Trapping charged particles.
We jump straight into finding the equations of the fields involved — the magnetic field is simply
Now, taking the Lorentz force to be the only force acting on this system, Newton's law of motion states
Essentially, what we now have is a couple of differential equations. Notice that
Immediately we notice that the
With the known solution in terms of initial conditions
From the
Note that for each component, the reality of the situation means that all the values above has to be real. With that in mind, consider the equation
Owing to the linearity of the differential equation, we can define a
Using the ansatz
Solving for
Let us first consider the case where
By setting
Here I utilise the sympy
package in Python to solve for the coefficients:
>>> from sympy import *
>>> var('w_0 alpha beta omega Omega')
(w_0, alpha, beta, omega, Omega)
>>> wp = Symbol("w_0\'")
>>> coef = solve([
... w_0-alpha-beta,
... wp+I*((omega+Omega)*alpha + (omega-Omega)*beta)
... ], [
... alpha, beta
... ])
>>> print(latex(coef))
Placing the coefficients back into the equation,
For the ease of calculation, and in anticipation for purposes of coding, we form the following variables:
Which means
There is a possibility that
Then Equation
What we notice here, and also with Equation
From Equation
which we can find now that we have the solved equations of motion.