Computer programs and utilities developed

Several XLIC theoretical groups have worked in the development of new computer codes or improvement of existing ones. Collaborations among them have allowed to extend their application to new problems and to the interpretation of new experiments done in the framework of the XLIC Action. Some of these groups and their results are listed below
(the list does not intend to be exhaustive, but gives an idea of the most important programs developed in the Action and their range of applications):

L. Gonzalez group, at the University of Vienna (AT), are the developers of the SHARC code (Surface Hopping including ARbitrary Couplings), www.sharc-md.org. A new version, able to calculate ionization yield (Dyson norms), shall be released soon.

– M. Barbati group, at Aix Marseille University (FR), is the developer of the Newton-X code http://newtonx.org.

– P. Decleva, at University of Trieste (IT), is an expert in methods and software for the study of the dynamic of photoemission and photoabsorption processes of atoms and molecules both as concerns the discrete states and the electronic continuum. During XLIC Action, he has worked on the:

  1. Implementation of photoionization from dyson orbitals within the B-spline molecular continuum code, see J. Chem Phys., 140 (2014) 204304 and J. Chem Phys., 144 (2016) 084307.
  2. Implementation of a time propagation routine based on Arnoldi-Lanczos algorithm interfaced with the B-spline molecular code
  3. Implementation of a molecular wavepacket projection code onto numerical continuum states, for the calculation of energy and angle resolved photoelectron spectra (testing phase) interfaced with the B-spline molecular code

F. Martin group, at Universidad Autonoma de Madrid (ES), develops state-of-the-art time-dependent methods to address newly emerging questions about the role of sub-fs and attosecond coherent electron dynamics in chemical reactivity.
His group has developed the XCHEM code (https://www.xchem.uam.es), a hybrid-basis close-coupling interface to quantum chemistry packages for the treatment of ionization problems. Its outputs may be of value to the physics and chemistry community, and it is expected that they may enable the simulation of relevant processes in the time-domain. Its release its expected in less than two years.

J.D. Gorfinkel group, at the Open University (UK), developments of a set of high-quality, user-friendly codes to treat both electron photon interactions with polyatomic molecules using the R-matrix method. See UKRMol-in and UKRMol-out.

A. Scrinzi group, at the Ludwig-Maximilians-Universität (DE), works on MCTDHF and time dependent surface flux (t-SURFF) methods. He has developed the The tRecX code (https://trecx.physik.lmu.de/), a solver for the time-dependent Schroedinger equation of atoms and molecules in the presence of strong fields.

O. Smirnova group, at MBI Berlin (DE), develops programs for time- and space-resolved imaging and control of charge migration, electron rearrangement, autoionization and coupling of the electronic and vibrational motions in molecules.

B. Piraux, at the Univ. Catholique de Louvain (BE), is an expert in light-matter interaction under strong fields.

P. O`Mahony and F. Mota-Furtado, at Royal Holloway, University of London, in cooperation with B. Piraux, have have developed a range of computer programs to solve the time dependent Schrödinger equation (TDSE) in an intense laser field. These ranged from new time integration methods such as the time scaled co-ordinate technique and Fatunla’s method to using basis sets of Sturmian function to solve Faddeev like inhomogeneous equations to compare with the strong field approximation.  In addition a general code using Sturmian bases and complex scaling to treat the TDSE with arbitrary laser polarisation has been developed.

H. Van der Hart, at Queen’s Univ. of Belfast (UK), works in light-matter interaction under intense laser fields using time-dependent R-matrix methods

D. Dundas group, at the Atomistic Simulation Centre, QUB (UK), has developed two Two computer programs/libraries:

  1. EDAMAME (Ehrenfest DynAMics on Adaptive MEshes), a parallel code that solves the time-dependent Kohn-Sham equations of time-dependent density functional theory to describe complex molecules irradiated by intense, short-duration laser pulses. For more information see http://titus.phy.qub.ac.uk/packages/EDAMAME
  2. POpSiCLE (PhOtoelectron SpeCtrum library for Laser-matter intEractions), a library of functions that was developed in order to calculate photoelectron spectra by analysing the ionizing wavepackets. More information: https://ccpforge.cse.rl.ac.uk/gf/project/popsicle/.

A. Rubio (MPSD  Hamburg and EHU, San Sebastian Spain) and A. Castro (U. Zaragoza . Spain) are developers of the Octopus code (http://octopus-code.org/wiki/Main_Page).

G. Worth group, at Birmingham University, are the developers of the Quantics code for nuclear wavepacket dynamics on the femtosecond timescale based on the MCTDH algorithm. http://www.stchem.bham.ac.uk/~quantics/. Further developments have been carried out during the Action. Main author is Graham Worth (now at UCL).

I. Sola, at the Complutense University in Madrid has participated the development of the SHARC scheme. His group has developed a code of local-control theory for electron-nuclear dynamics in cooperation with Chris Meier (Université Paul Sabatier, Toulouse). See Chem. Phys. 478, 97 (2016) 97-102, and a code for a method called Geometrical Optimization (variational optimization in a Hilbert space that implies subsystems arranged in manifolds). See J. Phys. Chem. Lett. 6, 1724 (2015); J. Chem. Theory and Comput. 11, 4005 (2015); J. Phys. Chem. A 119, 9091 (2015); Phys. Chem. Chem. Phys. 18, 13443 (2016); Phys. Chem. Chem. Phys. 18, 25265 (2016).

K. Tokesi has developed, in collaboration with J. Burgdorfer, L. Nagy, S. Nagele and J. Feist, a classical trajectory Monte Carlo code to study laser-atom collisions (see Phys. Rev. A 90 (2014) 052706) and a classical transport code for mimic the streaking image in collaboration with C. Lemell and J. Burgdorfer (see Phys. Rev. B: Rapid Communication, 91 (2015) 241101(R))

L. Nikolopoulos, at the School of Physical Sciences, Ireland, has developed the code CLTDSE, a General-purpose computing on graphics processing units (GPGPU) based computational program and framework for the electronic dynamics of atomic systems under intense laser fields. It is the first available GPGPU based implementation of the Taylor, Runge–Kutta and Lanczos based methods created with strong field ab-initio simulations specifically in mind.

Two of the groups work in companies

I. Tavernelli (IBM-Zurich, CH) is the main developer of the TD-DFT implementation in CPMD. IBM-Zurich coordinates the development of the CPDM code http://www.cpmd.org.

SCM (Scientific Computing & Modelling) is a company that develop the ADF Modelling Suite https://www.scm.com/

 

The importance of the XLIC Action has been to act as a forum where developers of different codes can exchange their expertise. Many collaborations exist among the above mentioned groups, that are leading to a fast development of new methods and codes dealing with the description of electronic and nuclear dynamic in the presence of laser fields.

At least 68 STSM were related with the exchange of expertise among theoretical groups.