TY - JOUR
AU - Altenkort, Luis
AU - Eller, Alexander M.
AU - Kaczmarek, O.
AU - Mazur, Lukas
AU - Moore, Guy D.
AU - Shu, Hai-Tao
ID - 46121
IS - 9
JF - Physical Review D
SN - 2470-0010
TI - Lattice QCD noise reduction for bosonic correlators through blocking
VL - 105
ER -
TY - GEN
AB - Electronic structure calculations have been instrumental in providing many
important insights into a range of physical and chemical properties of various
molecular and solid-state systems. Their importance to various fields,
including materials science, chemical sciences, computational chemistry and
device physics, is underscored by the large fraction of available public
supercomputing resources devoted to these calculations. As we enter the
exascale era, exciting new opportunities to increase simulation numbers, sizes,
and accuracies present themselves. In order to realize these promises, the
community of electronic structure software developers will however first have
to tackle a number of challenges pertaining to the efficient use of new
architectures that will rely heavily on massive parallelism and hardware
accelerators. This roadmap provides a broad overview of the state-of-the-art in
electronic structure calculations and of the various new directions being
pursued by the community. It covers 14 electronic structure codes, presenting
their current status, their development priorities over the next five years,
and their plans towards tackling the challenges and leveraging the
opportunities presented by the advent of exascale computing.
AU - Gavini, Vikram
AU - Baroni, Stefano
AU - Blum, Volker
AU - Bowler, David R.
AU - Buccheri, Alexander
AU - Chelikowsky, James R.
AU - Das, Sambit
AU - Dawson, William
AU - Delugas, Pietro
AU - Dogan, Mehmet
AU - Draxl, Claudia
AU - Galli, Giulia
AU - Genovese, Luigi
AU - Giannozzi, Paolo
AU - Giantomassi, Matteo
AU - Gonze, Xavier
AU - Govoni, Marco
AU - Gulans, Andris
AU - Gygi, François
AU - Herbert, John M.
AU - Kokott, Sebastian
AU - Kühne, Thomas
AU - Liou, Kai-Hsin
AU - Miyazaki, Tsuyoshi
AU - Motamarri, Phani
AU - Nakata, Ayako
AU - Pask, John E.
AU - Plessl, Christian
AU - Ratcliff, Laura E.
AU - Richard, Ryan M.
AU - Rossi, Mariana
AU - Schade, Robert
AU - Scheffler, Matthias
AU - Schütt, Ole
AU - Suryanarayana, Phanish
AU - Torrent, Marc
AU - Truflandier, Lionel
AU - Windus, Theresa L.
AU - Xu, Qimen
AU - Yu, Victor W. -Z.
AU - Perez, Danny
ID - 33493
T2 - arXiv:2209.12747
TI - Roadmap on Electronic Structure Codes in the Exascale Era
ER -
TY - CONF
AU - Karp, Martin
AU - Podobas, Artur
AU - Kenter, Tobias
AU - Jansson, Niclas
AU - Plessl, Christian
AU - Schlatter, Philipp
AU - Markidis, Stefano
ID - 46193
T2 - International Conference on High Performance Computing in Asia-Pacific Region
TI - A High-Fidelity Flow Solver for Unstructured Meshes on Field-Programmable Gate Arrays: Design, Evaluation, and Future Challenges
ER -
TY - GEN
AB - The CP2K program package, which can be considered as the swiss army knife of
atomistic simulations, is presented with a special emphasis on ab-initio
molecular dynamics using the second-generation Car-Parrinello method. After
outlining current and near-term development efforts with regards to massively
parallel low-scaling post-Hartree-Fock and eigenvalue solvers, novel approaches
on how we plan to take full advantage of future low-precision hardware
architectures are introduced. Our focus here is on combining our submatrix
method with the approximate computing paradigm to address the immanent exascale
era.
