講演情報
[10a-PA1-9]Mode Number Dependent Free Energy Landscape Reorganization and Photophysical Dynamics Under Electronic Strong Coupling.
〇(D)Nafees Umar Draz1, Soh Kushida1, Yohei Yamamoto1,2,3 (1.Institute of Pure and Applied Sciences, University of Tsukuba, 2.Tsukuba Research Center for Energy Materials Science (TREMS), University of Tsukuba, 3.Hydrogen Boride Research Center (HBRC), Tsukuba Institute for Advanced Research (TIAR))
キーワード：
Light-matter interaction、Strong coupling、ultra-fast spectroscopy
When the energy exchange rate between a light and molecular excitation exceeds dissipation rates it gives rise to the hybrid states such as upper (UP) and lower polaritons (LP) and system is said to be under strong coupling (SC). In the SC regime, polaritonic states modulate photophysical processes, while exact mechanisms remain elusive. A primary factor is the reordering of the energy landscape with respect to cavity mode number (m) even with constant Rabi splitting. We fabricated four Fabry-Perot microcavities with a constant Rabi splitting of 0.46±0.02 eV (m=1,2,4,5) using a rhodamine-B doped PVP matrix. Under SC, LP emission broadened with higher mode numbers, revealing a doublet-like feature for m=4,5. Ultrafast transient absorption spectroscopy showed that the slow decay constant (τ2) increased from ∼1 ns for lower modes to ∼2 ns for m=4,5 coinciding with a long-lived trapped state induced by the increased dark-state density of states.