2013年1月25⽇（星期五） 频标楼3楼报告厅 上午10：30－12:00 林海清教授，1981年毕业于 中科大物理系，1983年获爱 荷华州立大学硕士学位， 1987年获加州大学圣迭戈分 校博士学位。现任北京计算 科学中心主任，国家第二批 “千人计划”引进人才。研 究领域为凝聚态物理和计算 物理，已发表学术论文200余 篇。2003年获选为Fellow of American Physical Society。 林海青 教授 北京计算科学研究中心 武汉物数所理论与交叉学术交流系列报告（三十九） Theoretical Studies on Recent Discovered Organic Superconductors In this talk, I report our recent study on the magnetic and pair binding properties in newly discovered polycyclic aromatic hydrocarbon (PAH) superconductors including alkali-metal-doped picene, coronene, phenanthrene, and dibenzopentacene. To gain a better understanding on magnetism and electron correlation in PAH, we have performed a systematic numerical investigation on the correlation effects and model the Ï€ -electrons on the carbon atoms of a single molecule by a one-orbital Hubbard model, in which the energy difference Ïµ between carbon atoms with and without hydrogen bonds is taking into account. We demonstrate that the spin polarized ground state is realized for charged molecules in the physical parameter regions, which provides a reasonable explanation of local spins observed in PAHs. In alkali-metal-doped dibenzopentacene, our results show that electron correlation may produce an effective attraction between electrons for the charged molecule with one or three added electrons. We also propose a different doping pattern which may lead to higher transition temperature. Some results on the possible structure of PAH as functions of pressure and doing will be discussed.