Define laser beam parameter
wavelength = 800.; intensity = 1e14; CEP = 0.;
envelope = Pulse.SinSquaredEnvelope(8)
polarization = Basics.RightElliptical(1)
omega = convertUnits("energy: from wavelength [nm] to atomic", wavelength)
intensity = convertUnits("intensity: from W/cm^2 to atomic", intensity)
A0 = Pulse.computeFieldAmplitude(intensity, omega)
beam = Pulse.PlaneWaveBeam(A0, omega, CEP)