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arXiv · 2406.08028

Effective Polaron Dynamics of an Impurity Particle Interacting with a Fermi Gas

Duc Viet Hoang·Peter Pickl
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Abstract

We study the quantum dynamics of a homogeneous ideal Fermi gas coupled to an impurity particle on a three-dimensional box with periodic boundary condition. For large Fermi momentum $k_\text{F}$, we prove that the effective dynamics is generated by a Fr\"ohlich-type polaron Hamiltonian, which linearly couples the impurity particle to an almost-bosonic excitation field. Moreover, we prove that the effective dynamics can be approximated by an explicit coupled coherent state. Our method is applicable to a range of interaction couplings, in particular including interaction couplings of order 1 and time scales of the order $k_\text{F}^{-1}$.

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Duc Viet Hoang, Peter Pickl. 2024-06-12. Effective Polaron Dynamics of an Impurity Particle Interacting with a Fermi Gas. https://doi.org/10.1007/s00023-024-01532-0

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