一周讲座信息（11.14-11.20）本周内（11.14-11.20）本校和部分高校

一周物理讲座

北京大学

报告题目：

Connected and disconnected contributions to pion-pion scattering

报告人：Prof. 郭奉坤

地点：物理楼南408

时间：11月16日（周四）15:00

报告摘要：

We show that the interplay of chiral effective field theory and lattice QCD can be used in the evaluation of so-called disconnected diagrams, which appear in the study of the isoscalar and isovector channels of pion-pion scattering and have long been a major challenge for the lattice community. By means of partially-quenched chiral perturbation theory, we distinguish and analyze the effects from different types of contraction diagrams to the pion-pion scattering amplitude, including its scattering lengths and the energy-dependence of its imaginary part. Our results may be used to test the current degree of accuracy of lattice calculation in the handling of disconnected diagrams, as well as to set criteria for the future improvement of relevant lattice computational techniques that may play a critical role in the study of other interesting QCD matrix elements.

报告题目：

太赫兹波前获取与调控

报告人：张岩教授

地点：物理楼中211

时间：11月15日（周三） 15:10-18:00

报告摘要：

本报告介绍首都师范大学超材料与器件北京市重点实验室在太赫兹波前获取和调控方面取得的进展。利用自主研发的太赫兹脉冲波焦平面成像系统实现太赫兹辐射的频率、振幅、相位以及偏振态的测量，并利用这套系统实现对涡旋光束和太赫兹波段表面等离子体器件的的表征。利用超表面技术实现太赫兹波前的调控，设计了超薄太赫兹平板透镜，长焦深透镜，多焦点透镜、太赫兹全息、分色成像全息以及偏振选择透镜等器件。利用半导体材料在太赫兹波段特殊的光电调控特性，提出了太赫兹波前调制器，实现了太赫兹波前的动态调控。

报告题目：

Fiber based nonlinear quantum optical devices

报告人：李小英教授

地点：物理楼中215

时间：11月16日（周四）14:30

报告摘要：

Quantum information science and technology has made a great achievement in the past decades, however, many quantum devices, often suffer from the drawbacks of large dimension, high cost, and the difficulties in operation and maintenance, which imped its practical application. Using the third order nonlinearity in optical fiber, we investigate the realization of the quantum optical devices which are low cost, compact, and ease in operation and mantenance. In this talk, we first present the work on generating the quantum light sources in both discrete variable and contunuous variable states. We then demonstrate the applications of our quantum light sources in quantum metrology and quantum information processing.

报告题目：

Early Results of the Subaru Hyper Suprime-Cam Survey for High Redshift Galaxies

报告人：Masami Ouchi

时间：11月16日（周四）16:00-17:00

地点：KIAA-PKU Auditorium

报告摘要：

I present progresses of our Subaru Hyper Suprime-Cam (HSC) optical imaging

survey for high redshift galaxies including Lyman alpha emitters (LAEs),and overview the early results. The data of the early results allow us to obtain over a half million galaxies at z~4-7 in a total area of>100 deg^2 that are about 1-2 orders of magnitude larger than those of previous high-z galaxy surveys. With the large Subaru/HSC galaxy sample supported by the spectra taken with Keck, Subaru, and Magellan,and the large-area deep Spitzer data, I will present various statistical

measurements including luminosity functions and correlation functions,and discuss galaxy formation and cosmic re-ionization based on our ten papers for refereed journals, seven of which are already accepted for publication.

报告题目：

Opportunities and Challenges of Wind Power in China

报告人：鲁玺副教授

时间：11月15日（周三）15:00

地点：物理楼北547

报告摘要：

Expanding renewable capacity, especially wind power, is a central strategy to achieve China’s climate goals. Despite greater capacity for wind installation in China compared to the US, less wind electricity is generated in China. The talk will focus on tackling such a complicated issue. It will begin with a brief review on the policy and history for development of wind power in China and then address particularly its economically feasible potential of wind power. In this context, a new approach is proposed to quantify the relative importance of the key factors accounting for the unsatisfactory performance of Chinese wind farms.

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