1. Aston Institute of Photonic Technologies, School of Engineering and Applied Science, Aston University, Birmingham B4 7ET, United Kingdom
2. Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, 9 avenue Alain Savary, BP 47870, Dijon Cedex 21078, France
3. OFS Fitel, Somerset, New-Jersey, USA