The charge of the subgap states in an Andreev quantum dot (AQD; this is a quantum dot inserted into a superconducting loop) is very sensitive to the magnetic flux threading the loop. We study the sensitivity of this device as a function of its parameters for the limit of a large superconducting gap. In our analysis, we account for the effects of a weak Coulomb interaction within the dot. We discuss the suitability of this setup as a device detecting weak magnetic fields.
@article{arxiv.0706.2635,
title = {Magnetic flux detection with an Andreev Quantum Dot},
author = {I. A. Sadovskyy and G. B. Lesovik and G. Blatter},
journal= {arXiv preprint arXiv:0706.2635},
year = {2010}
}