  Variance-based logic (VBL) uses the fluctuations or the variance in the state
of a particle or a physical quantity to represent different logic levels. In
this letter we show that compared to the traditional bi-stable logic
representation the variance-based representation can theoretically achieve a
superior performance trade-off (in terms of energy dissipation and information
capacity) when operating at fundamental limits imposed by thermal-noise. We
show that for a bi-stable logic device the lower limit on energy dissipated per
bit is 4.35KT/bit, whereas under similar operating conditions, a VBL device
could achieve a lower limit of sub-KT/bit. These theoretical results are
general enough to be applicable to different instantiations and variants of VBL
ranging from digital processors based on energy-scavenging or to processors
based on the emerging valleytronic devices.
