  Plasmons are elementary quantum excitations of conducting materials with
Fermi surfaces. In two dimensions they may carry a static dipole moment that is
transverse to their momentum which is quantum geometric in nature, the quantum
geometric dipole (QGD). We show that this property is also realized for such
materials confined in nanowire geometries. Focusing on the gapless,
intra-subband plasmon excitations, we compute the transverse dipole moment Dx
of the modes for a variety of situations. We find that single chiral fermions
generically host non-vanishing Dx, even when there is no intrinsic gap in the
two-dimensional spectrum, for which the corresponding two-dimensional QGD
vanishes. In the limit of very wide wires, the transverse dipole moment of the
highest velocity plasmon mode matches onto the two-dimensional QGD. Plasmons of
multi-valley systems that are time-reversal symmetric have vanishing transverse
dipole moment, but can be made to carry non-vanishing values by breaking the
valley symmetry, for example via magnetic field. The presence of a
non-vanishing transverse dipole moment for nanowire plasmons in principle
offers the possibility of continuously controlling their energies and
velocities by the application of a static transverse electric field.
