We introduce a new technique called 3D-ARRES, with which the full free elec- tron eigenstates above the vacuum energy of van der Waals materials can be imaged by resolving the landing energy and in...Show moreWe introduce a new technique called 3D-ARRES, with which the full free elec- tron eigenstates above the vacuum energy of van der Waals materials can be imaged by resolving the landing energy and in-plane momentum of reflected electrons in LEEM. Compared to ARRES, 3D-ARRES measures the whole first Brillouin zone and not only along the high symmetry axes. This is done by inte- grating the LEED pattern on the camera at different incidence angles and land- ing energies and fitting the data using image analysis techniques. By comparing the three-dimensional (3D) band structures ARRES measurements on both bulk MoS 2 and h-BN, 3D-ARRES is shown to be effective.Show less
Amethod to measure local tilt angles of two-dimensional materials in LEEM is developed. To create these local tilt angles graphene is stamped on top of pillars which are 55 nm high and 1 μm in...Show moreAmethod to measure local tilt angles of two-dimensional materials in LEEM is developed. To create these local tilt angles graphene is stamped on top of pillars which are 55 nm high and 1 μm in diameter. The measurement method uses an aperture to select a spot on the sample and moved the sample to measure all over the sample. These spots are measured in diffraction space. By analyzing all diffraction images, a magnitude and an orientation of local tilt angles are obtained. The spatial resolution of this method is bound by the size of the aperture. In this experiment a spatial resolution of 338 nm is achieved. The angular resolution depends on the locating method of the diffraction spot. In this experiment an angular resolution of one degree is achieved.Show less
