A general formula for phonon-assisted n-photon absorption in solids is obtained by (n + 1)-th order perturbation technique. The complicated calculation process for transition element of n-photon absorption is simpl...A general formula for phonon-assisted n-photon absorption in solids is obtained by (n + 1)-th order perturbation technique. The complicated calculation process for transition element of n-photon absorption is simply demonstrated by a diagram approach that is proposed in this work. We find that the transition element for the n-photon absorption has a simple form, i.e., it is just the first term of the n-th order fist kind Bessel function.展开更多
基金Project supported by the National High Technology Research and Development Program of China (863 Program) (Grant Nos. 2007AA804233 and 2008AA804050)the Fundamental Research Funds for the Central Universities (Grant Nos. ZYGX2009J046 and ZYGX2009X007)
文摘A general formula for phonon-assisted n-photon absorption in solids is obtained by (n + 1)-th order perturbation technique. The complicated calculation process for transition element of n-photon absorption is simply demonstrated by a diagram approach that is proposed in this work. We find that the transition element for the n-photon absorption has a simple form, i.e., it is just the first term of the n-th order fist kind Bessel function.