2019年第80回応用物理学会秋季学術講演会

講演情報

一般セッション(口頭講演)

4 JSAP-OSA Joint Symposia 2019 » 4.3 Ultrafast Optics and Laser Processing

[20p-E214-1~14] 4.3 Ultrafast Optics and Laser Processing

2019年9月20日(金) 13:15 〜 18:30 E214 (E214)

井手口 拓郎(東大)、Set Sze(東大)、山下 真司(東大)

18:00 〜 18:15

[20p-E214-13] Improvement and Quantitative Evaluation of Asynchronous Optical Sampling Method using Dual-comb towards Semiconductor Physics

〇(M2)Tomohito Saito1、Akifumi Asahara2,3、Kouichi Akahane4、Kaoru Minoshima2,3、Junko Ishi-Hayase1 (1.Keio Univ.、2.UEC、3.ERATO MINOSHIMA IOS、4.NICT)

キーワード:Dual comb, Asynchronous optical sampling, Pump-probe method

It is important to measure transient responses of excitons in quantum dots (QDs) from viewpoints of fundamental and applied researches. Ultrafast nonlinear spectroscopies such as pump-probe (PP) and photon echo (PE) techniques have been traditionally used to measure population and coherent dynamics of QDs. However, as traditional PP and PE techniques use mechanical stages to scan the time delay between excitation pulses, there have been problems such as a short measurable time range, long acquisition time, and low signal-to-noise (S/N) ratio.
In order to solve these problems, we develop asynchronous optical sampling (ASOPS) technique using dual-comb light sources. In this presentation, we experimentally demonstrate the dual-comb ASOPS PP measurement with wide temporal dynamic range, short acquisition time, and high S/N ratio, that is suitable to study excitonic population dynamics in QDs. The performance of the dual-comb ASOPS method is compared to that of conventional PP method using a mechanical stage. We show the usability of dual-comb ASOPS technique for studying dynamics of QDs.