[1] Shanghai Jiao Tong Univ, Tsung Dao Lee Inst, Shanghai 200240, Peoples R China
[2] Renmin Univ China, Dept Phys, Beijing 100872, Peoples R China
[3] Renmin Univ China, Beijing Key Lab Optoelect Funct Mat & Micronano D, Beijing 100872, Peoples R China
[4] Natl Inst Stand & Technol, NIST Ctr Neutron Res, Gaithersburg, MD 20899 USA
[5] Osaka Univ, Grad Sch Sci, Ctr Adv High Magnet Field Sci, Toyonaka, Osaka 5600043, Japan
[6] Oak Ridge Natl Lab, Neutron Scattering Div, Oak Ridge, TN 37831 USA
[7] Chinese Acad Sci, Beijing Natl Lab Condensed Matter Phys, Inst Phys, Beijing 100190, Peoples R China
[8] Sez Trieste, INFN, Via Bonomea 265, I-34136 Trieste, Italy
[9] Sez Trieste, SISSA, Via Bonomea 265, I-34136 Trieste, Italy
[10] Budapest Univ Technol & Econ, Inst Phys, BME MTA Stat Field Theory Res Grp, Budafoki Ut 8, H-1111 Budapest, Hungary
[11] Budapest Univ Technol & Econ, Dept Theoret Phys, MTA BME Quantum Dynam & Correlat Res Grp, Budafoki Ut 8, H-1111 Budapest, Hungary
[12] Chinese Acad Sci, Fujian Inst Res Struct Matter, State Key Lab Struct Chem, Fuzhou 350002, Fujian, Peoples R China
[13] Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan
[14] Shanghai Jiao Tong Univ, Sch Phys & Astron, Key Lab Artificial Struct & Quantum Control, Shenyang Natl Lab Mat Sci,Minist Educ, Shanghai 200240, Peoples R China
[15] Shanghai Jiao Tong Univ, Sch Phys & Astron, Shanghai 200240, Peoples R China