[1] Rutgers State Univ, Ctr Mat Theory, Piscataway, NJ 08854 USA
[2] Univ Maryland, NIST, Joint Quantum Inst, College Pk, MD 20742 USA
[3] Univ Maryland, NIST, Joint Ctr Quantum Informat & Comp Sci, College Pk, MD 20742 USA
[4] South China Normal Univ, Sch Phys & Telecommun Engn, Guangzhou 510006, Guangdong, Peoples R China
[5] Univ Cape Town, Dept Math & Appl Math, Lab Quantum Grav & Strings, Private Bag, ZA-7700 Rondebosch, South Africa
[6] Natl Taiwan Univ, Dept Phys, Taipei 10617, Taiwan
[7] Natl Taiwan Univ, Ctr Theoret Sci, Taipei 10617, Taiwan