Recent content by excalibur313

I am trying to calculate what we'd expect the uncertainty in energy would be for an electron in a hydrogen atom where it was confined to its usual radius (120 pm) versus if we confined it to the width of a proton (.88 fm) to try and make an argument about why the electron does not fall into the...

Hi there, Thanks for the response. The question that I still have about that relation is that it implies that I should be able to achieve any diameter beam size for a lens of a given numerical aperture when in fact experimentally I don't find that to be the case. When I move the distance...

Hi Everyone, I am trying to find a formula that relates numerical aperture of a lens to the beam diameter that it would collimate a point source from. I could also do this from the effective focal length if that is easier. Thanks for your help!

I'm interested in the 300-500 nm range. So do you mean that in order to theoretically capture ordinary/extraordinary axes you have to use a tensor dielectric function? Is that required when calculating waveguiding effects? I only mentioned it because when searching for dielectric constants...

Hi Everyone, I am trying to find the real and imaginary dielectric constants for TiO2 (rutile) as a function of wavelength. Could anyone suggest a good place to find something like this? Palik has a nice book but it is incomplete, so I'm not sure if there is something newer. Also, could...

Its a collective oscillation of the electron density in a metal. It's most prominent in Au, Ag, and Cu, possibly due to the low imaginary part of the dielectric constant which means that the oscillations are more pronounced and less dampened.

Hi Everyone, I am a second year graduate student in physical chemistry at a top tier university. As an undergrad, I took Calculus 1-3 during my first two years, but then I didn't take any more because it wasn't required for my major and I was told that I didn't really need it. (I just took...

Hi Everyone, I am giving a talk on group theory as related to spectroscopy (IR & Raman) and I was curious about how to explain the jump from knowing which modes in the charcter table are Raman active to predicting what kind of vibration they will have. For example the Td point group has raman...

Hey Everyone. I am doing a project proposal where I am calculating the coupling efficiency between a quantum dot and a wire and I need to enter in values for the dielectric constant of the wire and the surrounding medium. I am working off a paper (doi:10.1103/PhysRevB.76.035420) where he uses...

Hey Everyone. I am doing a project proposal where I am calculating the coupling efficiency between a quantum dot and a wire and I need to enter in values for the dielectric constant of the wire and the surrounding medium. I am working off a paper (doi:10.1103/PhysRevB.76.035420) where he uses...

I think so, but I am covering it in quantum mechanics. Thanks for the help!

Hi everyone. I was curious how I could integrate a matrix. Is it just as simple as separately integrating each of the entities of the matrix, or is it more complex than that?

Okay, well the rate of fret is proportional to K^2 where: K=3(p1.r)(p2.r)-(p1.p2) Where p1 and p2 are the transition dipoles and r is a vector pointing from the center of p1 to the center of p2. r remains constant so I have to find <k^2> so I basically want to integrate over all orientations...

Thanks a lot for your help, but I guess I am wondering what the best way to approach this problemis. The idea is that the resulting value of this dot product is based on the angle between them. (Where it will be a bigger value if they are lined up parallel) so it isn't really apparent to me...

Does anyone know what the geometrical interpretation of a dot product in 3-D is? I am calculating the dot product between two vectors in 3d and need to use the |a||b|cos(theta) interpretation basically, but that is for 2d. Can I just tack on an additional cos(theta2)? Thanks a lot for your...