10.1021/nn5044542
View details for Web of Science ID 000343952600110
-
Reversible Optical Switching of Infrared Antenna Resonances with Ultrathin Phase-Change Layers Using Femtosecond Laser Pulses
ACS PHOTONICS
2014; 1 (9): 833-839
View details for DOI 10.1021/ph500121d
View details for Web of Science ID 000342120300012
-
Picosecond carrier recombination dynamics in chalcogen-hyperdoped silicon
APPLIED PHYSICS LETTERS
2014; 105 (5)
View details for DOI 10.1063/1.4892357
View details for Web of Science ID 000341153000105
-
Ultrafast Polarization Response of an Optically Trapped Single Ferroelectric Nanowire
NANO LETTERS
2014; 14 (8): 4322-4327
Abstract
One-dimensional potassium niobate nanowires are of interest as building blocks in integrated piezoelectric devices, exhibiting large nonlinear optical and piezoelectric responses. Here we present femtosecond measurements of light-induced polarization dynamics within an optically trapped ferroelectric nanowire, using the second-order nonlinear susceptibility as a real-time structural probe. Large amplitude, reversible modulations of the nonlinear susceptibility are observed within single nanowires at megahertz repetition rates, developing on few-picosecond time-scales, associated with anomalous coupling of light into the nanowire.
View details for DOI 10.1021/nl5011228
View details for Web of Science ID 000340446200019
View details for PubMedID 25051318
-
Below gap optical absorption in GaAs driven by intense, single-cycle coherent transition radiation
OPTICS EXPRESS
2014; 22 (14): 17423-17429
Abstract
Single-cycle terahertz fields generated by coherent transition radiation from a relativistic electron beam are used to study the high field optical response of single crystal GaAs. Large amplitude changes in the sub-band-gap optical absorption are induced and probed dynamically by measuring the absorption of a broad-band optical beam generated by transition radiation from the same electron bunch, providing an absolutely synchronized pump and probe geometry. This modification of the optical properties is consistent with strong-field-induced electroabsorption. These processes are pertinent to a wide range of nonlinear terahertz-driven light-matter interactions anticipated at accelerator-based sources.
View details for DOI 10.1364/OE.22.017423
View details for Web of Science ID 000340674700072
View details for PubMedID 25090555
-
Ultrafast terahertz-induced response of GeSbTe phase-change materials
APPLIED PHYSICS LETTERS
2014; 104 (25)
View details for DOI 10.1063/1.4884816
View details for Web of Science ID 000338515900032
-
Measurement of transient atomic displacements in thin films with picosecond and femtometer resolution
STRUCTURAL DYNAMICS-US
2014; 1 (3)
View details for DOI 10.1063/1.4875347
View details for Web of Science ID 000354989200001
-
Real-Time Visualization of Nanocrystal Solid-Solid Transformation Pathways
NANO LETTERS
2014; 14 (4): 1995-1999
Abstract
Measurement and understanding of the microscopic pathways materials follow as they transform is crucial for the design and synthesis of new metastable phases of matter. Here we employ femtosecond single-shot X-ray diffraction techniques to measure the pathways underlying solid-solid phase transitions in cadmium sulfide nanorods, a model system for a general class of martensitic transformations. Using picosecond rise-time laser-generated shocks to trigger the transformation, we directly observe the transition state dynamics associated with the wurtzite-to-rocksalt structural phase transformation in cadmium sulfide with atomic-scale resolution. A stress-dependent transition path is observed. At high peak stresses, the majority of the sample is converted directly into the rocksalt phase with no evidence of an intermediate prior to rocksalt formation. At lower peak stresses, a transient five-coordinated intermediate structure is observed consistent with previous first principles modeling.
