  Magnetic bimeron composed of two merons is a topological counterpart of
magnetic skyrmion in in-plane magnets, which can be used as the nonvolatile
information carrier in spintronic devices. Here we analytically and numerically
study the dynamics of ferromagnetic bimerons driven by spin currents and
magnetic fields. Numerical simulations demonstrate that two bimerons with
opposite signs of topological numbers can be created simultaneously in a
ferromagnetic thin film via current-induced spin torques. The current-induced
spin torques can also drive the bimeron and its speed is analytically derived,
which agrees with the numerical results. Since the bimerons with opposite
topological numbers can coexist and have opposite drift directions, two-lane
racetracks can be built in order to accurately encode the data bits. In
addition, the dynamics of bimerons induced by magnetic field gradients and
alternating magnetic fields are investigated. It is found that the bimeron
driven by alternating magnetic fields can propagate along a certain direction.
Moreover, combining a suitable magnetic field gradient, the
Magnus-force-induced transverse motion can be completely suppressed, which
implies that there is no skyrmion Hall effect. Our results are useful for
understanding of the bimeron dynamics and may provide guidelines for building
future bimeron-based spintronic devices.
