  Most of 2D superconductors are of type II, i.e., they are penetrated by
quantized vortices when exposed to out-of-plane magnetic fields. In presence of
a supercurrent, a Lorentz-like force acts on the vortices, leading to drift and
dissipation. The current-induced vortex motion is impeded by pinning at
defects, enabling the use of superconductors to generate high magnetic fields
without dissipation. Usually, the pinning strength decreases upon any type of
pair-breaking. Here we show that in Rashba superconductors the application of
an in-plane field leads, instead, to an unexpected enhancement of pinning. When
rotating the in-plane component of the field with respect to the current
direction, the vortex inductance turns out to be highly anisotropic. We explain
this phenomenon as a manifestation of Lifshitz invariant terms in the
Ginzburg-Landau free energy, which are enabled by inversion and time-reversal
symmetry breaking and lead to an elliptic squeezing of vortex cores. Our
experiment provides access to a fundamental property of Rashba superconductors
and offers an entirely new approach to vortex manipulation.