View details for DOI 10.1021/nl500043c
View details for Web of Science ID 000334572400048
View details for PubMedID 24588125
-
Fourier-transform inelastic X-ray scattering from time- and momentum-dependent phonon-phonon correlations
NATURE PHYSICS
2013; 9 (12): 790-794
View details for DOI 10.1038/NPHYS2788
View details for Web of Science ID 000327944600017
-
High-pressure Raman spectroscopy of phase change materials
APPLIED PHYSICS LETTERS
2013; 103 (19)
View details for DOI 10.1063/1.4829358
View details for Web of Science ID 000327817000029
-
Ultrafast sub-threshold photo-induced response in crystalline and amorphous GeSbTe thin films
APPLIED PHYSICS LETTERS
2013; 102 (20)
View details for DOI 10.1063/1.4807731
View details for Web of Science ID 000320619300035
-
Intense terahertz pulses from SLAC electron beams using coherent transition radiation.
Review of scientific instruments
2013; 84 (2): 022701-?
Abstract
SLAC has two electron accelerators, the Linac Coherent Light Source (LCLS) and the Facility for Advanced Accelerator Experimental Tests (FACET), providing high-charge, high-peak-current, femtosecond electron bunches. These characteristics are ideal for generating intense broadband terahertz (THz) pulses via coherent transition radiation. For LCLS and FACET respectively, the THz pulse duration is typically 20 and 80 fs RMS and can be tuned via the electron bunch duration; emission spectra span 3-30 THz and 0.5 THz-5 THz; and the energy in a quasi-half-cycle THz pulse is 0.2 and 0.6 mJ. The peak electric field at a THz focus has reached 4.4 GV/m (0.44 V/Å) at LCLS. This paper presents measurements of the terahertz pulses and preliminary observations of nonlinear materials response.
View details for DOI 10.1063/1.4790427
View details for PubMedID 23464183
-
Intense terahertz pulses from SLAC electron beams using coherent transition radiation
REVIEW OF SCIENTIFIC INSTRUMENTS
2013; 84 (2)
View details for DOI 10.1063/1.4790427
View details for Web of Science ID 000316954600003
-
The mechanism of ultrafast structural switching in superionic copper (I) sulphide nanocrystals
NATURE COMMUNICATIONS
2013; 4
Abstract
Superionic materials are multi-component solids with simultaneous characteristics of both a solid and a liquid. Above a critical temperature associated with a structural phase transition, they exhibit liquid-like ionic conductivities and dynamic disorder within a rigid crystalline structure. Broad applications as electrochemical storage materials and resistive switching devices follow from this abrupt change in ionic mobility, but the microscopic pathways and speed limits associated with this switching process are largely unknown. Here we use ultrafast X-ray spectroscopy and scattering techniques to obtain an atomic-level, real-time view of the transition state in copper sulphide nanocrystals. We observe the transformation to occur on a twenty picosecond timescale and show that this is determined by the ionic hopping time.
View details for DOI 10.1038/ncomms2385
View details for Web of Science ID 000316614600039
View details for PubMedID 23340409
-
Photon-Counting Detectors for Pump-Probe Science
2013 IEEE NUCLEAR SCIENCE SYMPOSIUM AND MEDICAL IMAGING CONFERENCE (NSS/MIC)
2013
View details for Web of Science ID 000347163503065
-
Fourier-transform inelastic X-ray scattering from time and momentum dependent phonon-phonon correlations
Nat. Phys.
2013
View details for DOI 10.1038/NPHYS2788
- High-pressure Raman spectroscopy of phase change materials Appl. Phys. Lett. 2013; 103: 191108
-
Ultrafast Photovoltaic Response in Ferroelectric Nanolayers
PHYSICAL REVIEW LETTERS
2012; 108 (8)
Abstract
We show that light drives large-amplitude structural changes in thin films of the prototypical ferroelectric PbTiO3 via direct coupling to its intrinsic photovoltaic response. Using time-resolved x-ray scattering to visualize atomic displacements on femtosecond time scales, photoinduced changes in the unit-cell tetragonality are observed. These are driven by the motion of photogenerated free charges within the ferroelectric and can be simply explained by a model including both shift and screening currents, associated with the displacement of electrons first antiparallel to and then parallel to the ferroelectric polarization direction.