AU - Kühne, Thomas
AU - Plessl, Christian
AU - Schade, Robert
AU - Schütt, Ole
ID - 32404
T2 - arXiv:2205.14741
TI - CP2K on the road to exascale
ER -
TY - JOUR
AB - A parallel hybrid quantum-classical algorithm for the solution of the quantum-chemical ground-state energy problem on gate-based quantum computers is presented. This approach is based on the reduced density-matrix functional theory (RDMFT) formulation of the electronic structure problem. For that purpose, the density-matrix functional of the full system is decomposed into an indirectly coupled sum of density-matrix functionals for all its subsystems using the adaptive cluster approximation to RDMFT. The approximations involved in the decomposition and the adaptive cluster approximation itself can be systematically converged to the exact result. The solutions for the density-matrix functionals of the effective subsystems involves a constrained minimization over many-particle states that are approximated by parametrized trial states on the quantum computer similarly to the variational quantum eigensolver. The independence of the density-matrix functionals of the effective subsystems introduces a new level of parallelization and allows for the computational treatment of much larger molecules on a quantum computer with a given qubit count. In addition, for the proposed algorithm techniques are presented to reduce the qubit count, the number of quantum programs, as well as its depth. The evaluation of a density-matrix functional as the essential part of our approach is demonstrated for Hubbard-like systems on IBM quantum computers based on superconducting transmon qubits.
AU - Schade, Robert
AU - Bauer, Carsten
AU - Tamoev, Konstantin
AU - Mazur, Lukas
AU - Plessl, Christian
AU - Kühne, Thomas
ID - 33226
JF - Phys. Rev. Research
TI - Parallel quantum chemistry on noisy intermediate-scale quantum computers
VL - 4
ER -
TY - GEN
AB - Electronic structure calculations have been instrumental in providing many
important insights into a range of physical and chemical properties of various
molecular and solid-state systems. Their importance to various fields,
including materials science, chemical sciences, computational chemistry and
device physics, is underscored by the large fraction of available public
supercomputing resources devoted to these calculations. As we enter the
exascale era, exciting new opportunities to increase simulation numbers, sizes,
and accuracies present themselves. In order to realize these promises, the
community of electronic structure software developers will however first have
to tackle a number of challenges pertaining to the efficient use of new
architectures that will rely heavily on massive parallelism and hardware
accelerators. This roadmap provides a broad overview of the state-of-the-art in
electronic structure calculations and of the various new directions being
pursued by the community. It covers 14 electronic structure codes, presenting
their current status, their development priorities over the next five years,
and their plans towards tackling the challenges and leveraging the
opportunities presented by the advent of exascale computing.
AU - Gavini, Vikram
AU - Baroni, Stefano
AU - Blum, Volker
AU - Bowler, David R.
AU - Buccheri, Alexander
AU - Chelikowsky, James R.
AU - Das, Sambit
AU - Dawson, William
AU - Delugas, Pietro
AU - Dogan, Mehmet
AU - Draxl, Claudia
AU - Galli, Giulia
AU - Genovese, Luigi
AU - Giannozzi, Paolo
AU - Giantomassi, Matteo
AU - Gonze, Xavier
AU - Govoni, Marco
AU - Gulans, Andris
AU - Gygi, François
AU - Herbert, John M.
AU - Kokott, Sebastian
AU - Kühne, Thomas
AU - Liou, Kai-Hsin
AU - Miyazaki, Tsuyoshi
AU - Motamarri, Phani
AU - Nakata, Ayako
AU - Pask, John E.
AU - Plessl, Christian
AU - Ratcliff, Laura E.
AU - Richard, Ryan M.
AU - Rossi, Mariana
AU - Schade, Robert
AU - Scheffler, Matthias
AU - Schütt, Ole
AU - Suryanarayana, Phanish
AU - Torrent, Marc
AU - Truflandier, Lionel
AU - Windus, Theresa L.
AU - Xu, Qimen
AU - Yu, Victor W. -Z.
