1. University of Tokyo,Research Center for Advanced Science and Technology,Tokyo,Japan,153-0041
2. Graduate Institute of Photonics and Optoelectronics, National Taiwan University,Department of Electrical Engineering,Taipei,Taiwan R.O.C.,10617
3. Corning Incorporated,Corning,New York,USA,14831
4. National Yang-Ming Chiao-Tung University,Department of Photonics,Hsinchu,Taiwan R.O.C.,30050