What is a high gradient magnetic field?

Also, how much telsa/gauss might it be?|||A gradient is basically the derivative, or the slope, of a field. So a high gradient field means that the field has a large slope. Or in other words, the magnitude of the field changes... a lot... as a function of position.





Let's say I have a magnetic field of 1 G at location A and it is 2 G at location B, which is 1 meter away. That is a low gradient field. There are two ways I can increase the gradient. I can increase the total magnitude. For example, if it is 1 T at A and 2 T at B, that is 10,000 times larger of a gradient, and that's a pretty big gradient. The second way is to decrease the size scale. Let's say it is 1 G at A but now it is 1 G at location C, which is 1 mm away from A. That is much larger slope, so this is 1000 times stronger gradient than the original gradient.





What exactly sets the boundary between not-high and high gradient depends on the application. For flux-gates, 1 G/mm is probably high. For particle accelerators, 1G/mm is probably pretty small. It all depends on what you are trying to do.