2015年1月5日（周一）上午9:30，量子物質科學協同創新中心 & 物理系seminar：

報告題目： 2-dimensional Superconductivity at the LaAlO3/SrTiO3 Interface 報告人：李丹楓 DQMP, University of Geneva 報告時間： 2015.1.5 9:30 am 報告地點：清華理科樓三樓報告廳摘要： The interface between LaAlO3 and SrTiO3, two good band insulators, which was found in 2004 to be conducting [1], and, in some doping range, superconducting with a maximum critical temperature of about 200 mK [2] is attracting of lot of attention. The electron gas has a thickness of a few nanometers at low temperatures and a low electronic density, typically 5 1013 electrons/cm2. Being naturally sandwiched between two insulators, it is ideal for performing electric field effect experiments that allow the carrier density to be tuned.
I will discuss in this presentation superconductivity, the phase diagram of the system and the link with doped bulk SrTiO3 [2,3]; spin orbit and recent experiments on nanostructures that reveal a remarkable tuning of the electronic properties and allow weak localization and weak anti-localization as a function of doping and temperature to be followed [4,5]. Finally, I will discuss an approach [6] that should allow superconducting coupling between different gases in the functional bi-interface LaAlO3/SrTiO3 heterostructures to be studied.
[1] A. Ohtomo, H. Y. Hwang, Nature 427, 423 (2004).
[2] N. Reyren, S. Thiel, A. D. Caviglia, L. Fitting Kourkoutis, G. Hammerl, C. Richter, C. W. Schneider, T. Kopp, A.-S. Ruetschi, D. Jaccard, M. Gabay, D. A. Muller, J.-M. Triscone and J. Mannhart, Science 317, 1196 (2007).
[3] A. D. Caviglia, S. Gariglio, N. Reyren, D. Jaccard, T. Schneider, M. Gabay, S. Thiel, G. Hammerl, J. Mannhart, and J.-M. Triscone, Nature 456, 624 (2008).
[4] A. D. Caviglia, M. Gabay, S. Gariglio, N. Reyren, C. Cancellieri, and J.-M. Triscone, Physical Review Letters 104, 126803 (2010).
[5] A. Fête, S. Gariglio, A. D. Caviglia, M. Gabay, and J.-M. Triscone, Physical Review B (RC) 86, 201105 (2012).
[6] D. Li, S. Gariglio, C. Cancellieri, A. Fête, D. Stornaiuolo, and J.-M. Triscone, APL Materials 2, 012102 (2014). 報告人簡介：李丹楓，男，1986年8月生。目前于日内瓦大學攻讀博士學位（四年級），導師為鈣钛礦氧化物界面與異質結領域著名學者Jean-Marc Triscone教授。2008年畢業于浙江大學材料科學與工程系，之後就讀于香港理工大學應用物理系，并于2011年獲得理學碩士學位。期間，于2010年2月至8月，在日内瓦大學做短期訪問，并完成碩士論文。碩士以來的研究方向和研究興趣主要為：鈣钛礦過渡金屬元素氧化物異質結的外延生長和超晶格結構的制備、氧化物界面輸運性質與場效應調制、低維系統超導态等。博士的研究課題為“鈣钛礦型過渡金屬氧化物界面二維電子态的電子輸運及超導特性”。過去的三年中，作為第一作者或共同作者，共發表或投稿論文7篇，共參加國際性學術會議19次，并在重要國際會議上做報告9次，其中包括在美國材料研究學會春季年會上做邀請報告一次。