# Pulse-shape control of two-color interference in high-order-harmonic generation

## TL;DR

This paper demonstrates how a short, delayed 400-nm laser pulse can control interference effects in high-order harmonic generation from neon, enhancing yield and cutoff energy through pulse timing adjustments.

## Contribution

It introduces a novel approach using a short, delayed 400-nm pulse to manipulate electron trajectories and harmonic generation in neon, expanding control over HHG processes.

## Key findings

- Enhanced harmonic yield with 400-nm pulse inclusion
- Cutoff energy depends strongly on pulse delay
- Interference control modifies harmonic spectra

## Abstract

We report on calculations of harmonic generation by neon in a mixed (800-nm + time-delayed 400-nm) laser pulse scheme. In contrast with previous studies we employ a short (few-cycle) 400-nm pulse, finding that this affords control of the interference between electron trajectories contributing to the cutoff harmonics. The inclusion of the 400-nm pulse enhances the yield and cutoff energy, both of which exhibit a strong dependence on the time delay between the two pulses. Using a combination of time-dependent R-matrix theory and a classical trajectory model, we assess the mechanisms leading to these effects.