Growth of High-Quality Superconducting FeSe_0.5Te_0.5 Thin Films Suitable for Angle-Resolved Photoemission Spectroscopy Measurements via Pulsed Laser Deposition

High-quality superconducting FeSe_0.5Te_0.5 films are epitaxially grown on different substrates by using the pulsed laser deposition method. By measuring the transport properties and surface morphology of films grown on single-crystal substrates of Al₂O₃ (0001), SrTiO₃ (001), and MgO (001), as well as monitoring the real-time growth process on MgO substrates with reflection high energy electron diffraction, we find the appropriate parameters for epitaxial growth of high-quality FeSe_0.5Te_0.5 thin films suitable for angle-resolved photoemission spectroscopy measurements. We further report the angle-resolved photoemission spectroscopy characterization of the superconducting films. The clearly resolved Fermi surfaces and the band structure suggest a sample quality that is as good as that of high-quality single-crystals, demonstrating that the pulsed laser deposition method can serve as a promising technique for in situ preparation and manipulation of iron-based superconducting thin films, which may bring new prosperity to angle-resolved photoemission spectroscopy research on iron-based superconductors.