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Stanford Institute for Materials and Energy Sciences (SIMES) Field Stanford Institute for Materials and Energy Sciences (SIMES) Field Budget Request for FY2015 FWP Page Time‐Resolved Soft X-ray Materials Science at the LCLS & ALS 2 Diamondoid Science and Applications 10 Electronic and Magnetic Structure of Quantum Materials 14 Correlated Materials – Synthesis and Physical Properties 28 Spin Physics 36 Clathrin Biotemplating 39 Magnetization & Dynamic 43 Atomic Engineering Oxide Heterostructures: Materials by Design 46 High Energy Density Science at the SLAC National Accelerator Laboratory 52 Nanostructured Design of Sulfur Cathodes for High Energy Lithium-Sulfur Batteries 62 Pre-Lithiation of Silicon Anode for High Energy Li Ion Batteries 63 MEC User Workshop on High-Power Lasers 64 Field Work Proposal – SLAC National Accelerator Laboratory Date Submitted: 6/23/2014 SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS FWP#: 10017 Time‐Resolved Soft X-ray Materials Science at the LCLS & ALS Principal Investigator(s): T. P. Devereaux, Z.-X. Shen, Z. Hussain, A. Lindenberg, D. Reis, and W. Mao Staff Scientists: Wei-Sheng Lee, Yi-De Chuang, Mariano Trigo, Hongchen Jiang Postdoctoral Scholars and Graduate Students: Thomas Henighan, Te Hu, Shigeto Hirai, Mason Jiang, Sanghee Nah, Michael Sentef, Renee Sher, Michael Shu, Peter Zalden, Qiaoshi Zeng Overview: This program connects concepts of ultrafast time-domain science with those for momentum- and energy-domain x-ray spectroscopy. The FWP consists of the single-investigator small group research (SISGR) program (Devereaux, Lee, Shen, Moritz, Hussain, Chuang) on time-resolved soft x-ray materials science at the Linac Coherent Light Source (LCLS) and the Advanced Light Source (ALS), merged with the recent addition of high pressure studies (Mao) and ultrafast activities (Lindenberg, Reis) on non-equilibrium phonon dynamics and phase transitions, nanoscale dynamics and ferroelectric oxide ultrafast processes. The combined activities bring a synergy to explore how materials behave under extreme conditions, driving lattice and charge conformational changes by applying short pulses, high fields, or high pressures. The purpose of this research is to develop a world-class program on the dynamics of complex materials using the x-ray beamlines available at LCLS to address the grand challenge problems of “emergence”, non-equilibrium dynamics, and to probe model systems for deep insights on materials for energy conversion, transport and efficiency. Theoretical calculations and simulations conducted in parallel with experimental progress will help to establish a formalism for describing non-equilibrium physics of strongly correlated materials and provide additional insight to the generated experimental data. This activity requires the development of novel theoretical and computational tools and as well as the deployment of standard techniques designed to uncover the nature of the many-body state both in and out of equilibrium. We have made substantial progresses on several research fronts to advance our understanding of complex materials through advanced x-ray based techniques coupled with advanced numerical simulations. These include LCLS- and synchrotron based experiments to further the study novel quantum materials and extend knowledge of time-domain based x-ray spectroscopy. In the following, we outline our progress through lists of bullets. Progress in FY2014 Used large-scale exact diagonalization to investigate the nature of resonant inelastic x-ray scattering (RIXS) at the L-edge in cuprates, in particular the ability of RIXS to measure spin excitation in heavily-doped systems (C. J. Jia et al., Nature Communications 5, 3314 (2014) and a submission to Nature Materials). o We showed that L-edge RIXS can indeed provide a good proxy for measuring the spin dynamical structure factor which complements inelastic neutron scattering. o Utilizing quantum Monte Carlo calculations, as well as exact diagonalization, we demonstrated that even in heavily hole-doped compounds, the experimental RIXS signal indeed corresponds to persistent spin excitations at high-energies along the anti-ferromagnetic zone boundary. Our results reconcile the RIXS experiments with previous investigations using inelastic neutron and Raman techniques. o We predicted a striking asymmetry between hole- and electron-doped materials, which was recently confirmed in two separate experiments, one by members of the present FWP (arXiv:1308.4740). We have developed a microscopic understanding of lattice effects and the manifestation of electron-phonon coupling in RIXS spectra with the prospect of utilizing this technique to precisely determine the mode coupling in condensed matter systems. We have demonstrated the ability of