Quantum state engineering with ququarts: Application for deterministic QKD protocolA. P. Shurupov, S. S. Straupe, S. P. Kulik, M. Gharib and M. R. B. WahiddinEPL, 87 1 (2009) 10008DOI: https://doi.org/10.1209/0295-5075/87/10008