AU - Perez, Danny
ID - 46275
T2 - arXiv:2209.12747
TI - Roadmap on Electronic Structure Codes in the Exascale Era
ER -
TY - JOUR
AU - Schade, Robert
AU - Kenter, Tobias
AU - Elgabarty, Hossam
AU - Lass, Michael
AU - Schütt, Ole
AU - Lazzaro, Alfio
AU - Pabst, Hans
AU - Mohr, Stephan
AU - Hutter, Jürg
AU - Kühne, Thomas
AU - Plessl, Christian
ID - 33684
JF - Parallel Computing
KW - Artificial Intelligence
KW - Computer Graphics and Computer-Aided Design
KW - Computer Networks and Communications
KW - Hardware and Architecture
KW - Theoretical Computer Science
KW - Software
SN - 0167-8191
TI - Towards electronic structure-based ab-initio molecular dynamics simulations with hundreds of millions of atoms
VL - 111
ER -
TY - JOUR
AU - Meyer, Marius
AU - Kenter, Tobias
AU - Plessl, Christian
ID - 27364
JF - Journal of Parallel and Distributed Computing
SN - 0743-7315
TI - In-depth FPGA Accelerator Performance Evaluation with Single Node Benchmarks from the HPC Challenge Benchmark Suite for Intel and Xilinx FPGAs using OpenCL
ER -
TY - JOUR
AB - Recent advances in numerical methods significantly pushed forward the
understanding of electrons coupled to quantized lattice vibrations. At this
stage, it becomes increasingly important to also account for the effects of
physically inevitable environments. In particular, we study the transport
properties of the Hubbard-Holstein Hamiltonian that models a large class of
materials characterized by strong electron-phonon coupling, in contact with a
dissipative environment. Even in the one-dimensional and isolated case,
simulating the quantum dynamics of such a system with high accuracy is very
challenging due to the infinite dimensionality of the phononic Hilbert spaces.
For this reason, the effects of dissipation on the conductance properties of
such systems have not been investigated systematically so far. We combine the
non-Markovian hierarchy of pure states method and the Markovian quantum jumps
method with the newly introduced projected purified density-matrix
renormalization group, creating powerful tensor-network methods for dissipative
quantum many-body systems. Investigating their numerical properties, we find a
significant speedup up to a factor $\sim 30$ compared to conventional
tensor-network techniques. We apply these methods to study dissipative
quenches, aiming for an in-depth understanding of the formation, stability, and
quasi-particle properties of bipolarons. Surprisingly, our results show that in
the metallic phase dissipation localizes the bipolarons, which is reminiscent
of an indirect quantum Zeno effect. However, the bipolaronic binding energy
remains mainly unaffected, even in the presence of strong dissipation,
exhibiting remarkable bipolaron stability. These findings shed light on the
problem of designing real materials exhibiting phonon-mediated
high-$T_\mathrm{C}$ superconductivity.
AU - Moroder, Mattia
AU - Grundner, Martin
AU - Damanet, François
AU - Schollwöck, Ulrich
AU - Mardazad, Sam
AU - Flannigan, Stuart
AU - Köhler, Thomas
AU - Paeckel, Sebastian
ID - 50146
JF - Physical Review B 107, 214310 (2023)
TI - Stable bipolarons in open quantum systems
ER -
TY - JOUR
AB - We develop a general decomposition of an ensemble of initial density profiles
in terms of an average state and a basis of modes that represent the
event-by-event fluctuations of the initial state. The basis is determined such
that the probability distributions of the amplitudes of different modes are
uncorrelated. Based on this decomposition, we quantify the different types and
probabilities of event-by-event fluctuations in Glauber and Saturation models
and investigate how the various modes affect different characteristics of the
initial state. We perform simulations of the dynamical evolution with KoMPoST
and MUSIC to investigate the impact of the modes on final-state observables and
their correlations.
AU - Borghini, Nicolas
AU - Borrell, Marc
AU - Feld, Nina
AU - Roch, Hendrik
AU - Schlichting, Sören
AU - Werthmann, Clemens
ID - 50148
JF - Phys. Rev. C 107 (2023) 034905
TI - Statistical analysis of initial state and final state response in heavy-ion collisions
ER -
TY - JOUR
AB - Abstract
RNA editing processes are strikingly different in animals and plants. Up to thousands of specific cytidines are converted into uridines in plant chloroplasts and mitochondria whereas up to millions of adenosines are converted into inosines in animal nucleo-cytosolic RNAs. It is unknown whether these two different RNA editing machineries are mutually incompatible. RNA-binding pentatricopeptide repeat (PPR) proteins are the key factors of plant organelle cytidine-to-uridine RNA editing. The complete absence of PPR mediated editing of cytosolic RNAs might be due to a yet unknown barrier that prevents its activity in the cytosol. Here, we transferred two plant mitochondrial PPR-type editing factors into human cell lines to explore whether they could operate in the nucleo-cytosolic environment. PPR56 and PPR65 not only faithfully edited their native, co-transcribed targets but also different sets of off-targets in the human background transcriptome. More than 900 of such off-targets with editing efficiencies up to 91%, largely explained by known PPR-RNA binding properties, were identified for PPR56. Engineering two crucial amino acid positions in its PPR array led to predictable shifts in target recognition. We conclude that plant PPR editing factors can operate in the entirely different genetic environment of the human nucleo-cytosol and can be intentionally re-engineered towards new targets.
