LSAM – Advanced Spectroscopy and Microscopy Lab

Researchers at the Advanced Materials Spectroscopy Laboratory (LSAM) study the physical and chemical phenomena and processes occurring, at the atomic, nanometric, and micrometric scales, on material surfaces.

Experiments are conducted within an ultra-high vacuum (UHV) chamber system housing scientific instruments for experiments based on both spectroscopic and microscopic techniques.

Sources of ultraviolet radiation, X-rays (monochromatized), electrons, and ions, in conjunction with an electron analyzer, allow investigation of the electronic structure, chemical composition, and elementary electronic excitations of the samples.

Additionally, a scanning tunneling microscope (STM) enables reconstruction of the surface topography of the samples under study with atomic resolution, i.e., on the order of a tenth of a billionth of a meter. The microscope can also operate as an atomic force microscope in non-contact mode.

Prior to spectro-microscopic measurements, the crystalline surfaces of the samples are made as planar and ordered as possible by removing contaminant atoms from the outermost layer through cleavage or sputtering (ion bombardment). Samples subjected to sputtering are subsequently recrystallized via a specific thermal treatment (annealing). Surfaces are then studied in their natural state or functionalized through gas adsorption, or deposition of molecules, atoms, or metallic/molecular films.