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Journal of the Optical Society of America B

Laser shaping of photoelectron angular distributions from Rydberg atomic states

R. Parzyński, Andrzej Grudka

Published Jul 1, 1999• 1 citation
Publisher

Abstract

When the Rydberg atom prepared in an n0s state (n0≫1) is exposed to a sufficiently intense laser pulse of a duration not exceedingly short compared with the initial-state Kepler period, the resulting photoelectron angular distributions are not only governed by the p partial wave but are shown to be shaped by higher-order waves as well, provided that the frequency assumed permits the higher-angular-momentum Rydberg states about the initial n0s state to be involved in the process owing to multiple resonant Raman transitions.

DOI
10.1364/josab.16.001039

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When the Rydberg atom prepared in an n0s state (n0≫1) is exposed to a sufficiently intense laser pulse of a duration not exceedingly short compared with the initial-state Kepler period, the resulting photoelectron angular distributions are not only governed by the p partial wave but are shown to be shaped by higher-order waves as well, provided that the frequency assumed permits the higher-angular-momentum Rydberg states about the initial n0s state to be involved in the process owing to multiple resonant Raman transitions.
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Numerical integration of the Schr\"odinger equation for the resonant single-photon excitation from the 1s1s1s to 10p10p10p state in atomic hydrogen has been used to produce solutions converged to a precision of a few parts per million. At all intensities investigated (in the range 10−−100TW/cm2),10--100{\mathrm{T}\mathrm{W}/\mathrm{c}\mathrm{m}}^{2}),10−−100TW/cm2), the population in the states having angular momentum higher than l=1\mathcal{l}=1l=1 after a narrowband (500 fs) laser pulse are found to be neglible. This shows that off-resonant states can effectively suppress Raman-like transitions to degenerate states of higher angular momentum. Instead of such mixing, strong Rabi-like oscillations between 1s1s1s and the np\mathrm{np}np Rydberg series are observed.
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