We introduce the concept of directional coupling, i.e., the selective transfer of a state between adjacent quantum wires, in the context of quantum computing and short-distance communication. Our analysis rests upon a mathematical analogy between a dual-channel directional coupler and a composite spin system.
@article{arxiv.0812.1281,
title = {Directional Coupling for Quantum Computing and Communication},
author = {Georgios M. Nikolopoulos},
journal= {arXiv preprint arXiv:0812.1281},
year = {2008}
}