non-resonant and resonant inelastic x-ray scattering to provide both real-space and real-time information about the flow of energy and charge in condensed matter systems. This opens the avenue Field Work Proposal – SLAC National Accelerator Laboratory Date Submitted: 6/23/2014 SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS FWP#: 10017 for a more complete mapping of charge-transfer and chemical reaction pathways using x-ray scattering techniques (Y. Wang et al, Phys. Rev. Lett. 112, 156402 (2014)). We analyzed the data taken in an experiment at LCLS, in which we studied lattice-driven striped dynamics via mid- IR pump and resonant x-ray probe on the striped nickelates. By tuning the mid-IR pump pulse to resonantly excite the breathing phonon, we observed lattice-driven striped dynamics. Surprisingly, the spin order is suppressed more than the charge order; furthermore, the recovery dynamics is notably different form that driven by optical pulse. We are now preparing a manuscript to publish these results. We analyzed the data taken in an experiment at LCLS, where we studied photo-induced dynamics in un-doped iron- pnictide, BaAs2Fe2 via optical-pump and x-ray scattering probe measurement. We observed coherent excitation of a As-Fe-As bond angle mode, which is crucial in determining the electronic structure as well as the emergence of the underlying spin density wave order. Through modeling the scattering form factor, atomic displacements during this photo-excited coherent oscillatory state can be determined. This information crucially complements other time- resolved electronic probes on the same compounds. In addition, our results indicate an intriguing temperature dependence, which might be related to the coupling with the underlying electronic fluctuations. We will perform the second measurement at the LCLS in July 2014 to confirm these observations. Experimental investigations of collective excitations in high TC-cuprates via high resolution state-of-the-art RIXS instruments worldwide. These investigations serve preparation experiments for identifying scientific cases of the later time-resolved q-RIXS experiments at the LCLS (expected in FY2016). o We have investigated the doping evolution of collective excitations in the electron-doped cuprates. Surprisingly we observed magnetic excitation hardens upon electron-doping. Furthermore, a new branch of collective modes emanating from the zone center was also observed. Our observations provide a new perspective on the issue of asymmetry in the cuprate phase diagram with respect to electron and hole- doping. We have summarize our first observation in a manuscript, which is now under review (arXiv:1308.4740). In addition, we have also performed the second measurements at the Swiss Light Source (Feb. 2014) to map out a detailed doping evolution in the phase diagram. The analysis of these new results is in progress. o We have formed new collaborations with RIXS group in National Synchrotron Radiation Research Center (NSRRC, Taiwan), where a high resolution and high throughput RIXS spectrometer with a novel AGS- AGM design is recently constructed. Using this instrument, we have performed momentum-dependent RIXS measurements on the striped cuprates La1.875Ba0.125CuO4 in April 2014. The analysis of the data is currently in progress. Technologically, evaluating the performance of such RIXS instrument is strategically important on the planning of a RIXS instrument at LCLS-II. Progress on the q-RIXS: o Two modular X-ray emission spectrographs have been fully assembled and fiducialized. They will be ready for commissioning with synchrotron beam at the ALS after the ALS shutdown is over in July 2014. o The components of third X-ray emission spectrograph have been pre-assembled and clean assembly will be carried out in summer 2014. o The components for q-RIXS endstation are arriving and the assembling will be started in summer 2014. The assembling is expected to be completed before the end of 2014. We investigated how electron-phonon coupling manifests itself in the orbital excitation profile of transition metal systems at the L-edge (J. J. Lee et al., Phys. Rev. B 89, 041104R (2014), chosen as an Editors' Suggestion). This led to a new perspective on the nature of these excitations and an explanation for the relatively large observed broadening in terms of “dressing” with lattice excitations. Field Work Proposal – SLAC National Accelerator Laboratory Date Submitted: 6/23/2014 SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS FWP#: 10017 We have utilized HPC resources both in-house at SLAC as well as those available at the National Energy Research Scientific Computing Center (NERSC). We were awarded an initial allocation of 5,000,000 CPU-hrs for FY2014 which subsequently
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