1. School of Materials Science and Engineering Georgia Institute of Technology Atlanta Georgia 30332 United States
2. School of Materials Science and Engineering Jingdezhen Ceramic Institute Jingdezhen Jiangxi 333403 P. R. China
3. Department of Physics Arizona State University Tempe Arizona 85287 United States
4. Department of Chemistry Agnes Scott College 141 E College Avenue Decatur Georgia 30030 United States