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arXiv:2512.01263

Inductive van der Waals Force between Two Quantum Loops

Kicheon Kang

cond-mat.mes-hallphysics.atom-phquant-phSubmitted Dec 1, 2025• Announced Dec 2, 2025• 0 citations
v1 · Dec 1, 2025v2 · Dec 10, 2025v3 · Dec 15, 2025v4 · Jul 28, 2026
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Abstract

We study the van der Waals-London force, which is typically associated with fluctuating dipoles in atoms, in a mesoscopic circuit consisting of two inductively coupled superconducting loops. We investigate the ``inductive" van der Waals-London interaction using both semiclassical and quantum electrodynamic (QED) approaches. The semiclassical model predicts a repulsive interaction due to anticorrelated current fluctuations. In contrast, the QED framework, which incorporates virtual photon exchange, reveals a predominantly attractive force. A key contribution comes from a state-independent two-photon exchange, which is absent in the semiclassical description and undetectable by spectroscopy. Our study introduces a new experimental platform for measuring the van der Waals force between individual artificial atoms via controlled mesoscopic circuits.

Comments
5 pages, 4 figures

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We study the van der Waals-London force, which is typically associated with fluctuating dipoles in atoms, in a mesoscopic circuit consisting of two inductively coupled superconducting loops. We investigate the ``inductive" van der Waals-London interaction using both semiclassical and quantum electrodynamic (QED) approaches. The semiclassical model predicts a repulsive interaction due to anticorrelated current fluctuations. In contrast, the QED framework, which incorporates virtual photon exchange, reveals a predominantly attractive force. A key contribution comes from a state-independent two-photon exchange, which is absent in the semiclassical description and undetectable by spectroscopy. Our study introduces a new experimental platform for measuring the van der Waals force between individual artificial atoms via controlled mesoscopic circuits.
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