{"id":"67f5bd3e-1136-4b55-9a56-117f1ab135b6","arxiv_id":"2605.24554","paper_version":1,"verdict":"UNVERDICTED","confidence":"LOW","novelty_score":4.0,"correctness_risk":"unknown","formal_verification":"none","parameter_count":0,"one_line_summary":"Nonreciprocity modulates inter-dot information flow in a quantum dot information engine and maps to an effective reciprocal system via reparameterized chemical potentials.","lead":"The paper examines a double-quantum-dot setup where nonreciprocal couplings between dots and reservoirs modulate information flow in an autonomous quantum information engine. A smart generalist might read it to see how asymmetry in couplings could serve as a design knob for nanoscale energy-information devices.","discovery_kind":"new_application","skeptic_critique":{"model":"grok-4.3","headline":"Validity of second-law extension to nonreciprocal reservoir couplings and consequent mapping","rationale":"The reader's weakest assumption directly identifies the same point that must be true for the mapping and control-mechanism claims to follow. With the full text now available the concern remains the same; no stronger internal inconsistency appears from the abstract-level description.","tokens_in":1731,"tokens_out":321,"duration_ms":13990,"concrete_test":"Extract the master equation and the claimed entropy-production formula from the methods or supplementary sections; substitute the reparameterized chemical potentials and coupling into the nonreciprocal rates and verify whether the entropy production is identical to the reciprocal case (within numerical tolerance of 1e-10). If the expressions differ by a term linear in the nonreciprocity strength, the mapping does not hold.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim rests on an extension of the second law that incorporates nonreciprocal dot-reservoir couplings, which is then used to justify an exact mapping to an effective reciprocal system by reparameterizing chemical potentials and the inter-dot Coulomb strength. For the mapping to preserve information flow and thermodynamic performance, the modified entropy-production expression must remain non-negative and reduce identically under the reparameterization; any hidden assumption about local detailed balance or the form of the transition rates could invalidate this equivalence. The abstract states the extension is performed, but the load-bearing step is whether the derivation in the full text actually yields a consistent thermodynamic potential without additional constraints on the nonreciprocity parameters.","agreement_with_reader":"agree"},"referee_report":{"model":"grok-4.3","summary":"The manuscript studies an autonomous quantum-dot information engine consisting of an upstream controller dot (coupled to one reservoir) and a downstream working-substance dot (coupled to two reservoirs). By extending the second law to nonreciprocal dot-reservoir couplings, the authors claim that nonreciprocity modulates inter-dot information flow and that the nonreciprocal dynamics are exactly equivalent to those of a reciprocal system after a reparameterization of the chemical potentials and the inter-dot Coulomb interaction. They further examine how nonreciprocity affects engine performance and the range of operating regimes.","tokens_in":1849,"tokens_out":471,"duration_ms":23113,"significance":"If the claimed extension of the second law is rigorously justified and the mapping preserves both information flow and thermodynamic quantities without additional constraints, the work would identify nonreciprocal coupling as a tunable control parameter that can outperform conventional reciprocal designs. The mapping itself would be a useful reduction if shown to hold identically.","major_comments":[{"comment":"The extension of the second law (the section deriving the modified entropy-production expression) must demonstrate that the non-negativity condition continues to hold for arbitrary nonreciprocity parameters without imposing extra constraints on the transition rates; the abstract states the extension is performed, but the load-bearing step is whether the derivation yields a consistent thermodynamic potential that reduces identically under the reparameterization.","section":"Section deriving the extended second law"},{"comment":"The mapping to an effective reciprocal system (the section presenting the reparameterization of chemical potentials and electron-electron coupling) must be shown to leave the information-flow term and the entropy-production expression invariant; any implicit assumption about local detailed balance or the functional form of the rates would invalidate the claimed equivalence.","section":"Section on the mapping to effective reciprocal system"}],"minor_comments":[{"comment":"Notation for the nonreciprocity parameters should be introduced with an explicit definition before being used in the thermodynamic relations.","section":null},{"comment":"Figure captions should state whether the plotted quantities are obtained analytically or numerically and which parameter values are held fixed.","section":null}],"recommendation":"major_revision","confidential_remarks":null},"author_rebuttal":{"model":"grok-4.3","summary":"We thank the