Comment on "Entropic Costs of Extracting Classical Ticks from a Quantum Clock"

• URL: http://arxiv.org/abs/2605.21833v1
• Date: Wed, 20 May 2026 23:53:01 GMT
• Title: Comment on "Entropic Costs of Extracting Classical Ticks from a Quantum Clock"
• Abstract summary: A recent Letter by Wadhia et al. reports a realization of a quantum clock using a double quantum dot (DQD)<n>This Comment identifies two fundamental issues: (I) the claimed quantum clock" exhibits only classical behavior and lacks intrinsic temporal correlations between ticks; it is not sufficient for accurate time as a good clock.
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• License: http://creativecommons.org/licenses/by-nc-sa/4.0/
• Abstract: A recent Letter by Wadhia et al. reports a realization of a quantum clock using a double quantum dot (DQD) [Phys. Rev. Lett. 135, 200407 (2005)]. This Comment identifies two fundamental issues: (I) the claimed ``quantum clock" exhibits only classical behavior and lacks intrinsic temporal correlations between ticks; it is not sufficient for accurate time as a good clock. (II) the thermodynamic analysis misassigns entropy production and conflates amplification with measurement; the reported combined entropy is an engineering dissipation, not a fundamental cost of quantum timekeeping.

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