We propose a novel interferometer by using optical transverse modes in multimode waveguide that can beat the standard quantum limit. In the scheme, the classical simulation of N-partical quantum entangled states is generated by using N independent classical fields and linear optical elements. Similar to the quantum-enhanced measurements, the classical simulation can also achieve N enhancement over the precision of the measurement N times for independent fields. Due to only using classical fields and linear optical elements, the scheme can be realized much more easily.
@article{arxiv.quant-ph/0604103,
title = {A novel interferometer to beat the standard quantum limit using optical transverse modes in multimode waveguide},
author = {Jian Fu},
journal= {arXiv preprint arXiv:quant-ph/0604103},
year = {2007}
}