View details for DOI 10.1103/PhysRevLett.108.087601
View details for Web of Science ID 000300669600033
View details for PubMedID 22463572
-
Optical Probes of Ultrafast Electron Dynamics in Photoexcited Ferroelectrics
2012 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)
2012
View details for Web of Science ID 000310362402099
-
Ultrafast x-ray spectroscopic and scattering studies of nanoscale superionic phase transitions
2012 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)
2012
View details for Web of Science ID 000310362402210
-
Ultrafast Optical and X-ray Probes of Nanoscale Solid-Liquid Phase Transformations
2012 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)
2012
View details for Web of Science ID 000310362403161
-
Observations of laser induced magnetization dynamics in Co/Pd multilayers with coherent x-ray scattering
APPLIED PHYSICS LETTERS
2011; 99 (25)
View details for DOI 10.1063/1.3670305
View details for Web of Science ID 000299031600042
-
Single-cycle terahertz pulses with > 0.2 V/angstrom field amplitudes via coherent transition radiation
APPLIED PHYSICS LETTERS
2011; 99 (14)
View details for DOI 10.1063/1.3646399
View details for Web of Science ID 000295625100017
-
Observation of Transient Structural-Transformation Dynamics in a Cu2S Nanorod
SCIENCE
2011; 333 (6039): 206-209
Abstract
The study of first-order structural transformations has been of great interest to scientists in many disciplines. Expectations from phase-transition theory are that the system fluctuates between two equilibrium structures near the transition point and that the region of transition broadens in small crystals. We report the direct observation of structural fluctuations within a single nanocrystal using transmission electron microscopy. We observed trajectories of structural transformations in individual nanocrystals with atomic resolution, which reveal details of the fluctuation dynamics, including nucleation, phase propagation, and pinning of structural domains by defects. Such observations provide crucial insight for the understanding of microscopic pathways of phase transitions.
View details for DOI 10.1126/science.1204713
View details for Web of Science ID 000292502700045
View details for PubMedID 21737738
-
Generation of > 100 mu J, Broadband THz Transients with > 10 MV/cm Fields via Coherent Transition Radiation at the Linac Coherent Light Source
2011 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)
2011
View details for Web of Science ID 000295612401212
-
High-speed all-optical terahertz polarization switching by a transient plasma phase modulator
APPLIED PHYSICS LETTERS
2010; 96 (16)
View details for DOI 10.1063/1.3407514
View details for Web of Science ID 000277020600003
- Ultrafast Conversions of Hydrogen-Bonded Structures in Liquid Water Observed via Femtosecond Soft X-Ray Spectroscopy 2010
-
High-intensity THz interactions with materials: New aspects and applications
INTERNATIONAL SYMPOSIUM ON HIGH POWER LASER ABLATION 2010
2010; 1278: 17-25
View details for Web of Science ID 000287183900002
- Light-Induced Modulation of Ferroelectric Polarization Probed Using Time-Resolved X-Ray Scattering 2010
-
Ultrafast conversions between hydrogen bonded structures in liquid water observed by femtosecond x-ray spectroscopy
JOURNAL OF CHEMICAL PHYSICS
2009; 131 (23)
Abstract
We present the first femtosecond soft x-ray spectroscopy in liquids, enabling the observation of changes in hydrogen bond structures in water via core-hole excitation. The oxygen K-edge of vibrationally excited water is probed with femtosecond soft x-ray pulses, exploiting the relation between different water structures and distinct x-ray spectral features. After excitation of the intramolecular OH stretching vibration, characteristic x-ray absorption changes monitor the conversion of strongly hydrogen-bonded water structures to more disordered structures with weaker hydrogen-bonding described by a single subpicosecond time constant. The latter describes the thermalization time of vibrational excitations and defines the characteristic maximum rate with which nonequilibrium populations of more strongly hydrogen-bonded water structures convert to less-bonded ones. On short time scales, the relaxation of vibrational excitations leads to a transient high-pressure state and a transient absorption spectrum different from that of statically heated water.
