Ravian
Newbie level 1
I am working on the problem of extraction of optical constants (complex refractive index etc.) of multilayer thin films. My typical samples consist of 4-5films on top of each other. The film of unknown optical constants is sandwiched between top and bottom layer. Usually top/bottom layers have their optical constants known.
I obtain transmission/reflection spectra using FTIR and R/T techniques in IR and visible range. I know that I can use transfer matrix method to determine optical constants and actually have tried to use a commercial software to do so. But there are certain complications which I am not able to overcome. What this commercial softare does is that it takes my experimental data, asks to provide guessed value of refractive index and after perorming iterative procedures (in which multiple reflection are taken into account) produces a theoretical transmittance curve. If that theoretical transmittance matches with my experimental curve then calculated refractive index is true. The problem is that my samples have optical gaps so refractive index and extinction co-effcients change with frequency of light. Therefore I have to divide my R/T data (which usually is huge comprising of more than 15000 rows) in to small intervals of wavelength of light (each interval is of around 5lines which makes more than 3000 intervals) and calculate refractive index of each interval individually. I have to spend hours in front of my computer and laptop which comes hard on my bones and muscles:-x:-(
What I am looking for is a software which automatically divides my R/T into small intervals, picks each interval one-by-one, asks me to provide a guessed value of refractive index/extinction coeffcients as input for each interval, performs iterations for TMM, produce thoretical R/T curve for me. Provisions of keeping either refractive index or extinction co-efficients constant should be in software because samples have optical gaps. If the produced R/T curve does not fit well with experiment then we need to repeat this whole operation.
I beleive I can write the code in matlab but the problem seems to be extremely difficult and I am not well versed with matlab or anyother programming language. Moreover it may take my precious time which I should be using to explain Physics of my samples. Sounds like a huge project? Is there any sofware like this available or at least someone can assist me to write a code?
I obtain transmission/reflection spectra using FTIR and R/T techniques in IR and visible range. I know that I can use transfer matrix method to determine optical constants and actually have tried to use a commercial software to do so. But there are certain complications which I am not able to overcome. What this commercial softare does is that it takes my experimental data, asks to provide guessed value of refractive index and after perorming iterative procedures (in which multiple reflection are taken into account) produces a theoretical transmittance curve. If that theoretical transmittance matches with my experimental curve then calculated refractive index is true. The problem is that my samples have optical gaps so refractive index and extinction co-effcients change with frequency of light. Therefore I have to divide my R/T data (which usually is huge comprising of more than 15000 rows) in to small intervals of wavelength of light (each interval is of around 5lines which makes more than 3000 intervals) and calculate refractive index of each interval individually. I have to spend hours in front of my computer and laptop which comes hard on my bones and muscles:-x:-(
What I am looking for is a software which automatically divides my R/T into small intervals, picks each interval one-by-one, asks me to provide a guessed value of refractive index/extinction coeffcients as input for each interval, performs iterations for TMM, produce thoretical R/T curve for me. Provisions of keeping either refractive index or extinction co-efficients constant should be in software because samples have optical gaps. If the produced R/T curve does not fit well with experiment then we need to repeat this whole operation.
I beleive I can write the code in matlab but the problem seems to be extremely difficult and I am not well versed with matlab or anyother programming language. Moreover it may take my precious time which I should be using to explain Physics of my samples. Sounds like a huge project? Is there any sofware like this available or at least someone can assist me to write a code?