  We propose a new architecture for implementing electronic interferometry in
quantum Hall bars. It exploits scattering among parallel edge channels. In
contrast to previous developments, this one employs a simply-connected mesa
admitting serial concatenation of building elements closer to optical
analogues. Implementations of Mach-Zehnder and Hambury-Brown-Twiss
interferometers are discussed together with new structures yet unexplored in
quantum electronics.