View details for DOI 10.1063/1.3273204
View details for Web of Science ID 000273036300029
View details for PubMedID 20025333
-
Coherent Terahertz Polarization Control through Manipulation of Electron Trajectories
PHYSICAL REVIEW LETTERS
2009; 103 (2)
Abstract
The dynamics of ionized electrons in a plasma can be controlled by synthetic optical fields composed of the fundamental and the second harmonic of femtosecond optical pulses with an arbitrary phase and polarization. We show here that the plasma-emitted half-cycle THz radiation directly reflects the two-dimensional trajectories of the electrons through polarization sensitive THz emission spectroscopy. As a result, we find that the THz polarization smoothly rotates through 2pi radians as the relative phase between the two pulses is adjusted, providing a new means of coherently controlling the polarization of light at THz frequencies.
View details for DOI 10.1103/PhysRevLett.103.023902
View details for Web of Science ID 000267887800020
View details for PubMedID 19659205
-
Probing the hydrogen-bond network of water via time-resolved soft X-ray spectroscopy
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
2009; 11 (20): 3951-3957
Abstract
We report time-resolved studies of hydrogen bonding in liquid H(2)O, in response to direct excitation of the O-H stretch mode at 3 mum, probed via soft X-ray absorption spectroscopy at the oxygen K-edge. This approach employs a newly developed nanofluidic cell for transient soft X-ray spectroscopy in the liquid phase. Distinct changes in the near-edge spectral region (XANES) are observed, and are indicative of a transient temperature rise of 10 K following transient laser excitation and rapid thermalization of vibrational energy. The rapid heating occurs at constant volume and the associated increase in internal pressure, estimated to be 8 MPa, is manifested by distinct spectral changes that differ from those induced by temperature alone. We conclude that the near-edge spectral shape of the oxygen K-edge is a sensitive probe of internal pressure, opening new possibilities for testing the validity of water models and providing new insight into the nature of hydrogen bonding in water.
View details for DOI 10.1039/b822210j
View details for Web of Science ID 000266065400018
View details for PubMedID 19440624
-
Ultrafast Electron Cascades Driven by Intense Femtosecond THz Pulses
ULTRAFAST PHENOMENA XVI
2009; 92: 654-656
View details for Web of Science ID 000282108000212
-
Coherent Control of the Polarization of Ultrafast Terahertz Pulses
2009 CONFERENCE ON LASERS AND ELECTRO-OPTICS AND QUANTUM ELECTRONICS AND LASER SCIENCE CONFERENCE (CLEO/QELS 2009), VOLS 1-5
2009: 640-641
View details for Web of Science ID 000274751300322
-
Ultrafast electron cascades in semiconductors driven by intense femtosecond terahertz pulses
PHYSICAL REVIEW B
2008; 78 (12)
View details for DOI 10.1103/PhysRevB.78.125203
View details for Web of Science ID 000259691500036
-
X-ray diffuse scattering measurements of nucleation dynamics at femtosecond resolution
PHYSICAL REVIEW LETTERS
2008; 100 (13)
Abstract
Femtosecond time-resolved small and wide angle x-ray diffuse scattering techniques are applied to investigate the ultrafast nucleation processes that occur during the ablation process in semiconducting materials. Following intense optical excitation, a transient liquid state of high compressibility characterized by large-amplitude density fluctuations is observed and the buildup of these fluctuations is measured in real time. Small-angle scattering measurements reveal snapshots of the spontaneous nucleation of nanoscale voids within a metastable liquid and support theoretical predictions of the ablation process.
