Experimental realization of a Fabry-Perot-type interferometer by copropagating edge states in the quantum Hall regime

A Fabry-Perot-type interferometer is experimentally realized for electrons in a semiconductor device. A special experimental geometry creates interference conditions for copropagating electrons in quantum Hall edge states, which results in oscillations of the current through the device. The visibility of these oscillations is found to increase at the high-field edge of the quantum Hall plateau.