Toward “quantum supremacy” with single photons

主讲人 (Speaker): 

陆朝阳

主讲人单位 (Speaker's Institute): 

中国科学技术大学

邀请人 (Invited by): 

李朝红

时间 (Time): 

星期五, 2019/01/04 - 16:45 to 18:00

地点 (Location): 

珠海校区海滨红楼17栋107 (Rm 107, Red House 17)

摘要 (Abstract): 

       Quantum computers can in principle solve certain problems faster than classical computers. Despite substantial progress in the past decades, building quantum machines that can actually outperform classical computers for some specific tasks—a milestone termed as “quantum supremacy”—remained challenging. Boson sampling has been considered as a strong candidate to demonstrate the “quantum supremacy”.The experimental challenge for realizing a large-scale boson sampling mainly lies in the lack of a perfect single-photon sources. In this talk, I will report two routes towards building boson sampling machines with many photons, which is also a first, necessary toward photonic quantum computing. In the first path, we developed SPDC two-photon source with simultaneously a collection efficiency of 97% and an indistinguishability of 96% between independent photons. With this, we demonstrate genuine entanglement of 12 photons.In the second path, using a quantum dot-micropillar, we produced single photons with high purity (>99%), near-unity indistinguishability for >1000 photons, and high extraction efficiency—all combined in a single device compatibly and simultaneously. We build 3-, 4-, and 5-bosonsampling machines which runs >24,000 times faster than all the previous experiments, and for the first time reaches a complexity about 100 times faster than the first electronic computer (ENIAC) and transistorized computer (TRADIC).  We hope to achieve 20-photon boson sampling in the near term. Relevant papers can be found at http://staff.ustc.edu.cn/~cylu.

主讲人简介 (Speaker's CV): 

陆朝阳，剑桥大学物理学博士，中国科学技术大学教授，长期致力于量子光学和量子信息的研究，在包括《现代物理评论》1篇、《自然》和《科学》5篇、《自然》子刊9篇、《美国科学院院刊》4篇、《物理评论快报》29篇等国际顶级学术期刊发表论文70余篇，被引用6700余次。作为第一或通讯作者的研究成果一次入选Physics World评选的Breakthrough of the year (2015)，两次(2016、17)入选美国光学学会OPN评选的国际光学重要进展，四次(2007、12、15、17)入选两院院士评选的年度中国科技十大进展新闻。先后入选中组部国家青年千人计划(2011)、美国光学学会会士(2016)、《自然》“Science star of China”(2016)，获得香港求是科技基金会杰出青年学者奖(2014)、国家杰出青年科学基金(2015)、国家自然科学一等奖(2015)、中国五四青年奖章(2017)、欧洲物理学会菲涅尔奖(2017)。