Electron Jamming and the Unusual Charge Response of Strange Metals

Recent measurements [1] of the dynamical charge response of optimally doped cuprate “strange” metals have revealed a broad, featureless continuum of excitations, extending over much of the Brillouin zone. The nature of this continuum and the absence of a long-lived plasmon excitation is strikingly at odds with the expectations of Fermi liquid theory. In this work, we investigate the bosonic collective modes and the particle-hole excitations of strange metals by making an analogy to lattices falling apart across a “jamming” transition [2]. We reproduce many of the qualitative features of the measured density-density response of strange metals using the above framework and speculate on the possibility that strongly interacting electrons can undergo a jamming transition.

[1] M. Mitrano et al., PNAS 115 (21) 5392-5396 (2018)
[2] A. Liu and S. Nagel, Annual Review of Condensed Matter Physics Vol. 1:347-369 (2010)