Isotope effects in the harmonic response from hydrogenlike muonic atoms in strong laser fields

摘要

High-harmonic generation from hydrogenlike muonic atoms exposed toultraintense high-frequency laser fields is calculated. Systems of low nuclearcharge number Z are considered where a nonrelativistic description applies. Bycomparing the radiative response for different isotopes we demonstratecharacteristic signatures of the finite nuclear mass and size in the harmonicspectra. In particular, for Z>1, an effective muon charge appears in theSchr\"odinger equation for the relative particle motion, which influences theposition of the harmonic cutoff. Cutoff energies in the MeV domain can beachieved, offering prospects for the generation of ultrashort coherentgamma-ray pulses.