Preventing parasitics for wires?

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Summary:
It is possible to prevent parasitics for wires with this special material from a physics perspective?
This is related to a question that I asked here: https://physics.stackexchange.com/questions/650709/one-way-magnetic-shielding. Please take a look at the check-marked answer. There is a material that can act as a one-way magnetic/electric shield.

My question is if this material were to be used on wires, could it prevent parasitic capacitance and inductance?

My reasoning on why it can

This material can be used as a diode for magnetic fields, then it surely can prevent crosstalk between wires. This is because the changing magnetic field of the wires can only be emitted by them, and if both parallel wires have this shielding, then both can emit but not absorb each other's magnetic fields, thus preventing parasitic inductance.

And this material will also prevent parasitic capacitance because it allows the wire to emit the electric field outward, but no other neighboring wires can absorb this electric field (given they also have the 1-way shielding). Therefore, parasitic capacitance cannot happen as well.

Furthermore, self-capacitance and self-inductance of a wire cannot happen with this shielding because it blocks the magnetic field coming back to the wire and prevents the electric field to interfere with the current flow.

Is my reasoning valid or not? If yes, then it seems like this material would have numerous valuable and important applications in the real world.
 

Answers and Replies

  • #2
Baluncore
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Is my reasoning valid or not?
Invalid. The effective inductance and capacitance between two wires remains the same.

The presence of an image in a rotating cylinder, or a surface clad with non-reciprocal couplers will change the relationship between the two wires. You can cancel capacitance or inductance, but only at the cost of doubling the power requirement.
 
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  • #3
sophiecentaur
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Pay good attention to what @Baluncore says on this topic. With a name like his, he's just got to have a background of RF inductors. :wink:

There are many strategies to reduce crosstalk between transmission lines, based on geometry. A so-called Twisted Pair can help with E field crosstalk. Inverting the polarity of one pair of wires every few metres (or whatever) can help to cancel out the crosstalk. In telephone systems with many pairs of conductors, there are complicated patterns of polarity changes which mitigate crosstalk between all channels. This link is worth glancing at.
 
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@Baluncore "You can cancel capacitance or inductance, but only at the cost of doubling the power requirement."

So you can cancel out crosstalk (capacitance and inductance) with or without the material I linked? And why would you need to double the power requirement? Thanks for the link @sophiecentaur and your input.
 
  • #5
sophiecentaur
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So you can cancel out crosstalk
You can 'reduce' rather than cancel crosstalk. Any technique involving subtraction of one signal from another tends to be knife-edged. If the signal has any useful bandwidth, the impedances in a real system will vary over the band and that will involve choosing a frequency where it works best.
A 10dB reduction would not be hard but 60dB could be asking too much so the eternal Engineering question arises : how much do you need and how much are you prepared to spend, because it would all be down to quality of construction?
 

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