[1]Joint Center for Quantum Information and Computer Science, University of Maryland, College Park 20740, USA;
[2]Institute for Advanced Study, Tsinghua University, Beijing 100084, China;
[3]Centre for Quantum Computation & Intelligent Systems, School of Software, Faculty of Engineering and Information Technology, University of Technology Sydney, Sydney 2007, Australia;
[4]State Key Laboratory of Computer Science.Institute ojSo'f~are, Chinese Academy of Sciences, Beijing 100084, China;
[5]Department of Mathematics, Iowa State University, Ames 50011-2140, USA;
[6]Institute for Quantum Computing, University of Waterloo, Waterloo N2L 3G1, Canada;
[7]Department of Mathematics & Statistics, University of Guelph, Guelph N1G 2 W1, Canada;
[8]Perimeter Institute for Theoretical Physics, Waterloo N2L 2Y5, Canada;