1. 1Bell Labs, Alcatel-Lucent, 791 Holmdel Road, Holmdel, NJ 07733, USA
2. 2Bell Labs, Alcatel-Lucent, 600 Mountain Avenue, Murray Hill, NJ 07974, USA
3. 3III-V Lab, a joint lab of ‘Alcatel-Lucent Bell Labs France’, ‘Thales Research and Technology’ and ‘CEA Leti’, Campus Polytechnique, 1, Avenue A. Fresnel, 91767 Palaiseau cedex, France