We present a method for intrusion detection which is based on the Mach-Zehnder interference effect. This device provides monitored surveillance by continuously measuring the intensity of light collected by a pair of photodetectors. We find that our protocol allows for the detection of intrusion attempts which employ path- redirection and/or intercept-resend techniques. Expectation values for the registered output flux are provided for normal and interrupted operation.
@article{arxiv.1303.6701,
title = {Quantum-Secured Surveillance Based on Mach-Zehnder Interferometry},
author = {C. Allen Bishop and Travis S. Humble and Ryan S. Bennink and Brian P. Williams},
journal= {arXiv preprint arXiv:1303.6701},
year = {2013}
}