In embodiments of the present invention, a non-blocking quantum interference switch includes a segmented electron wave coupler that splits an electron wave and couples its two parts to two arms of a Mach Zehnder interferometer. A voltage may be applied to an interferometer gate electrode to change the phase of the electron wave traveling in that arm. A second segmented electron wave coupler may receive the two electron waves from the interferometer arms and recombine them into one electron wave. If the two electron waves interfere constructively, then the recombined electron wave exits through one switch output port, which may be a "logical zero" switch port, and if the two electron waves interfere destructively, then the recombined electron wave exits through a second switch output port, which may be a "logical one" switch port.