Effects of Rashba spin–orbit coupling and a magnetic field on a polygonal quantum ring

• Spin conductance of polygon with RSOC and magnetic field is calculated analytically.
• We show how the RSOC and a magnetic field control the phase of electron in polygon.
• The AB oscillation and shape-dependent conductance are studied in a polygonal ring.
• Our model can provide spin filtering simply by interchanging the source and drain.

Using standard quantum network method, we analytically investigate the effect of Rashba spin–orbit coupling (RSOC) and a magnetic field on the spin transport properties of a polygonal quantum ring. Using Landauer–Büttiker formula, we have found that the polarization direction and phase of transmitted electrons can be controlled by both the magnetic field and RSOC. A device to generate a spin-polarized conductance in a polygon with an arbitrary number of sides is discussed. This device would permit precise control of spin and selectively provide spin filtering for either spin up or spin down simply by interchanging the source and drain.