Angular tunneling ionization probability of fixed-in-space H molecules in intense laser pulses

強レーザーパルス中でのH分子のトンネルイオン化角度分布

Staudte, A.*; Patchkovskii, S.*; Pavii, D.*; 赤木 浩; Smirnova, O.*; Zeidler, D.*; Meckel, M.*; Villeneuve, D. M.*; Drner, R.*; Ivanov, M. Yu.*; Corkum, P. B.*

Staudte, A.*; Patchkovskii, S.*; Pavii, D.*; Akagi, Hiroshi; Smirnova, O.*; Zeidler, D.*; Meckel, M.*; Villeneuve, D. M.*; Drner, R.*; Ivanov, M. Yu.*; Corkum, P. B.*

We propose a new approach to obtain molecular frame photoelectron angular distributions from molecules ionized by intense laser pulses. With our method we study the angular tunnel ionization probability of H at a wavelength of 800 nm over an intensity range of 2-4.510 W/cm. We find an anisotropy that is stronger than predicted by any existing model. To explain the observed anisotropy and its strong intensity dependence we develop an analytical model in the frame work of the strong field approximation. It expresses molecular ionization as a product of atomic ionization rate and a Fourier transform of the highest occupied molecular orbital filtered by the strong-field ionization process.