Approaching the Landauer limit via nanomechanical resonators

Thesis (Ph.D.)--Boston UniversityPLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.According to the von Neumann-Landauer principle (VNL) for every bit of information lost during a computation, kT ln 2 amount of heat is dissipated into the environment. Irreversible logic, the basis of modern computing, inevitably leads to loss of information and is thus fundamentally bound by the VNL principle. However, its validity has been challenged since its inception and the case concerning its legitimacy is still open. Due to the tiny energy scales involved, this debate has been entirely academic in nature and an experimental test of the VNL principle is highly desired by both proponents and skeptics. Such a test would entail contrasting the energy dissipation of irreversible and reversible logic. In particular, we need to perform a non trivial logic both reversibly and irreversibly based on identical technology, testing whether or not energy dissipation for the reversible computation can be less than VNL limit while the irreversible computation is limited by the VNL limit. Reversible logic does not entail information loss, and hence is not bound by the VNL limit. It offers the potential for indefinite performance improvements of digital electronics. Bennett's Turing machine first proved that any computation can be performed reversibly and, in the proper limit, without energy cost. This promise of computing for free has spurred Fredkin, Toffoli, Wilczek, Feynman and others to propose reversible logic gates, though very few experimentally-realized reversible logic gates have since been reported. Here, we experimentally demonstrate for the first time the core of a logically reversible, CMOS-compatible, scalable nanoelectromechanical Fredkin gate, a universal logic gate from ... [TRUNCATED]2031-01-0