Beating Carnot efficiency with periodically driven chiral conductors
Ryu, Sungguen; López, Rosa; Serra, Llorenç; Sanchez, David
Nature Communications 13, 2512 (2022)
Nature Communications 13, 2512 (2022)
Classically, the power generated by an ideal thermal machine cannot be larger than the Carnot limit. This profound result is rooted in the second law of thermodynamics. A hot question is whether this bound is still valid for microengines operating far from equilibrium. Here, we demonstrate that a quantum chiral conductor driven by AC voltage can indeed work with efficiencies much larger than the Carnot bound. The system also extracts work from common temperature baths, violating Kelvin-Planck statement. Nonetheless, with the proper definition, entropy production is always positive and the second law is preserved. The crucial ingredients to obtain efficiencies beyond the Carnot limit are: i) irreversible entropy production by the photoassisted excitation processes due to the AC field and ii) absence of power injection thanks to chirality. Our results are relevant in view of recent developments that use small conductors to test the fundamental limits of thermodynamic engines.
Related research projects
MACTOPE
MATERIA CUANTICA TOPOLÓGICA: PRECISIÓN Y ENERGÍA
I.P.: Rosa Lopez
In the last two decades we have witnessed an unprecedented revolution with the progress of new technologies based on the properties of so-called quantum matter. Examples are quantum computing that uses quantum …
QuTTNAQMa
TRANSPORTE CUANTICO Y TERMODINAMICA: NUEVAS AVENIDAS EN MATERIALES CUANTICOS
I.P.: Rosa Lopez, Llorenç Serra
The aim of this project is to investigate the heat and energy transport properties in nanoconductors considering complex phenomena due to either many-body interactions and/or the presence of quantum materials.
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