Witnessing entanglement in a strange metal

SPICE Workshop on Quantum Matter for Quantum Technologies, May 21st - May 23rd 2024

Silke Bühler-Paschen

It is generally considered to be notoriously difficult to define, detect, or even quantify entanglement in condensed matter systems. I will discuss the potential of the “strange metal” state to make progress. Strange metal behavior – best known as a linear-in-temperature electrical resistivity at low temperatures instead of the normal Fermi liquid square-in-temperature one – occurs across many classes of quantum materials [1,2]. Its full understanding is a major challenge. Heavy fermion compounds are particularly versatile model materials for studying this physics: they are comparatively simple, clean, and highly tunable, and several characteristics beyond linear-in-temperature resistivity have already been identified. I will give an overview and highlight recent results, including dynamical scaling of the terahertz conductivity [3], strongly suppressed shot noise [4], and a quantum Fisher information analysis of inelastic neutron scattering data [5].

[1] S. Paschen, Q. Si, Nat. Rev. Phys. 3, 9 (2021).
[2] J. G. Checkelsky, B. A. Bernevig, P. Coleman, Q. Si, & S. Paschen, Nat. Rev. Mater., published online 20 February (2024).
[3] L. Prochaska et al., Science 367, 285 (2020).
[4] L. Chen et al., Science 382, 907 (2023).
[5] F. Mazza et al., arXiv:2403.12779 (2024).