[7a-A405-1~10] 3.12 Nanoscale optical science and near-field optics

[7a-A405-9] Theory of Non-resonant Effect in Near-filed Optics II:Approach to a Base of Dressed Photon employing Non-linear Response Theory

〇Itsuki Banno¹, Motoichi Ohtsu^2,3 (1.Univ. of Yamanashi, 2.Univ. of Tokyo, 3.RODreP)

Keywords:non-linear near-field optics, non-resonant condition, dressed photon

We have been fomulated the response unction for a small-scale many-electron system located in the vicinity of the nanostructure as the light source. The linear and non-linear response functions relate the scalar and vector potentials (as the cause) to the charge and current densities (as the result). For example, the second order non-linear response function in the form of Heisenberg operator is derived as the 3rd order functional derivative of the action integral with respect to the scalar and vector potentials, and the charge conservation law and the gauge invariance are guaranteed. In this presentation, the recursive formula between the n-th and (n+1)-th order non-linear response functions is addressed. As an application, we will pointed out that the optical phonon may play an important role under a non-resonant condition in the near-field optics and will try to give a theoretical base for the relationship between the dressed photon and phonon from the first principle; the dressed photon have been used in various experiments performed by T. Kawazoe, M. Ohtsu, et. al.