1. DTU Electro Department of Electrical and Photonics Engineering Technical University of Denmark Kgs. Lyngby 2800 Denmark
2. NORBLIS APS Virumgade 35D Virum 2830 Denmark
3. School of Electrical and Electronic Engineering The Photonics Institute Nanyang Technological University Singapore 639798 Singapore
4. School of Engineering University of Glasgow G12 8LT Glasgow UK
5. NKT Photonics A/S Blokken 84 Birkerød 3460 Denmark