Although it seems that obtaining the quantum properties of light from classical calculations is a self-contradictory claim, it is shown here that this can be achieved by a unified mechanism which relies on a non-Hermitian Floquet theory. The mechanism governs the three distinct measurements of high-order-harmonic-generation spectra (HGS), above-threshold ionization (ATI), and IR photon number distribution. Here, the conditions that enable the calculations of HGS and ATI spectra for atoms interacting with high-intensity laser fields from photon statistics are first derived. Through a non-Hermitian theoretical simulation, the regimes where there is correspondence between the HHG and ATI spectra and annihilated pump photons (with postselection) are identified. Consequently, the HGS and ATI spectra, as detected by XUV detectors, can be obtained by monitoring the fluctuations of the infrared absorbed photons.

Close

PrevNext

View figure in article

• Atomic & molecular processes in external fields