  We investigated the time dependence of two-electron spin states in a double
quantum dot fabricated in an InAs nanowire. In this system, spin-orbit
interaction has substantial influence on the spin states of confined electrons.
Pumping single electrons through a Pauli spin-blockade configuration allowed to
probe the dynamics of the two coupled spins via their influence on the pumped
current. We observed spin-relaxation with a magnetic field dependence different
from GaAs dots, which can be explained by spin-orbit interaction. Oscillations
were detected for times shorter than the relaxation time, which we attribute to
coherent evolution of the spin states.
