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kishtr
Switzerland
3 Posts |
 Posted - 08/31/2015 : 11:38:04 AM
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Hello All,
I have been trying to fit an equation to a nonlinear curve but haven't been able to make a good fit till now. hence, I thought I might take the help of this forum to succeed in it.
I have attached the equation and the data file in the post.
Looking forward to your suggestions,
Thanks
KT
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Edited by - kishtr on 08/31/2015 11:44:27 AM |
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lkb0221
China
497 Posts |
Posted - 08/31/2015 : 12:09:27 PM
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Hi,
Can you provide more details about this formula? To me it looks like over-parameterized (Y = A * X^2).
Zheng |
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kishtr
Switzerland
3 Posts |
Posted - 08/31/2015 : 12:53:49 PM
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Hi Zheng,
Yes, certainly:The formula is used to extract inelastic and elastic scattering rates in the Weak/Weak-Anti localization regime of a semiconductor exposed to low magnetic fields.
In short: Observing longitudinal resistance (Y axis) at Low magnetic fields(X axis)
The constants are:
e - electron charge - 1.6e-19
h - planck constant - 6.626e-34
hbar - 1.023e-34
D - Diffusion constant - 0.605 m^2/s
Rho - 14724 Ohms
pi - 3.14
B - X axis - Magnetic field sweep
Delta Rho - Resistivity
T-phi , Ti and T-star : Are all the parameters to extracted via the fit - These are the various elastic and inelastic scattering rates
Indeed, Origin fit does say that the parameters could have been over parameterized but I am not sure how to overcome the issue.
I will be glad to provide further details,
Best,
KT
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lkb0221
China
497 Posts |
Posted - 08/31/2015 : 1:55:50 PM
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Do you also have some roughly estimate (or range) of those three parameters?
The fitting needs some initial value to start with. |
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kishtr
Switzerland
3 Posts |
Posted - 09/01/2015 : 03:37:02 AM
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Hello,
Yes indeed :
10E-17 < Tphi < 10E-8
10E-17 < Ti < 10E-8
10E-17 < Tstar < 10E-8
Thanks and Best Regards,
Kishan |
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Topic |
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Non Linear Curve Fit