Physics Paradigm Challenge

We finally might have solved the mystery of 'strange metals'—turns out there was just a normal metal hiding inside them the whole time.

March 26, 2026

Original Paper

Reconciling strange metal transport in CeCoIn$_5$ through the difference of optical and cyclotron effective masses

Jingyuan Wang, Zhenisbek Tagay, Liyu Shi, Jiahao Liang, Nghiep Khoan Duong, Yi Wu, P.M.T. Vianez, F. Ronning, D.G. Rickel, Darrell G. Schlom, K.M. Shen, S.A. Crooker, N.P. Armitage

arXiv · 2603.23740

The Takeaway

Strange metals have long baffled scientists because their electrical resistance changes in a way that seems to break the laws of physics. This experiment reveals that the electrons are actually behaving normally, but they appear strange because their mass increases with temperature, masking a 'hidden' normal metal state.

From the abstract

The strange metal behavior in cuprate superconductors - characterized by linear in temperature resistivity and anomalous Hall transport - stands in stark contrast to the expectation of conventional Fermi liquid (FL) theory. Remarkably, the similar transport behavior has also been observed in the heavy fermion metal CeCoIn$_5$, whose d-wave superconducting ground state and strong antiferromagnetic fluctuations draw parallels to the cuprates. Here we have investigated the optical conductivity of t