The JCMS series

The Joint Condensed Matter Seminar (JCMS) series is organised by KTH Royal Insitute of Technology, Nordita, and Stockholm University.

February 25th, 2025: Nicolo Defenu

On Tuesday, February 25th, 2025 from 14.15 to 15.15 we will host a seminar by Nicolo Defenu from ETH Zurich.

Title

Tuneable universality for quantum technology

Abstract

The concept of universality has profoundly influenced our understanding of many-body physics, primarily within homogeneous systems, where the scaling of lattice systems can be described by continuous $\varphi^{4}$-theories in integer Euclidean dimension. In this talk, we explore universality on a non-homogeneous graph, specifically the long-range diluted graph (LRDG). Our analysis reveals that the scaling theory of such systems is governed by a single parameter, the spectral dimension $d_{s}$, which acts as the control parameter in complex geometries. The LRDG enables continuous tuning of the spectral dimension to both integer and non-integer values, allowing us to determine universal exponents as continuous functions of the dimension. The importance of having tuneable universal scaling in quantum technology will be also discussed.