Dear Bashir Footuhi,

There are several methods regarding your question. One of them is XED, but this approach has several advantages over heavier materials. But It also has a lot of limitations compared resolution of measurements. My suggestion is looking for the integration method and the curve fitting method, which are derived from EELS. Be careful faster detection has a limitation overall the process of determining transitions. (Remember: Type of materials  control your choices).

I hope this answer will help you.

Best regards

Musab Tr

EELS can be sub ms if needed. All depends on the spatial and spectral resolution you want for a given signal to noise ratio. Goind sub-100 nm with a reasonable spectral resolution (say 100 meV, an already good resolution for plasmon which have >100 meV fwhm in general), I am not aware of a more efficient technique than EELS in a STEM (in general), if your samples is adapted to STEM (thin enough, meaning 100 nm thick or less typically)

Dear Kociak

Thanks for your detailed response to the question. I am interested in measuring interband pi  plasmons in monolayer graphene sheets in a fast way (for sensing applications). Because of strongly localized plasmons (interband) in graphene (almost smaller than 5 nm), I think we need high resolution EELS.  

Oh, this is in view of applications... Then I doubt using electrons make sense. EELS in the STEM is quite costly, and not versatile if you think in terms of doing a device (if I get it right).

Yes, it is true and that is exactly why I am searching for another method similar to EELS