View details for DOI 10.1103/PhysRevLett.100.135502
View details for Web of Science ID 000254670300046
View details for PubMedID 18517965
-
Formation of secondary electron cascades in single-crystalline plasma-deposited diamond upon exposure to femtosecond x-ray pulses
JOURNAL OF APPLIED PHYSICS
2008; 103 (6)
View details for DOI 10.1063/1.2890158
View details for Web of Science ID 000254536900143
-
Femtosecond x-ray diffuse scattering measurements of semiconductor ablation dynamics
HIGH-POWER LASER ABLATION VII, PTS 1-2
2008; 7005
View details for DOI 10.1117/12.784094
View details for Web of Science ID 000258905800002
- Measurement of high-field THz-induced photocurrents in semiconductors Journal of Undergraduate Research 2008; 8
-
Nonlinear THz-pump/THz-probe measurements of semiconductor carrier dynamics
2008 CONFERENCE ON LASERS AND ELECTRO-OPTICS & QUANTUM ELECTRONICS AND LASER SCIENCE CONFERENCE, VOLS 1-9
2008: 322-323
View details for Web of Science ID 000260498400162
-
Large acoustic transients induced by nonthermal melting of InSb
PHYSICAL REVIEW LETTERS
2007; 98 (22)
Abstract
We have observed large-amplitude strain waves following a rapid change in density of InSb due to nonthermal melting. The strain has been measured in real time via time-resolved x-ray diffraction, with a temporal resolution better than 2 ps. The change from the solid to liquid density of the surface layer launches a high-amplitude strain wave into the crystalline material below. This induces an effective plane rotation in the asymmetrically cut crystal leading to deflection of the diffracted beam. The uniform strain in the layer below the molten layer is 2.0(+/-0.2)%. A strain of this magnitude develops within 5 ps of the incident pulse showing that the liquid has reached the equilibrium density within this time frame. Both the strain amplitude and the depth of the strained material in the solid can be explained by assuming a reduction in the speed of sound in the nonequilibrium liquid compared to measured equilibrium values.
View details for DOI 10.1103/PhysRevLett.98.225502
View details for Web of Science ID 000246910100037
View details for PubMedID 17677856
-
Carrier-density-dependent lattice stability in InSb
PHYSICAL REVIEW LETTERS
2007; 98 (12)
Abstract
The ultrafast decay of the x-ray diffraction intensity following laser excitation of an InSb crystal has been utilized to observe carrier dependent changes in the potential energy surface. For the first time, an abrupt carrier dependent onset for potential energy surface softening and the appearance of accelerated atomic disordering for a very high average carrier density have been observed. Inertial dynamics dominate the early stages of crystal disordering for a wide range of carrier densities between the onset of crystal softening and the appearance of accelerated atomic disordering.
View details for DOI 10.1103/PhysRevLett.98.125501
View details for Web of Science ID 000245135400034
View details for PubMedID 17501133
-
Ultrafast bond softening in bismuth: Mapping a solid's interatomic potential with X-rays
SCIENCE
2007; 315 (5812): 633-636
Abstract
Intense femtosecond laser excitation can produce transient states of matter that would otherwise be inaccessible to laboratory investigation. At high excitation densities, the interatomic forces that bind solids and determine many of their properties can be substantially altered. Here, we present the detailed mapping of the carrier density-dependent interatomic potential of bismuth approaching a solid-solid phase transition. Our experiments combine stroboscopic techniques that use a high-brightness linear electron accelerator-based x-ray source with pulse-by-pulse timing reconstruction for femtosecond resolution, allowing quantitative characterization of the interatomic potential energy surface of the highly excited solid.
View details for DOI 10.1126/science.1135009
View details for Web of Science ID 000243909400039
View details for PubMedID 17272718
-
Ultrafast X-ray scattering in solids
LIGHT SCATTERING IN SOLIDS IX
2007; 108: 371-422
View details for Web of Science ID 000243862500006
-
Carrier dependent stability of a semiconductor lattice measured with femtosecond X-ray diffraction
ULTRAFAST PHENOMENA XV
2007; 88: 710-712
View details for Web of Science ID 000250104700227
- Ultrafast optical and x-ray measurements of femtosecond lattice dynamics in photoexcited Bismuth edited by Corkum, P., Weiner, A., M., Miller, R., J. 2006
-
Observation of structural anisotropy and the onset of liquidlike motion during the nonthermal melting of InSb
PHYSICAL REVIEW LETTERS
2005; 95 (12)
Abstract
The melting dynamics of laser excited InSb have been studied with femtosecond x-ray diffraction. These measurements observe the delayed onset of diffusive atomic motion, signaling the appearance of liquidlike dynamics. They also demonstrate that the root-mean-squared displacement in the [111] direction increases faster than in the [110] direction after the first 500 fs. This structural anisotropy indicates that the initially generated fluid differs significantly from the equilibrium liquid.
