Ricerc@Sapienza

1) The laboratory is devoted to the experimental investigation of the electronic band structure of surfaces and two-dmensional (2D) materials by means of high-resolution angle-resolved ultraviolet photoelectron spectroscopy (ARPES). The ARPES apparatus, working at high energy and angle resolutions, operating at low temperatures, is contained into an ultra-high-vacuum (UHV) chamber, UHV-connected to a preparation chamber equipped with several other characterisation methods and ancillary facilities for samples preparation and 2D materials growth, and is provided with a small UHV chamber for a fast load-lock introduction.

Main characteristics of the apparatus:
• ARPES hemispherical electron analyser: Scienta SES-200, 4 meV best energy resolution, <0.1◦ angular resolution, 1-50 eV pass-energy range, multi-channel detector (MCD, ±8◦ angular span and 10% of pass- energy energy span);

• ARPES photon source: Omicron-Scienta VUV-5000 monochromatised MW-excited He source, main lines HeIα at 21.218 eV and HeIIα at 40.814 eV, up to HeIIδ at 52.241 eV;
• ARPES manipulator: 5-degrees of freedom UHV manipulator, with precision rotation of the azimuthal and polar angles, cryostat to liquid nitrogen temperature, electron-bombardment heater up to 1200◦C;
• Low-Energy Electron Diffraction (LEED): Specs retractable ErLEED system, with LEED and Auger modules;
• Ion Gun: Omicron ISE10 0.2-5 keV energy range, Ar ion source;
• Mass Spectrometer: residual gas analyser SRS RGA 300, 1-300 a.m.u. range;
• Gas line, equipped with several ports for small bottles and UHV-connected through a leak-valve to the main chamber; oxygen and C2H4 sources mounted, the latter for graphene preparation on metals via temperature programmed growth;
• Organic-molecular beam epitaxy (O-MBE) cells; high-temperature electron-bombardment based evaporator for transition metals; quartz crystal thickness monitor; cleaver, other ancillary facilities for sample preparation, etc.

Further information at:

https://drive.google.com/file/d/1h3-oAaZC7jxvg1d4j3Zhfrrl-A1-n2Hu/view

2) XPS, LEED/AES and TDS apparatus contained into an ultra-high-vacuum (UHV) chamber, UHV- connected to a small chamber for a fast load-lock introduction, along with several other characterisation methods and ancillary facilities for samples preparation and cleaning, atomic/molecular beam epitaxial evaporators.

Main characteristics of the apparatus:
• XPS hemispherical electron analyser: VG Microtech Clam-2, pass-energy range: 10-200 eV, single-channel detector;
• XPS photon source: PSP double-anode X-ray source, emission lines AlKα (1486.6 eV) MgKα (1253.6 eV);
• XPS UHV manipulator: 4-degrees of freedom, cryostat (>77 K), electron-bombardment heater (≤1200 K);
• Low-Energy Electron Diffraction (LEED): Omicron SpectaLEED system, with LEED and Auger modules;
• Ion Gun: Omicron ISE10 0.2-5 keV energy range, Ar ion source;
• Mass Spectrometer: residual gas analyser SRS RGA (1-300 a.m.u.); linear T ramp for TDS acquisition;
• Gas line equipped with several ports, UHV-connected through a leak-valve to the main chamber; O, H and C2H4 sources;
• Organic-molecular beam epitaxy (O-MBE) cells, with thermocouple control; quartz crystal thickness monitor; high-temperature electron-bombardment based evaporator for transition metals.

Further information at:

https://drive.google.com/file/d/1TN2ZddLMwsMmN983ZBc7g2DAWQMAniW0/view