AU - Lesch, Elena
AU - Schilling, Maximilian T
AU - Brenner, Sarah
AU - Yang, Yingying
AU - Gruss, Oliver J
AU - Knoop, Volker
AU - Schallenberg-Rüdinger, Mareike
ID - 50149
IS - 17
JF - Nucleic Acids Research
KW - Genetics
SN - 0305-1048
TI - Plant mitochondrial RNA editing factors can perform targeted C-to-U editing of nuclear transcripts in human cells
VL - 50
ER -
TY - JOUR
AB - N-body methods are one of the essential algorithmic building blocks of high-performance and parallel computing. Previous research has shown promising performance for implementing n-body simulations with pairwise force calculations on FPGAs. However, to avoid challenges with accumulation and memory access patterns, the presented designs calculate each pair of forces twice, along with both force sums of the involved particles. Also, they require large problem instances with hundreds of thousands of particles to reach their respective peak performance, limiting the applicability for strong scaling scenarios. This work addresses both issues by presenting a novel FPGA design that uses each calculated force twice and overlaps data transfers and computations in a way that allows to reach peak performance even for small problem instances, outperforming previous single precision results even in double precision, and scaling linearly over multiple interconnected FPGAs. For a comparison across architectures, we provide an equally optimized CPU reference, which for large problems actually achieves higher peak performance per device, however, given the strong scaling advantages of the FPGA design, in parallel setups with few thousand particles per device, the FPGA platform achieves highest performance and power efficiency.
AU - Menzel, Johannes
AU - Plessl, Christian
AU - Kenter, Tobias
ID - 28099
IS - 1
JF - ACM Transactions on Reconfigurable Technology and Systems
SN - 1936-7406
TI - The Strong Scaling Advantage of FPGAs in HPC for N-body Simulations
VL - 15
ER -
TY - CONF
AU - Meyer, Marius
ID - 27365
T2 - Proceedings of the 11th International Symposium on Highly Efficient Accelerators and Reconfigurable Technologies
TI - Towards Performance Characterization of FPGAs in Context of HPC using OpenCL Benchmarks
ER -
TY - CONF
AU - Nickchen, Tobias
AU - Heindorf, Stefan
AU - Engels, Gregor
ID - 20886
T2 - Proceedings of the IEEE/CVF Winter Conference on Applications of Computer Vision
TI - Generating Physically Sound Training Data for Image Recognition of Additively Manufactured Parts
ER -
TY - JOUR
AB - Abstract
The defining feature of active particles is that they constantly propel themselves by locally converting chemical energy into directed motion. This active self-propulsion prevents them from equilibrating with their thermal environment (e.g. an aqueous solution), thus keeping them permanently out of equilibrium. Nevertheless, the spatial dynamics of active particles might share certain equilibrium features, in particular in the steady state. We here focus on the time-reversal symmetry of individual spatial trajectories as a distinct equilibrium characteristic. We investigate to what extent the steady-state trajectories of a trapped active particle obey or break this time-reversal symmetry. Within the framework of active Ornstein–Uhlenbeck particles we find that the steady-state trajectories in a harmonic potential fulfill path-wise time-reversal symmetry exactly, while this symmetry is typically broken in anharmonic potentials.
AU - Dabelow, Lennart
AU - Bo, Stefano
AU - Eichhorn, Ralf
ID - 32243
IS - 3
JF - Journal of Statistical Mechanics: Theory and Experiment
KW - Statistics
KW - Probability and Uncertainty
KW - Statistics and Probability
KW - Statistical and Nonlinear Physics
SN - 1742-5468
TI - How irreversible are steady-state trajectories of a trapped active particle?
