2012 — Bérut et al. (Nature) — They used a single colloidal silica bead (2 μm) trapped in a double-well potential created by a focused laser. By modulating the potential to erase the bit, they showed that mean dissipated heat saturates at the Landauer bound (k_B T ln 2) in the limit of long erasure cycles.
https://www.physics.rutgers.edu/~morozov/677_f2017/Physics_6...
2014 — Jun et al. (PRL) — A higher-precision follow-up using 200 nm fluorescent particles in an electrokinetic feedback trap. Same basic physics, tighter error bars.
https://pmc.ncbi.nlm.nih.gov/articles/PMC4795654/
2016 — Hong et al. (Science Advances) — First test on actual digital memory hardware. Used arrays of sub-100 nm single-domain Permalloy nanomagnets and measured energy dissipation during adiabatic bit erasure using magneto-optic Kerr effect magnetometry. The measured dissipation was consistent with the Landauer limit within 2 standard deviations using the actual the basis of magnetic storage.
https://www.science.org/doi/10.1126/sciadv.1501492
2018 — Guadenzi et al. (Nature Physics) — Opens with:
The erasure of a bit of information is an irreversible operation whose minimal entropy production of kB ln 2 is set by the Landauer limit1. This limit has been verified in a variety of classical systems, including particles in traps2,3 and nanomagnets4. Here, we extend it to the quantum realm by using a crystal of molecular nanomagnets as a quantum spin memory and showing that its erasure is still governed by the Landauer principle.
https://www.nature.com/articles/s41567-018-0070-7
The Landauer limit is not conjecture.
It's been experimentally demonstrated. Practical or not, the effect is real.
The objection seems to be the "free lunch" assumptions being made about shrinkability.
"What Is TANSTAAFL?" https://youtu.be/ZrZUe7R44eA?si=oK2H1L9ha1zQhDOh
I am pretty ignorant of this field.