title: Quantum-orbit analysis for yield and ellipticity of high order harmonic generation with elliptically polarized laser field.
abstract: We perform a quantum-orbit analysis for the dependence of high-order-harmonic yield on the driving field ellipticity and the polarization properties of the generated high harmonics. The electron trajectories responsible for the emission of particular harmonics are identified. It is found that, in elliptically polarized driving field, the electrons have ellipticity-dependent initial velocities, which lead to the decrease of the ionization rate. Thus the harmonic yield steeply decreases with laser ellipticity. Besides, we show that the polarization properties of the harmonics are related to the complex momenta of the electron. The physical origin of the harmonic ellipticity is interpreted as the consequence of quantum-mechanical uncertainty of the electron momentum. Our results are verified with the experimental results as well as the numerical solutions of the time dependent Schrödinger equation from the literature.
authors.affiliation: Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaosong
authors.initials: X
authors.lastname: Zhu
authors.forename: Qingbin
authors.initials: Q
authors.lastname: Zhang
authors.forename: Meiyan
authors.initials: M
authors.lastname: Qin
authors.forename: Peixiang
authors.initials: P
authors.lastname: Lu
mesh_terms: D003198:Computer Simulation; D007834:Lasers; D008027:Light; D008962:Models, Theoretical; D012542:Scattering, Radiation