VL - 2021
ER -
TY - GEN
AB - We push the boundaries of electronic structure-based \textit{ab-initio}
molecular dynamics (AIMD) beyond 100 million atoms. This scale is otherwise
barely reachable with classical force-field methods or novel neural network and
machine learning potentials. We achieve this breakthrough by combining
innovations in linear-scaling AIMD, efficient and approximate sparse linear
algebra, low and mixed-precision floating-point computation on GPUs, and a
compensation scheme for the errors introduced by numerical approximations. The
core of our work is the non-orthogonalized local submatrix method (NOLSM),
which scales very favorably to massively parallel computing systems and
translates large sparse matrix operations into highly parallel, dense matrix
operations that are ideally suited to hardware accelerators. We demonstrate
that the NOLSM method, which is at the center point of each AIMD step, is able
to achieve a sustained performance of 324 PFLOP/s in mixed FP16/FP32 precision
corresponding to an efficiency of 67.7% when running on 1536 NVIDIA A100 GPUs.
AU - Schade, Robert
AU - Kenter, Tobias
AU - Elgabarty, Hossam
AU - Lass, Michael
AU - Schütt, Ole
AU - Lazzaro, Alfio
AU - Pabst, Hans
AU - Mohr, Stephan
AU - Hutter, Jürg
AU - Kühne, Thomas D.
AU - Plessl, Christian
ID - 32244
T2 - arXiv:2104.08245
TI - Towards Electronic Structure-Based Ab-Initio Molecular Dynamics Simulations with Hundreds of Millions of Atoms
ER -
TY - GEN
AB - Optical travelling wave antennas offer unique opportunities to control and
selectively guide light into a specific direction which renders them as
excellent candidates for optical communication and sensing. These applications
require state of the art engineering to reach optimized functionalities such as
high directivity and radiation efficiency, low side lobe level, broadband and
tunable capabilities, and compact design. In this work we report on the
numerical optimization of the directivity of optical travelling wave antennas
made from low-loss dielectric materials using full-wave numerical simulations
in conjunction with a particle swarm optimization algorithm. The antennas are
composed of a reflector and a director deposited on a glass substrate and an
emitter placed in the feed gap between them serves as an internal source of
excitation. In particular, we analysed antennas with rectangular- and
horn-shaped directors made of either Hafnium dioxide or Silicon. The optimized
antennas produce highly directional emission due to the presence of two
dominant guided TE modes in the director in addition to leaky modes. These
guided modes dominate the far-field emission pattern and govern the direction
of the main lobe emission which predominately originates from the end facet of
the director. Our work also provides a comprehensive analysis of the modes,
radiation patterns, parametric influences, and bandwidths of the antennas that
highlights their robust nature.
AU - Farheen, Henna
AU - Leuteritz, Till
AU - Linden, Stefan
AU - Myroshnychenko, Viktor
AU - Förstner, Jens
ID - 32245
T2 - arXiv:2106.02468
TI - Optimization of optical waveguide antennas for directive emission of light
ER -
TY - GEN
AB - The interaction between quantum light and matter is being intensively studied
for systems that are enclosed in high-$Q$ cavities which strongly enhance the
light-matter coupling. However, for many applications, cavities with lower
$Q$-factors are preferred due to the increased spectral width of the cavity
mode. Here, we investigate the interaction between quantum light and matter
represented by a $\Lambda$-type three-level system in lossy cavities, assuming
that cavity losses are the dominant loss mechanism. We demonstrate that cavity
losses lead to non-trivial steady states of the electronic occupations that can
be controlled by the loss rate and the initial statistics of the quantum
fields. The mechanism of formation of such steady states can be understood on
the basis of the equations of motion. Analytical expressions for steady states
and their numerical simulations are presented and discussed.
AU - Rose, H.
AU - Tikhonova, O. V.
AU - Meier, T.
AU - Sharapova, P.
ID - 32236
T2 - arXiv:2109.00842
TI - Steady states of $Λ$-type three-level systems excited by quantum light in lossy cavities
ER -
TY - JOUR
AU - Kaczmarek, Olaf
AU - Mazur, Lukas
AU - Sharma, Sayantan
ID - 46122
IS - 9
JF - Physical Review D
SN - 2470-0010
TI - Eigenvalue spectra of QCD and the fate of UA(1) breaking towards the chiral limit
VL - 104
ER -
TY - JOUR
AU - Altenkort, Luis
AU - Eller, Alexander M.
AU - Kaczmarek, O.
AU - Mazur, Lukas
AU - Moore, Guy D.
AU - Shu, H.-T.
ID - 46124
IS - 1
JF - Physical Review D
SN - 2470-0010
TI - Heavy quark momentum diffusion from the lattice using gradient flow
VL - 103
ER -