Sum-rules and quantum limits: nonlinear optics from first principles

摘要

Much progress has been made in improving the molecular hyperpolarizability by constructing larger structures with lots of pi-delocalized electrons. This bigger-is-better approach does not answer a more fundamental question of what intrinsic molecular properties yield the largest response. We introduce a novel analysis (the quantum limits analysis) which is simple to apply and combines first principles with experimental results. The quantum limits analysis allows us to determine the intrinsic nonlinear efficiency of a structure and highlights the underlying physical principles behind the nonlinear response of molecules.