Speaker
Description
Studies of low-temperature ordering in long-range interacting many-particle systems continue to attract significant interest. While such systems are common in nature, some features of their critical behavior remain unexplained. We address the combined impact of weak structural disorder and weak long-range interactions decaying in $d$-dimensional space as $x^{-d-\sigma}$ with $\sigma > 0$ on the critical behavior of classical model with $n$-component spins. Whithin specific regions of the parameter space $(n, d, \sigma)$, this model exibits a distinct disorder-induced long-range universality class. To characterize this universality class we calculate the marginal dimensions [1] and scaling exponents [2,3] governing the system's criticality within the three-loop approximation of field-theoretical renormalization group approach. Furthermore, we present refined estimates of these universal quantities by applying resummation techniques to the divergent perturbation series.
M.D. and D.S. acknowledge support of the U. S. Department of Energy (DOE), Office of Science, Basic Energy Sciences, Materials Science and Engineering Division, under Award No. DE–SC0013599
[1] D. Shapoval, M. Dudka, Yu. Holovatch, Low Temp. Phys. $\textbf{48}$ (2022) 1049.
[2] M. Dudka, D. Shapoval, Yu. Holovatch, Journal of Physical Studies $\textbf{28}$ (2024) 2601.
[3] D. Shapoval, M. Dudka, Condens. Matter Phys. $\textbf{28}$ (2025) 43503.
