1. Department of Physics, University of Rome “Tor Vergata” and INFN, Via della Ricerca Scientifica 1, 00133 Rome RM, Italy
2. Angewandte Mathematik und Numerische Analysis, Bergische Universität Wuppertal, Gaußstrasse 20, D-42119 Wuppertal, Germany
3. Computation-based Science and Technology Research Center, The Cyprus Institute, 20 Kavafi Str., Nicosia 2121, Cyprus
4. Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
5. Departmento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires 1428, Argentina