A multiple round quantum dense coding (MRQDC) scheme based on the quantum phase estimation algorithm is proposed. Using an m+1 qubit system, Bob can transmit 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m+1 bits. We have implemented the scheme in a three- qubit nuclear magnetic resonance (NMR) quantum computer. The experimental results show a good agreement between theory and experiment.
@article{arxiv.quant-ph/0407104,
title = {Multiple Round Quantum Dense Coding And Its Implementation Using Nuclear Magnetic Resonance},
author = {Jingfu Zhang and Jingyi Xie and Chuan Wang and Zhiwei Deng and Zhiheng Lu and Guilu Long},
journal= {arXiv preprint arXiv:quant-ph/0407104},
year = {2007}
}