High Harmonic Generation in Ionization of Magnetically Dressed Atoms APS Centennial Meeting Atlanta 1999 DAMOP Undergraduate Research Symposium High Harmonic Generation in Ionization of Magnetically Dressed Atoms Robert E. Wagner Freshman Intense Laser Physics Theory Unit Illinois State University www.phy.ilstu.edu/ILP

National Science Foundation Acknowledgment Undergrad researchers: P. Peverly, electron dynamics J. Braun, quantum simulations J. Csesznegi, graphics T. Shepherd, animations Advisors: Profs. Q. Su, R. Grobe Support: National Science Foundation Research Corporation ISU Honor’s Program

Scattered Light Spectra in Ionization w3 w2 wL wL w1 ? ? ? I(w) wL w

Relativistic Newton Equations RK-4 variable step size simulation Spectra of scattered light

Non-relativistic regime: E < 1 a.u.  = L L + M a (L + M = odd)  = L L (L = odd) Shifted atomic lines Laser Intensity w = wL Rapid ionization

Relativistic regime: E > 1 a.u.  = L L (L = even + odd) Laser Intensity Relativistic redshift

Magnetically dressed atoms Perturbative regime: E < 0.1 a.u. Non-rel. strong field: 0.1 < E < 1.0 a.u. Laser Intensity Relativistic magnetic resonances: E > 1.0 a.u.

Non-rel. Perturbative Regime: E < 0.1 (3,1,1) w = L wL + M w+ + N w- (L + M + N = odd) W = Cyclotron frequency

Analytically Soluble Model — exact

Relativistic Magnetic Resonances Typical Orbit Maximum displacement How do the spectra evolve as a function of W?

Summary - W=0 -> main features understood - Analytical model -> retardation effects in spectra - Novel rel. resonances enhance higher harmonics - Challenges ahead: coherence, quantum aspects... R. E. Wagner, Q. Su and R. Grobe, Phys. Rev. A (submitted) www.phy.ilstu.edu/ILP