Janus Juul Eriksen
As of March 2019, my affiliation is with the University of Bristol in the group of Prof. Fred Manby where I am funded from an international postdoctoral fellowship granted by the Independent Research Fund Denmark (2019-2021). Prior to commencing work in Bristol, I have been working with Prof. Jürgen Gauss at the Johannes Gutenberg-Universität Mainz with funding from a postdoctoral fellowship granted by the Alexander von Humboldt Stiftung (2017-2019). My PhD studies (2013-2016) were conducted in the group of Prof. Poul Jørgensen at Aarhus University.
My current research is focused on a novel near-exact treatment of the electron correlation problem in quantum mechanics, as implemented in the recently proposed many-body expanded full configuration interaction (MBE-FCI) method. Previous research interests include the development of non-iterative and local coupled cluster methods as well as the high-performance computing implementation of these on standard CPU and general purpose graphics processing unit (GPU) architectures. The Research section provides additional details on past and current research interests.
24-09-2020: A new paper on “Mean-Field Density Matrix Decompositions” by Eriksen (arXiv: 2009.10837) has appeared on arXiv today. The paper introduces a new way of decomposing mean-field electronic structure theories (with applications to HF & KS-DFT) by means of localized MOs and various charge population protocols. I further demonstrate how decomposed mean-field theory makes it possible to expose and amplify compositional features in the context of machine-learned quantum chemistry.
11-08-2020: Two new papers have appeared on arXiv within the past week. In arXiv: 2008.02678 (“The Ground State Electronic Energy of Benzene” by Eriksen et al.), we report on a blind challenge devoted to the determination of the FCI ground state energy for the benzene/cc-pVDZ system, with involvement from most of the current state-of-the-art approaches from all around the world. In arXiv: 2008.03610 (“Ground and Excited State First-Order Properties in Many-Body Expanded Full Configuration Interaction Theory” by Eriksen & Gauss), MBE-FCI theory is extended to excited states and static first-order properties different from total, ground state correlation energies. Both papers have been submitted for publication.
13-07-2020: Our new paper on the PySCF program has been published in JCP: DOI: 10.1063/5.0006074
16-03-2020: My forthcoming seminar at King's College London has been cancelled/rescheduled due to COVID-19. Bummer.
02-03-2020: A new preprint on recent developments in the PySCF program package has been submitted for publication in a special issue of JCP on electronic structure software. A preprint is available on arXiv: 2002.12531.
20-02-2020 : I've been invited by George Booth @ the Department of Physics, King's College London to present a seminar on MBE-FCI theory on Tuesday, March 31st. Looking very much forward to the visit!(UPDATE 16-03-2020: Cancelled/rescheduled due to COVID-19).
13-02-2020: I am pleased to announce that our proposal for the 2020 HPC Call @ Johannes Gutenberg-Universität Mainz, Germany, has been awarded a total of 10.0M core-hours on their MogonII system. The project will be concerned with the application of our MBE-FCI method to the field of computational thermochemistry and the allocation will run for the next year.
11-12-2019: I've been invited by Nick Blunt & Alex Thom @ the Department of Chemistry, University of Cambridge to present a seminar on MBE-FCI theory on Wednesday, February 2nd next year. Looking very much forward to the visit!
27-11-2019: Our paper entitled “Generalized Many-Body Expanded Full Configuration Interaction Theory” (Eriksen & Gauss) is out now in JPCL. DOI: 10.1021/acs.jpclett.9b02968
09-10-2019: Our paper entitled “Generalized Many-Body Expanded Full Configuration Interaction Theory” (Eriksen & Gauss) has been submitted for publication. A preprint is available on arXiv: 1910.03527.
07-10-2019: The PyMBE code is now open source: https://gitlab.com/januseriksen/pymbe
09-09-2019: I'm contributing to this month's C&EN Magazine with an essay (Nomadic Tales) on my postdoctoral experience. Link: https://cen.acs.org/careers/postdocs/Postdoc-perspective-Tales-nomadic-postdoc/97/i35
05-08-2019: Our “Many-Body Expanded Full Configuration Interaction. II. Strongly Correlated Regime” (Eriksen & Gauss) paper is out now in JCTC. DOI: 10.1021/acs.jctc.9b00456
09-05-2019: Our paper entitled “Many-Body Expanded Full Configuration Interaction. II. Strongly Correlated Regime” (Eriksen & Gauss) has been submitted for publication. A preprint is available on arXiv: 1905.02786.
10-04-2019: My abstract for an oral contribution at the MQM2019 meeting (Heidelberg, Germany) later this year has been accepted. I intend to talk about recent enhancements of the MBE-FCI method and its application to increasingly larger system sizes.
27-03-2019: I am pleased to announce that my proposal for the 18th PRACE Project Access Call has been awarded a total of 26.4M core-hours on the MARCONI system @ Cineca, Bologna, Italy. The project will be concerned with the application of our MBE-FCI method to the field of computational thermochemistry and the allocation will run for the next year.
11-02-2019: After 2.5 fruitful and truly enjoyable years in Mainz, I am relocating to Bristol, UK to start a new leg of postdoctoral research by 01-03-2019, this time generously funded by the Independent Research Fund Denmark. My new host for the coming 2 years will be Prof. Fred Manby and we will work towards accelerating and enhancing the MBE-FCI method even further in continued close collaboration with Prof. Jürgen Gauss in Mainz.
22-10-2018: I will present our latest research on MBE-FCI at the Methods and Algorithms in Quantum Chemistry conference (Aarhus, Denmark), December 13-16, 2018.
20-08-2018: Our “Many-Body Expanded Full Configuration Interaction. I. Weakly Correlated Regime” (Eriksen & Gauss) paper is out now in JCTC. DOI: 10.1021/acs.jctc.8b00680
07-08-2018: I will present our latest research on MBE-FCI at the joint Mainz-Kobe workshop on Solving the Full Configuration Interaction Problem (Kobe, Japan), November 26-27, 2018.
04-07-2018: Our paper entitled “Many-Body Expanded Full Configuration Interaction. I. Weakly Correlated Regime” (Eriksen & Gauss) has been submitted for publication. A preprint is available on arXiv: 1807.01328.
01-07-2018: I will present our latest research on MBE-FCI at the Molecular Electronic Structure conference (Metz, France), August 28-31, 2018.
08-06-2018: I presented our latest research on MBE-FCI at the Low-scaling and Unconventional Electronic Structure Techniques conference (Telluride, CO, US), June 04-07, 2018.