Electronic holography is a transmission electron microscopy (TEM) technique that can provide a range of information about a material's properties, such as electrical fields, magnetic fields, and crystal deformation. However, the reconstruction method traditionally used to obtain an interpretable image from holograms recorded during observation requires the use of a filter that limits the spatial resolution of the image obtained.

Researchers at Leti, a CEA Tech institute, used a new reconstruction method called phase shifting to get the microscope's full resolution in the final image. HoloView* software uses a different mathematical method to process the holograms, doing away with the need for filters that limit image resolution. The easy-to-use software also manages hologram acquisition on the microscope, making the new processing method possible.

By using the technique in conjunction with hologram summation - also developed by Leti - and integrating it into the software, both the sensitivity and spatial resolution of the measurement are improved, making it possible to see details of a sample with nanometric (and, in some cases, sub-nanometric) resolution and a high degree of precision. These advances will create new opportunities to use electronic holography for characterization purposes, especially in innovative fields like optoelectronics, magnetic memory, and microelectronics.

*Developed with ERC funding under the HoloView project