Nonlinear chiral refrigerators

Abstract

We investigate a mesoscopic refrigerator based on chiral quantum Hall edge channels. We discuss a three-terminal cooling device in which charge transport occurs between a pair of voltage-biased terminals only. The third terminal, which is to be cooled, is set as a voltage probe with vanishing particle flux. This largely prevents the generation of direct Joule heating which ensures a high coefficient of performance. Cooling operation is based on energy-dependent quantum transmissions. The latter are implemented with the aid of two tunable scattering resonances (quantum dots). To find the optimal performance point and the largest temperature difference created with our refrigerator, it is crucial to address the nonlinear regime of transport, accounting for electronelectron interaction effects. Our numerical simulations show that the maximal cooling power can be tuned with the quantum dot couplings and energy levels. Further, we provide analytical expressions within a weakly nonlinear scattering-matrix formalism which allow us to discuss the conditions for optimal cooling in terms of generalized thermopowers. Our results are important for the assessment of chiral conductors as promising candidates for efficient quantum refrigerators with low dissipation.

Thermoelectric cooling properties of a quantum Hall Corbino device

“…A significant amount of work has been published on thermoelectricity in quantum coherent systems. Paradigmatic examples are quantum dots [7][8][9][10][11][12][13][14][15][16], nanowires [17,18] quantum point contacts [19][20][21][22] and topological edge states of the quantum Hall and the quantum spin Hall regimes [23][24][25][26][27][28][29][30][31][32][33][34][35]. In these cases transport takes place through a few ballistic channels.…”

Thermodynamics and Steady State of Quantum Motors and Pumps Far from Equilibrium

“…In recent years, there has been a sustained growth in the interest in different forms of nanomachines. This was boosted by seminal experiments [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ], the blooming of new theoretical proposals [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ], and the latest developments towards the understanding of the fundamental physics underlying such systems [ 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 ]. Quantum mechanics has proven to be crucial in the description of a broad family of nanomachines, which can be put together under the generic name of “quantum motors” and “quantum pumps” [ 13 , 46 , 47 , 48 , 49 , 50 , ...…”

Thermodynamics of a Phase-Driven Proximity Josephson Junction

“…Superconducting hybrid systems, i.e., constituted of superconducting parts in electric contact with normal (non-superconducting) parts, are in practice coherent electron systems with striking thermodynamic equilibrium/transport properties, resulting in a wide variety of applicative devices: low-temperature sensitive thermometers [ 15 , 16 , 17 , 18 , 19 ], sensitive detectors [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ], heat valves [ 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ], caloritronics (heat computing) [ 11 , 37 , 44 , 45 , 46 , 47 , 48 ], solid-state micro-refrigerators [ 18 , 49 , 50 , 51 , 52 , 53 , 54 , 55 ], solid-state quantum machines [ 56 , 57 , 58 , 59 , 60 , 61 ], thermoelectric generators [ 62 ,…”