Spin- and angle-resolved inverse photoemission setup with spin orientation independent from electron incidence angle

A new spin- and angle-resolved inverse photoemission setup with a low-energy electron source is presented. The spin-polarized electron source, with a compact design, can decouple the spin polarization vector from the electron beam propagation vector, allowing one to explore any spin orientation at any wavevector in angle-resolved inverse photoemission. The beam polarization can be tuned to any preferred direction with a shielded electron optical system, preserving the parallel beam condition. We demonstrate the performances of the setup by measurements on Cu(001) and Au(111). We estimate the energy resolution of the overall system at room temperature to be similar to 170 meV from k(B)T(eff) of a Cu(001) Fermi level, allowing a direct comparison to photoemission. The spin-resolved operation of the setup has been demonstrated by measuring the Rashba splitting of the Au(111) Shockley surface state. The effective polarization of the electron beam is P = 30% +/- 3%, and the wavevector resolution is Delta k(F) less than or similar to 0.06 angstrom(-1). Measurements on the Au(111) surface state demonstrate how the electron beam polarization direction can be tuned in the three spatial dimensions. The maximum of the spin asymmetry is reached when the electron beam polarization is aligned with the in-plane spin polarization of the Au(111) surface state.

Automated summary

A new spin- and angle-resolved inverse photoemission setup with a low-energy electron source is presented, allowing for exploration of any spin orientation at any wavevector. The setup has a compact design and adjustable beam polarization direction, providing good energy and wavevector resolution at room temperature. The performance of the setup is demonstrated by measurements on Cu(001) and Au(111).