We're working with a Ti:Sapphire Laser pulsed at 80MHz. Our setup in a nutshell is having the main beam separated into a main beam that will excite the sample of XYZ head on, and a probing beam that will hit the sample at some angle, and be reflected off and into a prism that will separate the linear and nonlinear parts into 2 PMT's respectively. Our plan is to vary the wavelength of this from 700-1000nm.
My Problem
I've been told that as we vary the wavelength from 700-1000nm the linear and nonlinear beams will walk around some, so they will not line up with the PMT.
Where will the angles change due to wavelength? and how much travel can I expect?
Also, if the above is true, how can I rig my setup so that i don't have to move the PMT's everytime I change the wavelength? A concave mirror, rotating stage?
My Problem
I've been told that as we vary the wavelength from 700-1000nm the linear and nonlinear beams will walk around some, so they will not line up with the PMT.
Where will the angles change due to wavelength? and how much travel can I expect?
Also, if the above is true, how can I rig my setup so that i don't have to move the PMT's everytime I change the wavelength? A concave mirror, rotating stage?