The design of any system of quantum logic must take into account the implications of the Landauer limit for logical bits. Useful computation implies a deterministic outcome, and so any system of quantum computation must produce a final deterministic outcome, which in a quantum computer requires a quantum decision that produces a deterministic qubit. All information is physical, and any bit of information can be considered to exist in a physicality represented as a decision between the two wells of a double well potential in which the energy barrier between the two wells must be greater than kT·ln2. Any proposed system of quantum computation that does not result in such a deterministic outcome can only be considered stochastically as a probability distribution (i.e. a wave function). An example of such determinism in a quantum logic system is theorized to exist in the DNA molecule, where the decoherence of quantum decision results in an enantiomeric shift in the deoxyribose moiety that is appropriate to the Landauer limit.
F. Matthew Mihelic "Implications of the Landauer limit for quantum logic", Proc. SPIE 9123, Quantum Information and Computation XII, 91230B (22 May 2014); https://doi.org/10.1117/12.2048531
Publication date: May 2014, Proceedings Volume 9123, Quantum Information and Computation XII; 91230B (2014) https://doi.org/10.1117/12.2048531 Event: SPIE Sensing Technology + Applications, 2014, Baltimore, Maryland, United States