Surpassing the Carnot efficiency by extracting imperfect work
A suitable way of quantifying work for microscopic quantum systems has been constantly debated in the field of quantum thermodynamics. One natural approach is to measure the average increase in energy of an ancillary system, called the battery, after a work extraction protocol. The quality of energy...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2017-01-01
|
| Series: | New Journal of Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1367-2630/aa8ced |
| _version_ | 1827873280524025856 |
|---|---|
| author | Nelly Huei Ying Ng Mischa Prebin Woods Stephanie Wehner |
| author_facet | Nelly Huei Ying Ng Mischa Prebin Woods Stephanie Wehner |
| author_sort | Nelly Huei Ying Ng |
| collection | DOAJ |
| description | A suitable way of quantifying work for microscopic quantum systems has been constantly debated in the field of quantum thermodynamics. One natural approach is to measure the average increase in energy of an ancillary system, called the battery, after a work extraction protocol. The quality of energy extracted is usually argued to be good by quantifying higher moments of the energy distribution, or by restricting the amount of entropy to be low. This limits the amount of heat contribution to the energy extracted, but does not completely prevent it. We show that the definition of ‘work’ is crucial. If one allows for a definition of work that tolerates a non-negligible entropy increase in the battery, then a small scale heat engine can possibly exceed the Carnot efficiency. This can be done without using any additional resources such as coherence or correlations, and furthermore can be achieved even when one of the heat baths is finite in size. |
| first_indexed | 2024-03-12T16:35:02Z |
| format | Article |
| id | doaj.art-fd64d759e06141529adbb614971e5003 |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:35:02Z |
| publishDate | 2017-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-fd64d759e06141529adbb614971e50032023-08-08T14:57:07ZengIOP PublishingNew Journal of Physics1367-26302017-01-01191111300510.1088/1367-2630/aa8cedSurpassing the Carnot efficiency by extracting imperfect workNelly Huei Ying Ng0Mischa Prebin Woods1Stephanie Wehner2QuTech, Delft University of Technology , Lorentzweg 1, 2628 CJ Delft, The Netherlands; Centre for Quantum Technologies, National University of Singapore , 3 Science Drive 2, 117543, SingaporeQuTech, Delft University of Technology , Lorentzweg 1, 2628 CJ Delft, The Netherlands; University College of London , Department of Physics & Astronomy, London WC1E 6BT, United KingdomQuTech, Delft University of Technology , Lorentzweg 1, 2628 CJ Delft, The Netherlands; Centre for Quantum Technologies, National University of Singapore , 3 Science Drive 2, 117543, SingaporeA suitable way of quantifying work for microscopic quantum systems has been constantly debated in the field of quantum thermodynamics. One natural approach is to measure the average increase in energy of an ancillary system, called the battery, after a work extraction protocol. The quality of energy extracted is usually argued to be good by quantifying higher moments of the energy distribution, or by restricting the amount of entropy to be low. This limits the amount of heat contribution to the energy extracted, but does not completely prevent it. We show that the definition of ‘work’ is crucial. If one allows for a definition of work that tolerates a non-negligible entropy increase in the battery, then a small scale heat engine can possibly exceed the Carnot efficiency. This can be done without using any additional resources such as coherence or correlations, and furthermore can be achieved even when one of the heat baths is finite in size.https://doi.org/10.1088/1367-2630/aa8cedquantum thermodynamicssingle-shot work extractionquantum heat enginesthermodynamic resource theories |
| spellingShingle | Nelly Huei Ying Ng Mischa Prebin Woods Stephanie Wehner Surpassing the Carnot efficiency by extracting imperfect work New Journal of Physics quantum thermodynamics single-shot work extraction quantum heat engines thermodynamic resource theories |
| title | Surpassing the Carnot efficiency by extracting imperfect work |
| title_full | Surpassing the Carnot efficiency by extracting imperfect work |
| title_fullStr | Surpassing the Carnot efficiency by extracting imperfect work |
| title_full_unstemmed | Surpassing the Carnot efficiency by extracting imperfect work |
| title_short | Surpassing the Carnot efficiency by extracting imperfect work |
| title_sort | surpassing the carnot efficiency by extracting imperfect work |
| topic | quantum thermodynamics single-shot work extraction quantum heat engines thermodynamic resource theories |
| url | https://doi.org/10.1088/1367-2630/aa8ced |
| work_keys_str_mv | AT nellyhueiyingng surpassingthecarnotefficiencybyextractingimperfectwork AT mischaprebinwoods surpassingthecarnotefficiencybyextractingimperfectwork AT stephaniewehner surpassingthecarnotefficiencybyextractingimperfectwork |