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Updated: Aug 6, 2026

Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source
Published on: April 4, 2017
Signatures of a noise-induced quantum phase transition in a mesoscopic metal ring
Ning-Hua Tong1, Matthias Vojta
1Institut für Theorie der Kondensierten Materie, Universität Karlsruhe, 76128 Karlsruhe, Germany.
Abstract:
We study a mesoscopic ring with an inline quantum dot threaded by an Aharonov-Bohm flux. Zero-point fluctuations of the electromagnetic environment capacitively coupled to the ring, with omega(s) spectral density, can suppress tunneling through the dot, resulting in a quantum phase transition from an unpolarized to a polarized phase. We show that robust signatures of such a transition can be found in the response of the persistent current in the ring to the external flux as well as to the bias between the dot and the arm. Particular attention is paid to the experimentally relevant cases of Ohmic (s = 1) and sub-Ohmic (s = 1/2) noise.
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