Gull group at the University of Warsaw

As of summer 2025, the Gull group will have openings at the Physics Department of the University of Warsaw as a part of the ERC Advanced grant Quantum Algorithms. Openings are available for postdocs, PhD students, and master students on research topics in condensed matter theory and high-performance computing, including the development of field-theoretic methods for realistic correlated electron systems and their application to systems of interest. A wide range of topics is available. Previous work (see below) provides a general overview of the research areas. The Gull group will maintain an affiliation with the University of Michigan.

Available positions

Postdoc positions

Postdocs are required to have a PhD at the time of their employment. Areas include computational and/or analytical condensed matter theory, applied mathematics, quantum chemistry, and/or high-performance computing. Experience with modern analytic or numerical methods in quantum theory is desired. Experience with numerical methods in physics and a solid foundation in code development is especially welcome.

Interested parties should contact [email protected] for information.

To apply, send your application including a cover letter, curriculum vitae, list of publications, statement of re​‐ search interests, and the three most rele​vant publi​cations in a single PDF file. Please also have two reference letters sent to this email.

For full consideration please ensure that all materials are submitted by March 25, 2025. Evaluations will continue on a rolling basis until all positions are filled.

PhD positions

Several positions for PhD candidates are available. Candidates are encouraged to contact [email protected] for information.

Master positions

Several positions for master theses for students currently enrolled at the University of Warsaw are available. Candidates are encouraged to contact [email protected] for information.

Related Work and References

Note that this subset of relevant publications is quickly outdated. For a more recent list of published work and preprints see the Google Scholar profile.

Realistic Theoretically Rigorous Electronic Structure Methods

1. Symmetry adaptation for self-consistent many-body calculations
2. Equivariant neural network for Green's functions of molecules and materials
3. Fully self-consistent finite-temperature 𝐺⁡𝑊 in Gaussian Bloch orbitals for solids
4. Relativistic self-consistent 𝐺⁡𝑊: Exact two-component formalism with one-electron approximation for solids

Quantum Impurity Solvers

1. Tensor train continuous time solver for quantum impurity models
2. Continuous-time Monte Carlo methods for quantum impurity models

Mathematical Properties of Green's Functions and Numerical Algorithms

1. Minimal pole representation and analytic continuation of matrix-valued correlation functions
2. Feynman diagrammatics based on discrete pole representations: A path to renormalized perturbation theories
3. Denoising of imaginary time response functions with Hankel projections
4. Minimal pole representation and controlled analytic continuation of Matsubara response functions
5. Robust analytic continuation of Green's functions via projection, pole estimation, and semidefinite relaxation

Application projects

1. Large exciton binding energy in a bulk van der Waals magnet from quasi-1D electronic localization
2. Ab initio self-energy embedding for the photoemission spectra of NiO and MnO

Open Source Software

1. Green/WeakCoupling: Implementation of fully self-consistent finite-temperature many-body perturbation theory for molecules and solids