On the Experimental Estimation of Surface Enhanced Raman Scattering (SERS) Cross Sections by Vibrational Pumping

A conclusive demonstration of vibrational pumping and determination of SERS cross sections

We provide conclusive demonstration of vibrational pumping under Surface Enhanced Raman Scattering (SERS) conditions by performing anti-Stokes/Stokes ratio measurements down to 10 K using dried silver colloids, the dye rhodamine 6G and 676 nm laser excitation. The method we propose allows the measurement of the SERS cross sections for different modes and the determination of the asymmetry between the anti-Stokes and Stokes SERS cross sections.

Temperature dependent anti-Stokes/Stokes ratios under Surface Enhanced Raman Scattering (SERS) conditions

We make systematic measurements of Raman anti-Stokes/Stokes (aS/S) ratios using two different laser excitations (514 and 633 nm) of rhodamine 6G (RH6G) on dried Ag colloids over a wide range of temperatures (100 to 350 K). We show that a temperature scan allows the separation of the contributions to the aS/S ratios from {\it resonance effects} and {\it heating/pumping}, thus decoupling the two main aspects of the problem. The temperature rise is found to be larger when employing the 633 nm laser. In addition, we find evidence for mode specific vibrational pumping at higher laser power densitie…

通过泵浦和探针表面增强振动光谱研究单分子内分子振动再分布

Addressing intramolecular vibrational redistribution in a single molecule through pump and probe surface-enhanced vibrational spectroscopy

本文通过泵浦和探针表面增强振动光谱研究单分子内分子振动再分布，利用量子力学框架分析振动光谱优化IVR表征的策略。

Energy-efficient pathway for selectively exciting solute molecules to high vibrational states via solvent vibration-polariton pumping

Selectively exciting target molecules to high vibrational states is inefficient in the liquid phase, which restricts the use of IR pumping to catalyze ground-state chemical reactions. Here, we demonstrate that this inefficiency can sometimes be solved by confining the liquid to an optical cavity under vibrational strong coupling conditions. For a liquid solution of 13CO2 solute in a 12CO2 solvent, cavity molecular dynamics simulations show that exciting a polariton (hybrid light-matter state) of the solvent with an intense laser pulse, under suitable resonant conditions, may lead to a very str…

Triplet-singlet conversion by broadband optical pumping

We demonstrate the conversion of cold Cs_{2} molecules initially distributed over several vibrational levels of the lowest triplet state a^{3}Σ_{u}^{+} into the singlet ground state X^{1}Σ_{g}^{+}. This conversion is realized by a broadband laser exciting the molecules to a well-chosen state from which they may decay to the singlet state throug\textcolor{black}{h two sequential single-photon emission steps: Th}e first photon populates levels with mixed triplet-singlet character, making possible a second spontaneous emission down to several vibrational levels of the X^{1}Σ_{g}^{+} states. By ad…

选定镧系-柠檬酸配合物的表面增强拉曼散射与密度泛函理论研究（镧系元素：La、Ce、Pr、Nd、Sm、Eu和Gd）

Surface-enhanced Raman scattering and density functional theory study of selected-lanthanide-citrate complexes (lanthanide: La, Ce, Pr, Nd, Sm, Eu, and Gd)

本研究结合SERS与DFT计算，研究七种镧系-柠檬酸配合物在不同波长激发下的SERS光谱，完成峰归属并揭示强度比规律及镧系离子4f电子对配位结构的影响。