  An array of quantum rings with local (ring by ring) modulation of the spin
orbit interaction (SOI) can lead to novel effects in spin state transformation
of electrons. It is shown that already small (3x3, 5x5) networks are remarkably
versatile from this point of view: Working in a given network geometry, the
input current can be directed to any of the output ports, simply by changing
the SOI strengths by external gate voltages. Additionally, the same network
with different SOI strengths can be completely analogous to the Stern-Gerlach
device, exhibiting spatial-spin entanglement.
