Dynamical Confinement and Magnetic Traps for Charges and Spins

Abstract

We use the effective field theory approach to systematically study the dynamics of classical and quantum systems in an oscillating magnetic field. We find that the fast field oscillations give rise to an effective interaction which is able to confine charged particles as well as neutral particles with a spin magnetic moment. The effect is reminiscent of the renown dynamical stabilization of charges by the oscillating electric field and provides a foundation for a new class of magnetic traps. The properties characteristic to the dynamical magnetic confinement are reviewed.

Figures (3)

• Figure 1: The trajectories of a charged particle in the three-dimensional magnetic trap for (a) $\omega_B/\omega =1/100$, (b) $\omega_B/\omega =1/10$, and (c) $\omega_B/\omega =1$. As the scale ratio increases, the motion transforms from quasiperiodic to chaotic, but remains confined.
• Figure 2: The coordinates $x$ (short dashed), $y$ (long dashed), and $z$ (solid line) of a charged particle in the three-dimensional magnetic trap as functions of $\omega t$ for (a) $\omega_B/\omega=1/100$, (b) $\omega_B/\omega =1/10$, and (c) $\omega_B/\omega =1$, corresponding to the trajectories in Fig. \ref{['fig::1']}. For $\omega\gg\omega_B$ the large-scale oscillation frequencies are $\omega_B/2^{3/2}$ and $\omega_B/2$, in agreement with Eq. (\ref{['eq::Veffcharge3d']}).
• Figure 3: A trajectory of a charged particle in the two-dimensional magnetic trap for $\omega_B/\omega =1/10$. The excess micromotion orthogonal to the displacement from the induced electric field nodal point at the origin can be clearly identified.