Origin of Quantum Beats in 2D Electronic Spectroscopy: Electronic versus Vibrational Coherences

• Main Authors: Hung-Hsuan Lin, 林紘玄
• Other Authors: Yuan-Chung Cheng
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/74276141298363351262

碩士 === 國立臺灣大學 === 化學研究所 === 101 === Over billions of years, photosynthetic organisms have developed sophistic light-harvesting systems. These systems can efficiently capture solar energy and then transmit the energy to reaction centre with high quantum yield. We can learn about the mechanism of en- ergy transfer through two-dimensional (2D) electronic spectroscopy. So far, it is believed that the efficient energy transfer is related to quantum coherence. In this work, We study the coherence quantum beats in 2D electronic spectroscopy calculated by a theoretical method based on a time-nonlocal quantum master equation and a scheme for the evalua- tion of the third-order photon echo polarization. We aim to examine how electronic and vibrational coherence can be distinguished in 2D spectra. We do find unique characteris- tics of vibrational coherence that help us distinguish electronic and vibrational coherence. In this work we find that two-dimensional electronic spectroscopy provide more informa- tion and more understand the mechanism of energy transfer in photosynthetic organisms.