The Second Law in Quantum Pure State Thermodynamics: Making Heat Flow from Cold to Hot & Other Interesting Things
| dc.contributor.advisor | Kellman, Michael | |
| dc.contributor.author | Lotshaw, Phillip | |
| dc.date.accessioned | 2020-09-24T17:13:41Z | |
| dc.date.available | 2020-09-24T17:13:41Z | |
| dc.date.issued | 2020-09-24 | |
| dc.description.abstract | Recent theoretical and experimental work on the foundations of statistical mechanics and thermodynamics has shown that quantum pure states typically evolve to thermal equilibrium. We focus on formulating the second law of thermodynamics for these states. The standard quantum von Neumann quantum entropy is constant during equilibration, S^{vN}=0, in apparent conflict with the entropy increase of the second law, ΔS_{univ} > 0. We explore a recently developed entropy S_{univ}^Q for a pure state and test its behavior in simulations of a model system and environment evolving in time with heat flow to equilibrium. We find that the entropy approaches the correct classical value in a type of classical limit with weak coupling. With stronger coupling, we find a new source of quantum "excess entropy production," which has its origin in the quantum spreading of the wavepacket. Are there quantum thermodynamic effects related to this new source of entropy? To test this, we developed a model for a small variable temperature quantum oscillator bath. We performed simulations where two small baths are linked by a system, with unequal couplings to the baths. The model evolves to a novel type of equilibrium state with unequal temperatures in the baths, with heat flow from cold to hot along the path to equilibrium. We give an account of this behavior in terms of the second law with the quantum entropy S_{univ}^Q. The new formulation of the second law thus appears well-founded and fruitful, with surprising new quantum thermodynamic effects that may still be awaiting discovery, for example in molecules or systems far from equilibrium. This dissertation includes previously published and unpublished co-authored material. | en_US |
| dc.identifier.uri | https://hdl.handle.net/1794/25620 | |
| dc.language.iso | en_US | |
| dc.publisher | University of Oregon | |
| dc.rights | All Rights Reserved. | |
| dc.subject | entropy | en_US |
| dc.subject | heat | en_US |
| dc.subject | quantum thermodynamics | en_US |
| dc.subject | second law | en_US |
| dc.subject | statistical mechanics | en_US |
| dc.subject | temperature | en_US |
| dc.title | The Second Law in Quantum Pure State Thermodynamics: Making Heat Flow from Cold to Hot & Other Interesting Things | |
| dc.type | Electronic Thesis or Dissertation | |
| thesis.degree.discipline | Department of Chemistry and Biochemistry | |
| thesis.degree.grantor | University of Oregon | |
| thesis.degree.level | doctoral | |
| thesis.degree.name | Ph.D. |
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