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arXiv · 2206.00673

Shot noise in a strange metal

Liyang Chen·Dale T. Lowder·Emine Bakali·Aaron Maxwell Andrews·Werner Schrenk·Monika Waas·Robert Svagera·Gaku Eguchi·Lukas Prochaska·Yiming Wang·Chandan Setty·Shouvik Sur·Qimiao Si·Silke Paschen·Douglas Natelson
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Abstract

Strange-metal behavior has been observed in materials ranging from high-temperature superconductors to heavy fermion metals. In conventional metals, current is carried by quasiparticles; although it has been suggested that quasiparticles are absent in strange metals, direct experimental evidence is lacking. We measured shot noise to probe the granularity of the current-carrying excitations in nanowires of the heavy fermion strange metal YbRh2Si2. When compared with conventional metals, shot noise in these nanowires is strongly suppressed. This suppression cannot be attributed to either electron-phonon or electron-electron interactions in a Fermi liquid, which suggests that the current is not carried by well-defined quasiparticles in the strange-metal regime that we probed. Our work sets the stage for similar studies of other strange metals.

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Liyang Chen, Dale T. Lowder, Emine Bakali, Aaron Maxwell Andrews, Werner Schrenk, Monika Waas, Robert Svagera, Gaku Eguchi, Lukas Prochaska, Yiming Wang, Chandan Setty, Shouvik Sur, Qimiao Si, Silke Paschen, Douglas Natelson. 2022-06-01. Shot noise in a strange metal. https://doi.org/10.1126/science.abq6100

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