Center for Nonlinear Studies, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States.
J Phys Chem B. 2011 May 12;115(18):5372-82. doi: 10.1021/jp109453y. Epub 2011 Mar 10.
Employing the interband exciton scattering model, we have derived a closed set of equations determining the 2D double-quantum coherence signal sensitive to the interband Coulomb interactions (i.e., many-body Coulomb interactions leading to the couplings between exciton and biexciton bands) in semiconductor nanostructures such as nanocrystals, quantum wires, wells, and carbon nanotubes. Our general analysis of 2D double-quantum coherence resonances has demonstrated that the interband Coulomb interactions lead to new cross-peaks whose appearance can be interpreted as a result of exciton and biexciton state mixing. The presence of the strongly coupled resonant states and weakly coupled background of off-resonant states can significantly simplify cross-peak analysis by eliminating the congested background spectrum. Our simulations of the 2D double-quantum coherence signal in PbSe NCs have validated this approach.
利用带间激子散射模型，我们推导出了一组封闭的方程，用于确定二维双量子相干信号，该信号对半导体纳米结构（如纳米晶体、量子线、阱和碳纳米管）中的带间库仑相互作用（即导致激子和双激子带之间耦合的多体库仑相互作用）敏感。我们对二维双量子相干共振的综合分析表明，带间库仑相互作用导致了新的交叉峰的出现，这些交叉峰的出现可以解释为激子和双激子态混合的结果。强耦合共振态和弱耦合非共振态的背景的存在，可以通过消除拥挤的背景光谱，显著简化交叉峰分析。我们在 PbSe NCs 中对二维双量子相干信号的模拟验证了这种方法。
