Carrier-envelope-phase control of plasmonic-field enhanced high-order harmonic generation
Abstract Plasmonic field-enhanced high-order harmonic generation (HHG) is investigated theoretically using the solutions of the three-dimensional time-dependent Schrödinger equation and a (semi)classical three-step model. Plasmonic field is modeled by a spatially inhomogeneous field with a time-dependent cosine squared pulse envelope. The dependence of the HHG yield on the carrier-envelope phase (CEP) is investigated. It is shown that the position of the cutoff of the HHG spectra is very sensitive to the value of CEP and that for the inhomogeneous field the dependence on the CEP is modulo. This enables both the CEP control of the plasmonic field-enhanced HHG and the determination of the CEP modulo by the measurement of the HHG cutoff position. Contrary to the homogeneous field case, for inhomogeneous field the difference between the maximum and minimum HHG cutoff (for the CEP in the interval from 0 to) remains substantial even for pulses longer than 10 optical cycles.