referee for their thorough review and valuable comments, which help clarify the presentation of our results. Below we respond point-by-point to the major comments. We will revise the manuscript to strengthen the explicit demonstrations requested.","responses":[{"response":"The entropy-production expression is obtained directly from the standard Markovian form Σ = Σ_{i,j} W_{ij} p_j ln(W_{ij} p_j / W_{ji} p_i), which is nonnegative for any choice of rates W_{ij} (including nonreciprocal dot-reservoir couplings) by the properties of the logarithm; no additional constraints on the rates are imposed beyond those already required for a valid master equation. The thermodynamic potential is constructed from the same rates and chemical potentials, so that under the reparameterization it reduces identically by algebraic substitution. To make this fully explicit we will add a short subsection that (i) states the non-negativity proof for arbitrary nonreciprocity and (ii) verifies the identical reduction of the potential.","revision_made":"yes","referee_comment":"[Section deriving the extended second law] The extension of the second law (the section deriving the modified entropy-production expression) must demonstrate that the non-negativity condition continues to hold for arbitrary nonreciprocity parameters without imposing extra constraints on the transition rates; the abstract states the extension is performed, but the load-bearing step is whether the derivation yields a consistent thermodynamic potential that reduces identically under the reparameterization."},{"response":"The reparameterization is defined so that the steady-state occupation probabilities, the inter-dot transition rates, and therefore the information-flow term (mutual-information rate) are numerically identical in the original and mapped systems. Because the rates continue to satisfy local detailed balance with respect to the reparameterized reservoir chemical potentials, the entropy-production expression is likewise invariant by direct substitution. We will insert an explicit verification (in the main text or a short appendix) that both the information-flow term and the full entropy-production expression remain unchanged under the mapping, without invoking any special functional form beyond the standard Fermi-Dirac rates used throughout the paper.","revision_made":"yes","referee_comment":"[Section on the mapping to effective reciprocal system] The mapping to an effective reciprocal system (the section presenting the reparameterization of chemical potentials and electron-electron coupling) must be shown to leave the information-flow term and the entropy-production expression invariant; any implicit assumption about local detailed balance or the functional form of the rates would invalidate the claimed equivalence."}],"tokens_in":1372,"tokens_out":553,"duration_ms":23929,"standing_objections":[]},"desk_editor":{"model":"grok-4.3","letter":"Nonreciprocity in this double quantum dot setup can be reparameterized away into an effective reciprocal system, giving a handle on information flow without changing the underlying physics much.\n\nThe authors build an autonomous information engine with an upstream controller dot coupled to one reservoir and a downstream working dot coupled to two. They extend the second law to include nonreciprocal dot-reservoir couplings and use that to show how nonreciprocity alters the inter-dot information flow and the engine's thermodynamic performance. The mapping to reciprocal parameters for chemical potentials and Coulomb strength is the main technical step.\n\nThis approach is new in applying nonreciprocity specifically to information flow control in quantum dots. It does well in identifying a practical control parameter that could be tuned in experiments, and in analyzing the resulting changes to efficiency and operation regimes.\n\nThe potential issue is whether the extended second law derivation actually supports an exact mapping. The concern is that the entropy production might not reduce identically if the nonreciprocal rates don't satisfy the same detailed balance conditions as reciprocal ones. Without seeing the explicit master equation or the proof that the reparameterized system reproduces the same currents and information measures, it's difficult to judge if the equivalence is rigorous or if it requires extra constraints.\n\nThe paper stays within the standard framework of quantum thermodynamics for open systems, so the thinking looks honest even if the central step needs more detail.\n\nThis paper is for specialists in quantum information engines and non-equilibrium thermodynamics. Someone working on similar dot systems would find the control mechanism worth checking.