Wattage of LASER needed for Raman spectroscopy

[sbrothy]

I'm currently using this document to purchase the parts I need. Being no expert, and looking on the table of the 532nm laser diodes used, it doesn't seem to matter much what wattage the laser should be. Is there any advantages to using either a low wattage or high wattage laser, apart from the heat deposited in the appliance?

 

[Borek]

Intensity of Raman scattered photons is several orders of magnitude (wikipedia article suggests 10^-6 range) lower than the intensity of the exciting photons, which makes detecting them difficult. My bet is you want as strong light source as possible (or, at least, you need to estimate whether your setup will be capable of detecting anything and filtering the noise from the original source away).

 

[sbrothy]

A procedure for filtering the noise is included in the paper. OTOH, from the paper, it doesn't seem to matter much which laser is actually used. I already have a couple of 650nm lasers. I could try with those....

 

[sbrothy]

Intensity of Raman scattered photons is several orders of magnitude (wikipedia article suggests 10^-6 range) lower than the intensity of the exciting photons, which makes detecting them difficult. My bet is you want as strong light source as possible (or, at least, you need to estimate whether your setup will be capable of detecting anything and filtering the noise from the original source away).

So if I understand correctly 100mW is better than 5mW, right?

EDIT: And yes I realize how basic this question is. I just want to be sure it's worth the trouble, because a private person isn't allowed to buy a 100mW laser here. I have a registered company though....

EDIT2: And these 2 threads of mine should be merged really...

 

[PhotonMartin]

100mW is perfect! most of them are tunable

 

[sbrothy]

100mW is perfect! most of them are tunable

Thanks for your answer. Comically, in the meantime I bought a 40W laser capable of burning through 1mm of stainless steel (on the first pass). I realize it has no application for what we're discussing I just went somewhat overboard laser-wise.