| 2013 | Seminar Speaker | International Center for Quantum Physics, Peking University, Beijing, China, June 10, 2013. |
| 2013 | Invited Speaker | 14th International Workshop on ``Vortex Physics'', Nanjing, China, May 21-28, 2013. |
| 2013 | Invited Speaker | APS March Meeting, Baltimore, MD, March 20-24, 2013. |
| 2012 | Invited Speaker | International Workshop on ``Phase Separation and Superstripes'', Erice, Italy, July 11-17, 2012. |
| 2012 | Invited Speaker | PLASMA2012, Cesme, Turkey, June 10-13, 2012. |
| 2011 | Invited Speaker | Second JST-DFG Workshop on ``Terahertz superconductors Electronics'', Blaubeuren, Germany, October 16-19, 2011. |
| 2010 | Invited Speaker | First JST-DFG Workshop on ``Terahertz Superconductor Electronics'', Tsukuba, Japan, February 21-24, 2010. |
| 2010 | Invited Speaker | PLASMA2010, Hirosaki, Japan, April 30-May 2, 2010. |
| 2010 | Invited Speaker | International Workshop on ``Quantum Coherent Properties of Spins III'', UCF, December 20-22, 2010. |
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| 2009 | Invited Speaker | Coma-ruga V International Workshop on ``Nanomagnetism and Superconductivity", Coma-ruga, Spain, July 7-10, 2009. |
| 2009 | Invited Speaker | Symposium on ``Spin Physics and Nanomagnetism'', Lehman College, CUNY, March 13-14. |
| 2009 | Co-Chair, Plenary Invited Speaker, and Proceedings Editor | 7th International Conference on ``New Theories, Discoveries, and Applications of Superconductors and Related Materials,'' Beijing, China, May 13-16. |
| 2008 | Invited Speaker | Plasma2008, Pohang, Korea, July 17-19. |
| 2008 | Invited Speaker | MiniWorkshop on ``Terahertz Radiation from Superconductors'', Tokyo, Japan, November 20-21. |
| 2008 | Invited Speaker | 3rd Annual Autumn Lectures on ``Nanoscience and Engineering for Young Scientists'', Tokyo, Japan, November 22-28. |
| 2008 | Invited Speaker | Condensed Matter Theories, Loughborough, UK August 11-18. |
| 2007 | Invited Speaker | Coma-ruga III International Workshop on ``Nanomagnetism", Coma-ruga, Spain, July 1-4 |
| 2007 | Invited Speaker | International Workshop on ``The Road to Room Temperature Superconductivity'', Loen, Norway, June 17-23 |
| 2007 | Co-Chair, Plenary Invited Speaker, and Proceedings Editor | 6th Interantional Conference on ``New Theories, Discoveries, and Applications of Superconductors and Related Materials'', Sydney, Australia, Jan. 6-11 |
| 2006 | Invited Speaker | APS March Meeting, Baltimore, MD |
| 2004 | Invited Speaker | 4th International Conference on ``Nanoscale Heterogeneity and Quantum Phenomena in Complex Oxides (Stripes 2004)'', Rome, Italy, Sept. 26-Oct. 2 |
| 2004 | Plenary Invited Speaker | 5th International Conference on ``New Theories, Discoveries, and Applications of Superconductors and Related Materials'', Chongqing, China, June 10-15 |
| 2004 | Invited Speaker | 2004 University of Miami Conference on ``High Temperature Superconductvity'', Miami, FL Jan. 11-16 |
| 2003 | Invited Speaker | International Workshop on ``Quantum Transport in Synthetic Metals & Quantum Functional Semiconductors, 2003'', Seoul, Korea, Nov. 19-22 |
| 2003 | Invited Speaker | International Conference on ``Dynamic Inhomogeneities in Complex Oxides'', Bled, Slovenia, June 14-20 |
| 2003 | Invited Speaker | STS 2003 Conference on ``Nonequilibrium Physics at Short Times Scales'', Dresden, Germany, May 5-16 |
2002| Invited Speaker | 23rd International Conference on Low Temperature Physics (LT23), Hiroshima, Japan, Aug. 20-27 | |
| 2002 | Invited Speaker | STS 2002 Conference on ``Formation of Correlations'', Bad Honnef, Germany, June 24-28 |
| 2002 | Invited Speaker | SCRM 2002 Meeting on ``Superconductivity, CMR and Related Materials'', Giens, France June 1-8 |
| 2002 | Invited Speaker | University of Tennessee-Knoxville Workshop on Chemical Physics, Knoxville, TN Feb. 7-8 |
| 2001 | Invited Speaker | NATO Advanced Research Workshop on ``New Trends in Superconductivity'', Yalta, Ukraine, Sept. 16-20 |
| 2001 | Invited Speaker | APS March Meeting, Seattle, WA
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| 2001 | Co-Chairman | Third International Conference on ``New Theories, Discoveries, and Applications of Superconductors and Related Materials'', Jan. 16-19, Honolulu, HW |
