XUV Phase Retarder

Our XUV Phase Retarder acts as a quarter waveplate to turn linear polarized XUV light into circular polarized light without introducing noticeable dispersion. The phase retarder achieves close-to-circular polarization of Pc=0.75 and obtains > 25% transmission around 66eV photon energy, where the Ni M2/M3 edge locates [1]. A broad spectral range from 40 to 85eV is supported to cover the M2/M3 edge of 3 transition metals - Fe, Co and Ni. The retarder uses a transmission optimized, four mirror grazing incidence reflection geometry that induces a quarter wave phase offset between -s and -p polarization component of a linear polarized input XUV beam. At the Ni M2/M3 transition up to 3% dichroism contrast is observed (i.e. > 85% of the theoretical value) [1]. A clear aperture of 3 mm will allow the low divergent XUV to pass through without clipping. Our XUV Phase Retarder is ideally geared to be combined with ultrafast high-harmonic XUV sources adding spin-sensitivity to conventional laser based pump-probe experiments via attosecond magnetic circular dichroism detection.

Aurora - XUV Phase Retarder
AURORA Grafik 1

Fig. 1: Phase and Transmission, p-Pol

AURORA Grafik 2

Fig. 2: Phase and Transmission, s-Pol

Key Product Features:

  • Create circular polarized XUV light without adding dispersion (ideal for attosecond applications)
  • Up to ≈ 40% max transmission
  • Broad spectral range covering 40 – 85 eV
  • Compact design, with minimum change in the delay line
  • Entrance and exit iris diaphragms for alignment
  • Easy to implement in existing setups