View details for DOI 10.1103/PhysRevLett.95.125701
View details for Web of Science ID 000231908200033
View details for PubMedID 16197085
-
Time-resolved measurements of the structure of water at constant density
JOURNAL OF CHEMICAL PHYSICS
2005; 122 (20)
Abstract
Dynamical changes in the structure factor of liquid water, S(Q,t), are measured using time-resolved x-ray diffraction techniques with 100 ps resolution. On short time scales following femtosecond optical excitation, we observe temperature-induced changes associated with rearrangements of the hydrogen-bonded structure at constant volume, before the system has had time to expand. We invert this data to extract transient changes in the pair correlation function associated with isochoric heating effects, and interpret these in terms of a decrease in the local tetrahedral ordering.
View details for DOI 10.1063/1.1906212
View details for Web of Science ID 000229544500046
View details for PubMedID 15945752
-
Atomic-scale visualization of inertial dynamics
SCIENCE
2005; 308 (5720): 392-395
Abstract
The motion of atoms on interatomic potential energy surfaces is fundamental to the dynamics of liquids and solids. An accelerator-based source of femtosecond x-ray pulses allowed us to follow directly atomic displacements on an optically modified energy landscape, leading eventually to the transition from crystalline solid to disordered liquid. We show that, to first order in time, the dynamics are inertial, and we place constraints on the shape and curvature of the transition-state potential energy surface. Our measurements point toward analogies between this nonequilibrium phase transition and the short-time dynamics intrinsic to equilibrium liquids.
View details for DOI 10.1126/science.1107996
View details for Web of Science ID 000228492000046
View details for PubMedID 15831753
-
Clocking femtosecond x rays
PHYSICAL REVIEW LETTERS
2005; 94 (11)
Abstract
Linear-accelerator-based sources will revolutionize ultrafast x-ray science due to their unprecedented brightness and short pulse duration. However, time-resolved studies at the resolution of the x-ray pulse duration are hampered by the inability to precisely synchronize an external laser to the accelerator. At the Sub-Picosecond Pulse Source at the Stanford Linear-Accelerator Center we solved this problem by measuring the arrival time of each high energy electron bunch with electro-optic sampling. This measurement indirectly determined the arrival time of each x-ray pulse relative to an external pump laser pulse with a time resolution of better than 60 fs rms.
View details for DOI 10.1103/PhysRevLett.94.114801
View details for Web of Science ID 000227923200034
View details for PubMedID 15903864
-
Opportunities and challenges using short-pulse X-ray sources.
SECOND INTERNATIONAL CONFERENCE ON PHOTO-INDUCED PHASE TRANSITIONS: COOPERATIVE, NONLINEAR AND FUNCTIONAL PROPERTIES
2005; 21: 87-94
View details for DOI 10.1088/1742-6596/21/1/014
View details for Web of Science ID 000233012100014
- Bonding in liquid Carbon studied by time-resolved x-ray absorption spectroscopy Phys. Rev. Lett. 2005; 94: 57407
-
Time-resolved X-ray diffraction study of the ferroelectric phase-transition in DKDP
CHEMICAL PHYSICS
2004; 299 (2-3): 157-161
View details for DOI 10.1016/j.chemphys.2003.11.019
View details for Web of Science ID 000220525200002
- A setup for ultrafast time-resolved x-ray absorption spectroscopy Rev. Sci. Instr. 2004; 75: 24
-
A setup for ultrafast time-resolved x-ray absorption spectroscopy
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (1): 24-30
View details for DOI 10.1063/1.1633003
View details for Web of Science ID 000187536500003
- Time-resolved x-ray diffraction study of the ferroelectric phase transition in DKDP Chem. Phys. 2004; 299: 157
-
Transient strain driven by a dense electron-hole plasma
PHYSICAL REVIEW LETTERS
2003; 91 (16)
Abstract
We measure transient strain in ultrafast laser-excited Ge by time-resolved x-ray anomalous transmission. The development of the coherent strain pulse is dominated by rapid ambipolar diffusion. This pulse extends considerably longer than the laser penetration depth because the plasma initially propagates faster than the acoustic modes. X-ray diffraction simulations are in agreement with the observed dynamics.
