Finn Lasse Buessen

Hi, I am a computational physicist with a background in quantum computing and condensed matter physics.

I earned a PhD in theoretical physics from the University of Cologne and deepened my research expertise for several years as a postdoctoral fellow at the University of Toronto. I am now pursuing my interests in the quantum computing industry. You can meet me on LinkedIn or learn more about my work on Github or Google Scholar.

I am passionate about the development of elegant code that pushes the limits of modern computational science, drawing on my expertise in software development and high-performance computing. I firmly believe that scientific software should be sustainable and outlive its original scientific context of creation. Only then can it serve as a catalyst to accelerate research in a time where state-of-the-art computational algorithms can sometimes be intimidatingly complex to implement.

One showcase of my work is the SpinParser project [SciPost Phys. Codebases 5 (2022)] that enables researchers around the world to perform highly efficient functional renormalization group studies on quantum magnetism, with code written in modern C++ and capable of leveraging high-performance computing platforms with thousands of compute cores. I have also published a versatile Monte Carlo package in the Julia programming language, SpinMC.jl, that is tailored to advance research on classical frustrated magnetism and has lead to numerous publications in the field.



Finn Lasse Buessen, Dvira Segal, and Ilia Khait

Simulating time evolution on distributed quantum computers

Physical Review Research 5, L022003 (2023)


Finn Lasse Buessen, Hyun-Yong Lee, Tarun Grover, and Yong Baek Kim

Pre-thermalization via self-driving and external driving of extensive subsystems

Physical Review B 106, 174417 (2022)

Jackson Pitts, Finn Lasse Buessen, Roderich Moessner, Simon Trebst, and Kirill Shtengel

Order by disorder in classical kagome antiferromagnets with chiral interactions

Physical Review Research 4, 043019 (2022)

Finn Lasse Buessen

The SpinParser software for pseudofermion functional renormalization group calculations on quantum magnets

SciPost Physics Codebases 5 (2022)

Finn Lasse Buessen

Codebase release 1.0 for SpinParser

SciPost Physics Codebases 5-r1.0 (2022)

P. Padmanabhan, F.L. Buessen, R. Tutchton, K.W.C. Kwock, S. Gilinsky, M.C. Lee, M.A. McGuire, S.R. Singamaneni, D.A. Yarotski, A. Paramekanti, J.-X. Zhu, R.P. Prasankumar

Coherent Helicity-Dependent Spin-Phonon Oscillations in the Ferromagnetic van der Waals Crystal CrI3

Nature Communications 13, 4473 (2022)

Subhadeep Bandyopadhyay, Finn Lasse Buessen, Ritwik Das, Franz G. Utermohlen, Nandini Trivedi, Arun Paramekanti, and Indra Dasgupta

Exchange interactions and spin dynamics in the layered honeycomb ferromagnet CrI3

Physical Review B 105, 184430 (2022)

Emily Z. Zhang, Finn Lasse Buessen, and Yong Baek Kim

Dynamical signatures of rank-2 U(1) spin liquids

Physical Review B 105, L060408 (2022)


Finn Lasse Buessen and Yong Baek Kim

Functional renormalization group study of the Kitaev-Gamma model on the honeycomb lattice and emergent incommensurate magnetic correlations

Physical Review B 103, 184407 (2021)

Finn Lasse Buessen, Sopheak Sorn, Ivar Martin, and Arun Paramekanti

Nematic order driven by superconducting correlations

Annals of Physics 435, 168494 (2021) [arXiv:2101.03174]

Nazim Boudjada, Finn Lasse Buessen, and Arun Paramekanti

Molecular dipoles in designer honeycomb lattices

Physical Review B 103, 165408 (2021)

Li Ern Chern, Finn Lasse Buessen, and Yong Baek Kim

Classical magnetic vortex liquid and large thermal Hall conductivity in frustrated magnets with bond-dependent interactions

npj Quantum Materials 6, 33 (2021)


A. Revelli, M. Moretti Sala, G. Monaco, C. Hickey, P. Becker, F. Freund, A. Jesche, P. Gegenwart, T. Eschmann, F.L. Buessen, S. Trebst, P.H.M. van Loosdrecht, J. van den Brink, and M. Grüninger

Fingerprints of Kitaev physics in the magnetic excitations of honeycomb iridates

Physical Review Research 2, 043094 (2020)

Nazim Boudjada, Finn Lasse Buessen, and Arun Paramekanti

Domes of Tc in superconductors with finite-range attractive interactions

Physical Review B 102, 054504 (2020)

Dominik Kiese, Finn Lasse Buessen, Ciarán Hickey, Simon Trebst, and Michael M. Scherer

Emergence and stability of spin-valley entangled quantum liquids in moiré heterostructures

Physical Review Research 2, 013370 (2020)


Finn Lasse Buessen

A Functional Renormalization Group Perspective on Quantum Spin Liquids in Three-Dimensional Frustrated Magnets

Ph.D. thesis, University of Cologne (2019)

Finn Lasse Buessen, Vincent Noculak, Simon Trebst, and Johannes Reuther

Functional renormalization group for frustrated magnets with nondiagonal spin interactions

Physical Review B 100, 125164 (2019)

A. Revelli, C.C. Loo, D. Kiese, P. Becker, T. Fröhlich, T. Lorenz, M. Moretti Sala, G. Monaco, F.L. Buessen, J. Attig, M. Hermanns, S.V. Streltsov, D.I. Khomskii, J. van den Brink, M. Braden, P.H.M. van Loosdrecht, S. Trebst, A. Paramekanti, and M. Grüninger

Spin-orbit entangled j=1/2 moments in Ba2CeIrO6: A frustrated fcc quantum magnet

Physical Review B 100, 085139 (2019)


Finn Lasse Buessen, Max Hering, Johannes Reuther, and Simon Trebst

Quantum spin liquids in frustrated spin-1 diamond antiferromagnets

Physical Review Letters 120, 057201 (2018)

Finn Lasse Buessen, Dietrich Roscher, Sebastian Diehl, and Simon Trebst

Functional renormalization group approach to SU(N) Heisenberg models: Real-space RG at arbitrary N

Physical Review B 97, 064415 (2018)

Dietrich Roscher, Finn Lasse Buessen, Michael M. Scherer, Simon Trebst, and Sebastian Diehl

Functional renormalization group approach to SU(N) Heisenberg models: Momentum-space RG for the large-N limit

Physical Review B 97, 064416 (2018)


Finn Lasse Buessen and Simon Trebst

Competing magnetic orders and spin liquids in two- and three-dimensional kagome systems: Pseudo-fermion functional renormalization group perspective

Physical Review B 94, 235138 (2016)

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