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Jonas B. Profe

Publications and source records attributed to Jonas B. Profe.

21 records · Page 2Linked to original sources

Reference results for the momentum space functional renormalization group

The functional renormalization group (FRG), an established computational method for quantum many-body phenomena, has been subject to a diversification in topical applications, analytic approximations and numerical implementations. Despite significant efforts to accomplish a coherent standard through benchmarks and the reproduction of previous results, no systematic and comprehensive comparison has been provided until now. While this has not prevented the publication of relevant scientific results we argue that established mutual agreement across realizations will strengthen confidence in the method. To this end we report explicit implementational details and numerical data reproduced thrice in independent FRG implementations up to machine accuracy. To substantiate the reproducibility of our calculations we scrutinize pillar FRG results reported in the literature, and discuss our calculations of these reference systems. We mean to entice other groups to reproduce and establish this set of benchmark FRG results thus propagating the joint effort of the FRG community to engage in a shared knowledge repository as a reference standard for FRG implementations.

cond-mat.str-el↗

TU$^2$FRG -- a scalable approach for truncated unity functional renormalization group in generic fermionic models

Describing the emergence of phases of condensed matter is one of the central challenges in physics. For this purpose many numerical and analytical methods have been developed, each with their own strengths and limitations. The functional renormalization group is one of these methods bridging between efficiency and accuracy. In this paper we derive a new truncated unity (TU) approach unifying real- and momentum space TU, called TU$^2$FRG. This formalism significantly improves the scaling compared to conventional momentum (TU)FRG when applied to large unit-cell models and models where the translational symmetry is broken.

cond-mat.str-el↗

Electronic instabilities in Penrose quasi-crystals: competition, coexistence and collaboration of order

Quasicrystals lack translational symmetry, but can still exhibit long-ranged order, promoting them to candidates for unconventional physics beyond the paradigm of crystals. Here, we apply a real-space functional renormalization group approach to the prototypical quasicrystalline Penrose tiling Hubbard model treating} competing electronic instabilities in an unbiased, beyond-mean-field fashion. {\color{red} Our work reveals a delicate interplay between charge and spin degrees of freedom in quasicrystals}. Depending on the range of interactions and hopping amplitudes, we unveil a rich phase diagram including antiferromagnetic orderings, charge density waves and subleading, superconducting pairing tendencies. For certain parameter regimes we find a competition of phases, which is also common in crystals, but additionally encounter phases coexisting in a spatially separated fashion and ordering tendencies which mutually collaborate to enhance their strength. We therefore establish that quasicrystalline structures open up a route towards this rich ordering behavior uncommon to crystals and that an unbiased, beyond-mean-field approach is essential to describe this physics of quasicrystals correctly.

cond-mat.str-el↗