View details for DOI 10.1103/PhysRevLett.91.165502
View details for Web of Science ID 000186068300026
View details for PubMedID 14611411
- Properties of liquid Silicon observed by time-resolved x-ray absorption spectroscopy Phys. Rev. Lett. 2003; 91: 157403
-
Properties of liquid silicon and carbon studied by ultrafast time-resolved x-ray absorption spectroscopy
ULTRAFAST PHENOMENA XIII
2003; 71: 39-41
View details for Web of Science ID 000182432900011
- Transient strain driven by a dense, electron-hole plasma Phys. Rev. Lett. 2003; 91: 165502
-
Picosecond X-ray diffraction studies of laser-excited acoustic phonons in InSb
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
2002; 75 (4): 467-478
View details for DOI 10.1007/s003390201421
View details for Web of Science ID 000176768300002
- Coherent control of phonons probed by picosecond time-resolved x-ray diffraction Opt. Lett. 2002; 27: 869
-
Ultrafast X-ray diffraction of laser-irradiated crystals
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
2001; 467: 986-989
View details for Web of Science ID 000171012800037
- Ultrafast x-ray diffraction of laser-irradiated crystals Nucl. Inst. Meth. A 2001: 467-468,986-989
-
Time-resolved x-ray measurements of polaron dynamics of charge-ordered Nd1/2Sr1/2MnO3
ULTRAFAST PHENOMENA XII
2001; 66: 287-289
View details for Web of Science ID 000167460300083
- Femtosecond x-ray diffraction: experiments and limits 2001
-
Time-resolved X-ray diffraction from coherent phonons during a laser-induced phase transition
PHYSICAL REVIEW LETTERS
2000; 84 (1): 111-114
View details for Web of Science ID 000084587900028
- Time-resolved x-ray diffraction from coherent phonons during a laser-induced phase transition Phys. Rev. Lett. 2000; 84: 111
-
Time-resolved x-ray photoabsorption and diffraction on timescales from ns to fs
SYNCHROTRON RADIATION INSTRUMENTATION
2000; 521: 156-160
View details for Web of Science ID 000088762600029
-
Time-resolved x-ray photoabsorption and diffraction on timescales from ns to fs
X-RAY AND INNER-SHELL PROCESSES
2000; 506: 664-668
View details for Web of Science ID 000086079900052
- Ultrafast Lattice Dynamics Nonlinear Optics, Quantum Optics, and Ultrafast Phenomena with X-rays edited by Adams, B., W. Kluwer. 2000
-
Ultrafast structural changes measured by time-resolved X-ray diffraction
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
1998; 66 (6): 587-591
View details for Web of Science ID 000073953200001
- Ultrafast structural changes measured by time-resolved x-ray diffraction Appl. Phys. A 1998; 66: 587
-
Ultra-fast time-resolved x-ray diffraction detected by an averaging mode streak camera
APPLICATIONS OF HIGH-FIELD AND SHORT WAVELENGTH SOURCES
1998: 267-270
View details for Web of Science ID 000076265900042
-
Melting of a semiconductor crystal (InSb) with a short laser pulse (100 fs)
HIGH HEAT FLUX AND SYNCHROTRON RADIATION BEAMLINES
1997; 3151: 102-106
View details for Web of Science ID 000071550400009