Fluctuation-Induced Quantum Friction of a Brownian Particle in the Anderson Model with Coulomb Interaction

by Aleksei Aleshin (Moscow State University)

Thursday 23 Apr 2026, 11:00 → 12:00 Europe/Zurich

Teams

Fluctuation-induced quantum friction, previously studied for water in nanotubes [1-2], is relevant for any quantum dot in an environment. In this talk, I discuss quantum Brownian motion of an impurity under a 2D electron gas within the Newns-Anderson model with Coulomb interaction. A mean-field approach for a non-equilibrium hybrid system with mechanical and field variables is developed, enabling self-consistent analysis of quantum corrections to the Langevin dynamics of the impurity's center of mass and their backaction on the friction coefficient. Within this model, the known friction coefficient due to Coulomb screening [1] is reproduced in first-order perturbation theory. Analysis of charge fluctuations from hopping versus Coulomb shows that zero-order hopping correlations are nonzero and can exceed first-order Coulomb fluctuations. The approach also yields the pure hopping friction force, which has the interesting feature of vanishing in the absence of other forces — a result whose explanation is discussed. The developed calculation technique can further be employed to analyze the stochastic behavior of particles in detectors during continuous quantum measurement.

[1] Kavokine, N., Bocquet, ML. & Bocquet, L. Fluctuation-induced quantum friction in nanoscale water flows. Nature 602, 84–90 (2022). https://doi.org/10.1038/s41586-021-04284-7.

[2] Coquinot, B., Bui, A.T., Toquer, D. et al. Momentum tunnelling between nanoscale liquid flows. Nat. Nanotechnol. 20, 397–403 (2025). https://doi.org/10.1038/s41565-024-01842-8