  The friction force on a test particle traveling through a plasma that is both
strongly coupled and strongly magnetized is studied using molecular dynamics
simulations. In addition to the usual stopping power component aligned
antiparallel to the velocity, a transverse component that is perpendicular to
both the velocity and Lorentz force is observed. This component, which was
recently discovered in weakly coupled plasmas, is found to increase in both
absolute and relative magnitude in the strongly coupled regime. Strong coupling
is also observed to induce a third component of the friction force in the
direction of the Lorentz force. These first-principles simulations reveal novel
physics associated with collisions in strongly coupled, strongly magnetized,
plasmas that are not predicted by existing kinetic theories. The effect is
expected to influence macroscopic transport in a number of laboratory
experiments and astrophysical plasmas.
