  We show that the state of a flying qubit may be transferred to a chain of
identical, (near) ferromagnetically polarised, but non-interacting, static
spin-1/2 particles in a passive way. During this process the flying qubit is
coherently polarised, emerging in the direction of the majority static spins.
We also show that this process is reversible for at least two flying qubits
injected sequentially and thus has the potential to be exploited as a passive
quantum memory to encode the flying qubits without the necessity of resetting
between successive encoding operations. We show that the quantum information
may be spread over many static spins in the memory chain, making the mechanism
resistent to spin decoherence and other imperfections. Among some potential
architectures, we discuss implementing the memory in a photonic waveguide
embedded with quantum dots, which is resilient to various possible errors.
