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Pierre, F.

Publications and source records attributed to Pierre, F..

Probing single electron scattering through a non-Fermi-liquid charge-Kondo device

Among the exotic and yet unobserved features of multichannel Kondo impurity models is their subunitary single electron scattering. In the two-channel Kondo model, for example, an incoming electron is fully scattered into a many-body excitation such that the single particle Green's function vanishes. Here, we propose to directly observe these features in a charge-Kondo device encapsulated in a Mach-Zehnder interferometer, within a device already studied by Duprez et al. [Science 366, 1243 (2019)]. Finally, we provide detailed predictions for the visibility and phase of the Aharonov-Bohm oscillations depending on the number of coupled channels and the asymmetry of their couplings.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Emission of Whistler-mode waves and diffusion of electrons around interplanetary shocks

Whistler-mode wave emissions are frequently observed at and downstream of interplanetary shocks. Using electron distribution functions measured onboard Ulysses in the energy range 1.6 to 862 eV, we calculate the temperature anisotropy and the wave growth rate of the electromagnetic electron cyclotron instability, Results of the calculations are compared to the whistler wave spectra observed simultaneously. For the studied events there is a good correlation between the wave growth rates and the wave spectra. Particularly, upstream of the shock front where no wave emissions are observed, the anisotropy lies below the wave instability threshold, i.e. the critical anisotropy Ac; on the contrary, downstream of the shock, the anisotropy exceeds Ac in some frequency range. Moreover. the tact that the anisotropy is close to Ac in a large frequency range gives prominence to the effect of velocity space diffusion of the electrons by the waves.

Pierre, F.↗