What is the typical resistance for GMR in 3-layer Fe-Cu-Fe configuration?

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The typical resistance for giant magnetoresistance (GMR) in a 3-layer Fe-Cu-Fe configuration at room temperature (300K) with layer thicknesses of 30 Å for Fe and 20 Å for Cu is estimated to be in the range of tens to hundreds of ohms. This estimation is based on the bulk resistivity of copper and iron, where the sheet resistance can be calculated by dividing the bulk resistivity by the film thickness. However, this method becomes less accurate when dimensions approach the electron mean free path, particularly for copper at room temperature, which is approximately 300 Å.

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for giant magnetoresistance with 3 layers suppose Fe-Cu-Fe, and suppose we take room temperature (300K) and moderate layer thickness (eg Fe = 30 Amstrong, Cu = 20 Amstrong),

what is the typical magnetoresistance we get? I mean the maximum resistance (in ohms) when the magnetization of the FM layers are antiparallel (i am not asking the GMR ratio delta r/ro).

Is it in the order of few tens of ohms, hundreds of ohms, kilo ohms ?

i just want rough estimate. all references i saw talk about the gmr ratio only, not the actual resistance.

thank you.
 
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michaeltorrent said:
Is it in the order of few tens of ohms, hundreds of ohms, kilo ohms ?
i just want rough estimate. all references i saw talk about the gmr ratio only, not the actual resistance.
You can make a rough estimate using the bulk resistivity of copper and/or of iron. So it depends on the other dimensions of the film (length and width).

If we just take the sheet or surface resistance of a 10 Å film, one would divide the bulk resistivity by the thickness: (10^-8 Ohm.m)/(10^-9 m) = 10 Ohm (per square).

(Of course, this does not really work when dimensions become smaller than the electron mean free path. I copper at room temperature, this is about 300 Å. It only gives a rough estimate.)
 
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hey .. guys . ... I was wondering if anyone did some exerimental work on GMR .. I have been trying to get GMR in nanowires but have not been successful .. I have tried varying pulse timing but have had no luck ... Can anyone help me out??