The Pulsar Engineering Community Board

Hello Luc and Board,

I'm looking to build either the starter or performance edition of the OpenRaman project. We want to take spectra of graphene samples and was wondering as to the suitability of OpenRaman for this.

The graphene samples we will take is a mixture of few-layer and multi-layer graphene.

Obviously high SNR and a deeply cooled CCD are going to be the things of priority.

If it is suitable, would the starter edition be enough or would we need the performance edition?

As a side-question, would it be feasible to pull a vacuum (two-stage pump) so that the CCD can be further cooled down without a threat of condensation?

Thank You

Hi,

I have no direct experience with graphene but this is a question that pops up relatively often.

I wouldn't use the starter edition but one of the method below:

• https://www.open-raman.org/cni-mgl-iii- ... er-review/
• https://www.open-raman.org/fiber-coupled-laser-update/

About the CCD question: the current camera is not compatible with intense TEC cooling because it is not sealed and you will get condensation when going below a critical temperature (typ 10°C depending on your local humidity levels). I would recommend against CCD as they are a thing of the past, back-thinned CMOS having replaced them in all applications.

There are a few TEC cooled CMOS cameras but I don't have direct experience with them (yet). That being said, it's on my short list! There are a few options there but I was personally looking at Morovian cameras (brand).

Hi Luc,

I actually already have a fiber laser with a 0.1 nm linewidth, but it outputs to free-space. I think the performance edition baseplate would still be suitable, but please correct me if I am wrong.

For the CCD vs CMOS, I was talking to a professor that builds out these Raman spectrometers and he recommended against the CMOS because of high noise with longer integration times. Can you chime in on this?