| 2000 | Invited Speaker | 48th Midwest Solid State Physics Symposium, University of North Dakota, Grand Forks, ND, Oct. 14-15 |
| 2000 | Invited Lecturer | 25th International Nathiagali Summer College, Nathiagali, Pakistan, June 26-July 15 |
| 2000 | Opponent | Ph. D. Thesis Defense of Dr. Johan Axnäx, Kungliga Tekniska Högskolan, Stockholm, Sweden, March 10 |
| 2000 | Invited Speaker | Gordon Conference on ``Superconductivity'', Harbortown Resort, Ventura, CA |
| 1999 | Invited Speaker | Second International Conference on ``New Theories, Discoveries, and Applications of Superconductors and Related Materials'', Las Vegas, NV |
| 1998 | Invited Speaker | SPIE Conference 3480 on ``Superconducting Superlattices II: Native and Artificial'', San Diego, CA |
| 1998 | Plenary Invited Speaker | NATO Advanced Research Workshop on ``Symmetry and Pairing in Superconductivity'', Yalta, Crimea, Ukraine |
| 1998 | Plenary Invited Speaker | First International Conference on ``New Theories, Discoveries, and Applications of Superconductors and Related Materials'', Baton Rouge, LA |
| 1997 | Chairman | 25th Midwest Solid state Theory Symposium, Argonne National Laboratory, Argonne, IL |
| 1997 | Invited Lecturer | Institut für Theoretische Festkörperphysik, Universität Hamburg, Hamburg, Germany, July 4-11. |
| 1997 | Invited Lecturer | Department of Industrial Chemistry, Tokyo Unaiversity, Tokyo, Japan, April 7-18. |
| 1996 | Plenary Invited Speaker | International Workshop on ``High Temperature Superconductivity-Ten Years After Its Discovery'', Jaipur, India |
| 1996 | Plenary Invited Speaker | Adriatico Research Conference on ``Fluctuation Phenomena in High Temperature Superconductors'', ICTP Trieste, Italy |
| 1996 | Invited Speaker | SPIE Conference on ``Oxide Superconductors: Physics and Nanoengineering II'', San Jose, CA |
| 1995 | Invited Speaker | 23rd Midwest Solid State Theory Conference, Kansas State University, Manhattan, KS |
| 1995 | Invited Speaker | 1995 Taiwan International Conference on ``Superconductivity'', Hualien, Taiwan, ROC |
| 1995 | Chairman | Workshop on ``Magnetism in Multilayered and Reduced Dimensional Systems'', Argonne National Laboratory, Argonne, IL |
| 1995 | Invited Speaker | APS March Meeting, San Jose, CA |
| 1994 | Invited Speaker | SPIE Technical Conference on ``Superconducting Superlattices and Multilayers'', Los Angeles, CA |
| 1993 | Chairman | Workshop on ``Electronic Properties of Disordered Systems'', Argonne National Laboratory, Argonne, IL |
| 1993 | Invited Speaker | AMS-SIAM-IMS Summer Research Conference on ``Mathematics of Superconductivity'', University of Washington, Seattle, WA |
| 1992 | Invited Speaker | Sixth Annual Conference on ``Superconductivity'', Buffalo, NY |
| 1992 | Invited Speaker | APS March Meeting, Indianapolis, IN |
| 1991 | Invited Speaker | Univ. Miami Workshop on ``Electronic Structure and Mechanisms for High Temperature Superconductivity'', Miami, FL |
| 1989 | Invited Speaker | Gordon Conference on ``Phenomenology of High Temperature Superconductors'', Wolfeboro, NH |
| 1989 | Invited Speaker | APS March Meeting, St. Louis, MO |
| 1988 | Invited Speaker | Conference on ``Phenomenology of High Temperature Superconductivity'', Los Alamos, NM |
| 1987 | Invited Speaker | 3rd International Workshop on ``Condensed Matter Theories'', Oulu, Finland |
| 1986 | Invited Speaker | XV Yamada Conference on ``Charge-density Waves'', Lake Kawaguchi, Japan |
| 1986 | Invited Speaker | 17th Rare Earth Conference, Hamilton, ON, Canada |
| 1986 | Invited Speaker | APS March Meeting, Las Vegas, NV |
| 1985 | Invited Speaker | International Conference on ``Charge Density Waves in Solids'', Budapest, Hungary |
| 1984 | Invited Speaker | Gordon Conference on ``Quantum Solids and Fluids'', Wolfeboro, NH |
| 1979 | Chairman | 27th Midwest Solid State Physics Conference, Ames, IA |
| 1977 | Participant | Joint US-USSR Symposium on Condensed Matter Physics, Aspen, CO |
| 1976 | Invited Speaker | 4th Midwest Solid State Theory Symposium, University of Chicago, Chicago, IL |