Realization of Single Attosecond Pulse Generation in Multi-Cycle Regime through Modulation of Carrier Wave

TL;DR

This paper proposes a new physical mechanism for generating single attosecond pulses in a multi-cycle regime by modulating the carrier wave, enabling control over high harmonic generation spectra and pulse coherence.

Contribution

It introduces a novel method to produce single attosecond pulses in multi-cycle regimes through carrier wave modulation, verified with tri-color pulse simulations.

Findings

Single attosecond pulses can be generated in multi-cycle regimes.

Carrier wave modulation controls high harmonic spectra.

High coherence photons near the cutoff are localized at pulse center.

Abstract

An intuitive physical mechanism for single attosecond pulse generation in multi-cycle pulse regime is proposed. We suggest that the continuum spectra of HHG can be controlled through the modulation of carrier wave, while keeping the multi-cycle envelope unchanged approximately. By increasing the time interval between the adjacent maximum return kinetic energy peaks, the kinetic energy of the side peaks will be apparently suppressed by the multi-cycle envelope. The photons with energies near the cutoff burst only at the pulse center with high coherence, which contribute to the generation of single attosecond pulse. We verify this mechanism by using a multi-cycle tri-color pulse as driver field.