1. Instituto de Investigación en Comunicación Óptica, Universidad Autónoma de San Luis Potosí, 78220 San Luis Potosí, Mexico
2. Institute of Physics, Humboldt University of Berlin, 12489 Berlin, Germany
3. Research Institute for Supercomputing, Nizhny Novgorod State University, Nizhny Novgorod, Russia
4. BioCircuits Institute, University of California, San Diego, La Jolla, California 92093-0328, USA