Quantum interference devices and field‐effect transistors: A switch energy comparison

We compare quantum interference devices, exemplified by a resonant tunnel transistor, an Aharonov–Bohm interferometer, and a Y‐branch switch, to field‐effect transistors regarding their capability to reach fundamentally limited switch energies as well as their normalized transconductance. The resonant tunnel transistor is found to behave similarly to the field‐effect transistor (FET). The Aharonov–Bohm interferometer is essentially equivalent to a single‐mode Y‐branch switch, while the Y branch has an advantage in allowing multimode operation. The normalized transconductance of these two devices can be an order of magnitude larger than for a FET.