So the goal is to a build a device that will redirect field lines from earths magnetic field at the magnetic north pole into a point.
The goal is to maximize the area / amount of magnetic flux redirected while minimizing the amount of material used in this device.
Initially the thought I had was a hollow cone shaped magnet whose magnetic orientation is the same as the earth's would be ideal for this. Image below with magnetic field lines in violet drawn for how I believe will happen the field would interact with the cone:
Naturally an idea arises. Why use a cone at all? We could after all just have a flat disk that covers the same area and then just have a prong extending from it in the center to minimize the surface area used.
So I came up with this idea:
But even then... why even have the disk? could we perhaps just have a cage of tentacles try to attract and trap magnetic field lines without even having a disk? So now the amount of material used scales linearly as opposed to quadratically
So is it possible to do better than this for minimizing the amount of material one uses and still successfully redirecting field lines?