# Generation of isolated attosecond pulses by polarization gating of high-order harmonic emission from H$_2^+$ in intense ultrashort laser fields

## TL;DR

This study demonstrates how polarization gating using elliptically polarized laser fields can generate isolated attosecond pulses from H$_2^+$ molecules, with control over pulse duration and intensity.

## Contribution

It introduces a quantum-mechanical approach to optimize polarization gating for single attosecond pulse generation from H$_2^+$ in intense laser fields.

## Key findings

- Single attosecond pulses can be isolated using polarization gating.
- Ellipticity of the laser field influences pulse duration and intensity.
- Conventional polarization gating effectively produces intense isolated attosecond pulses.

## Abstract

Quantum-mechanical investigation is presented to study single attosecond pulse generation by gating high-order harmonic emission from H$_2^+$ molecule in intense laser pulses with time-dependent ellipticity. The high-order harmonic generation from H$_2^+$ molecule in superposition of a left and a right-hand circularly polarized Gaussian pulse is studied and the effect of time duration and carrier-envelope phase of laser field on single attosecond pulse generation is investigated. Using laser field formed by combination of a left and a right-hand elliptically polarized Gaussian pulse, the effect of ellipticity of field on duration and intensity of generated attosecond pulses is studied. The numerical calculations show that, with the conventional polarization gating, an intense single attosecond pulse can be isolated from the pulse train emitted by H$_2^+$ molecule in the laser field.