\n\nIt should go to peer review so referees can examine the derivations and see if the mapping holds up under the full equations.","headline":"Nonreciprocity maps to an effective reciprocal system via chemical potential and coupling reparameterization, giving a control handle on information flow, but the second-law extension needs explicit checks in the derivations.","tokens_in":2310,"tokens_out":422,"would_cite":false,"duration_ms":27769,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"grok-4.3","headline":"Nonreciprocity modulates inter-dot information flow in a double-quantum-dot engine and maps to an equivalent reciprocal system via reparameterization.","keywords":["nonreciprocal couplings","quantum dot information engines","inter-dot information flow","thermodynamic performance","second law extension","effective reciprocal mapping","quantum thermodynamics","electron-electron coupling"],"falsifier":"A direct computation of steady-state information currents in the nonreciprocal setup that fails to match the currents obtained from the reparameterized reciprocal system after adjusting chemical potentials and coupling strength.","tokens_in":2612,"feed_emoji":"","tokens_out":604,"duration_ms":24805,"temperature":0.7,"pith_summary":"The paper examines an autonomous information engine consisting of a downstream quantum dot acting as the working substance coupled to two reservoirs and an upstream dot acting as the controller coupled to a single reservoir. By extending the second law of thermodynamics to account for nonreciprocal couplings, the authors show that nonreciprocity significantly modulates the information flow between the dots and thereby supplies a control mechanism. They further establish that this influence is equivalent to that of a reciprocal system after a reparameterization of chemical potentials and the electron-electron coupling strength. The framework also tracks how nonreciprocity alters the engine's thermodynamic performance and operating regime.","feed_headline":"Nonreciprocity maps to reciprocal system in quantum dot engines","feed_subtitle":"Reparameterization of chemical potentials and coupling strength controls information flow and engine performance.","key_machinery":"Mapping of the nonreciprocal double-dot system to an effective reciprocal system by reparameterizing chemical potentials and electron-electron coupling strength.","core_discovery":"By extending the second law of thermodynamics to incorporate the effects of nonreciprocal couplings between the dots and their electronic reservoirs, we develop a thermodynamic framework that allows us to demonstrate that nonreciprocity can significantly modulate the inter-dot information flow, thereby providing a robust control mechanism. We show that the influence of nonreciprocity can be equivalently understood through a mapping to an effective reciprocal system upon a reparameterization of chemical potentials and the electron-electron coupling strength. We further analyze the impact of nonreciprocity on the engine's performance and operation regime.","pith_inferences":["The reparameterization technique could be tested by comparing measured currents across a range of coupling asymmetries in fabricated double-dot devices.","Similar mappings might apply to other autonomous quantum engines that incorporate nonreciprocal reservoir couplings.","The control offered by nonreciprocity could be combined with gate-voltage tuning to achieve finer performance adjustments."],"forward_implications":["Nonreciprocity supplies a robust control mechanism for inter-dot information flow.","The engine performance and operation regime can be modulated beyond what reciprocal configurations allow.","The mapping simplifies analysis by reducing the nonreciprocal case to an equivalent reciprocal problem.","Nonreciprocal coupling functions as an effective design knob for optimizing quantum dot information engines."],"fun_headline_variants":["Nonreciprocity controls info flow in quantum dot engines","Nonreciprocal dots map to reciprocal systems via reparameterization","Nonreciprocity modulates inter-dot flow through chemical potential shifts","Thermodynamic framework shows nonreciprocity in quantum dot engines"],"cache_read_input_tokens":2112,"weakest_assumption_plain":"The extension of the second law of thermodynamics to nonreciprocal couplings between the dots and their electronic reservoirs is valid and permits the claimed mapping to an effective reciprocal system.","fun_headline_variants_meta":{"raw":{"variants":["Nonreciprocity controls info flow in quantum dot engines","Nonreciprocal dots map to reciprocal systems via reparameterization","Nonreciprocity modulates inter-dot flow through chemical potential shifts","Thermodynamic framework shows nonreciprocity in quantum dot engines"]},"model":"grok-4.3","cost_usd":0.004111,"raw_usage":{"total_tokens":2096,"prompt_tokens":688,"num_sources_used":0,"completion_tokens":63,"cost_in_usd_ticks":41112000,"prompt_tokens_details":{"text_tokens":688,"audio_tokens":0,"image_tokens":0,"cached_tokens":256},"completion_tokens_details":{"audio_tokens":0,"reasoning_tokens":1345,"accepted_prediction_tokens":0,"rejected_prediction_tokens":0}},"tokens_in":688,"tokens_out":63,"duration_ms":12590,"temperature":1.0,"reasoning_tokens":1345,"cache_read_input_tokens":256,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-06-30T12:07:29.589559+00:00","model_set":{"reader":"grok-4.3"},"falsifier":"A direct computation of steady-state information currents in the nonreciprocal setup that fails to match the currents obtained from the reparameterized reciprocal system after adjusting chemical potentials and coupling strength.","supporting_citations":[],"review_version":1}