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The STEM group owns various equipment essentially dedicated to electron spectroscopy in Scanning Transmission Electron Microscopes (STEM). CHROMATEM, USTEM200 and VG Cold are available to external users through either French network METSA and/or the European network ESTEEM3.



CHROMATEM is a monochromated and Cs-corrected scanning transmission electron microscope designed and built by NION based on the HERMES model, and adapted to some Orsay STEM team specifications, making it a world-wide unique machine for electron and photon spectromicroscopy techniques with ultra-high energy and spatial resolution. CHROMATEM will address cutting-edge issues and target new problems, such as low-dimentional physical phenomena, quantum nano-optics, optoelectronic properties of semiconductor nanostructures and metal-insulator transitions. More details here.

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Developed by the NION company, the USTEM 200 is a C3 (spherical aberration of third order) and C5 corrected STEM received in 2011. It is fitted with a cold Field Emission Gun (CFEG) working from 60 keV to 200 keV. This allows to work with radiation sensitive (graphene...) material yet keeping a sub-atomic resolution, or to reach ultimate spatial resolutions with less radiation sensitive material (steels...). It is also fitted with an in house developed spectral-imaging and high speed, high sensitivity EELS detection system. Together with the good spectral resolution allowed by the FEG, it enables applications ranging from structure and chemical analysis of graphene like materials to atomically resolved electronic properties of interfaces of functional oxydes. More details here.

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VG Cold

Our first Vacuum Generator HB 501 is fitted with a CFEG which enabled a high brigthness, a sub-nanometer spatial resolution and a good (less than 0.3 eV) spectral resolution, making it ideal for medium resolution analysis applications. Although bought 30 years ago, the VG cold has been constantly improved with in-house made instrumentation, such as enhanced scanning, spectral imaging and EELS capabilities. More recently, it has been fitted with a Nitrogen cooled stage and a high throughput cathodoluminescence system. All these improvement make the VG HB 501 still very competitive if not unique for the structural and chemical analysis of fragile materials, and for the nanooptics studies at the nanometer scale.

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VG Lumière

The VG Lumière ("light" in french) is a VG HB501 devoted to nanooptics and instrumentation development. It is fitted with a new in house made light injection devices for Electron Energy Gain Spectroscopy.

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JEOL 2010

The JEOL 2010 is a high resolution conventional transmission electron microscope that can be operated between 80 to 200 kV. It is configured with a high brightness LaB6 electron sauce for HRTEM imaging and electron diffraction.

Computer cluster

The group is equiped with a computer cluster  mainly dedicated to parallel quantum mechanical calculations of materials properties at the nanometre scale. The cluster consists of 39 computer nodes equiped with Xeon processors (a total of 644 computing cores), 96 Gb of RAM per node and it runs under the Rocks cluster distribution.

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