Near-Landauer-Bound Quantum Computing Engineering Using Single Spins

Quantum computing engineering integrates quantum electronic engineering and computer science required to develop quantum computer hardware and software. In this study, we used four experiments (a single spin experiment, a giant spin experiment, a nanomagnet experiment, and the Stern–Gerlach experiment) to demonstrate that a single spin was much more energy efficient due to its small size and weak coupling with the surroundings. We conclude that quantum spintronics, with a single spin as a qubit, is a near-Landauer-bound computing engineering. This means that it is approaching the theoretical limit on the minimum amount of energy required to perform a computation, as defined by Landauer's principle. Our study is also the first experimental verification of Landauer's bound on a single spin, which is the smallest information carrier in size.