Bipolar Thermoelectricity in Bilayer-Graphene--Superconductor Tunnel Junctions

Abstract

We investigate the thermoelectric properties of a hybrid nanodevice composed by a 2D carbon based material and a superconductor. This system presents nonlinear bipolar thermoelectricity as induced by the spontaneous breaking of the Particle-Hole (PH) symmetry in a tunnel junction between a BiLayer Graphene (BLG) and a Bardeen-Cooper-Schrieffer (BCS) superconductor. In this scheme, the nonlinear thermoelectric effect, predicted and observed in SIS' junctions is not affected by the competitive effect of the Josephson coupling. From a fundamental perspective, the most intriguing feature of this effect is its bipolarity. The capability to open and control the BLG gap guarantees improved thermoelectric performances, that reach up to 1 mV/K regarding the Seebeck coefficient and a power density of 1 nW/$\mu$m${}^2$ for temperature gradients of tens of Kelvins. Furthermore, the externally controlled gating can also dope the BLG, which is otherwise intrinsically PH symmetric, giving us the opportunity to investigate the bipolar thermoelectricity even in presence of a controlled suppression of the PH symmetry. The predicted robustness of this system could foster further experimental investigations and applications in the near future, thanks to the available techniques of nano-fabrication.

References in corpus (21)

• The electronic properties of graphene
• Graphene photodetectors for high-speed optical communications
• Gate-induced insulating state in bilayer graphene devices
• Asymmetry gap in the electronic band structure of bilayer graphene
• The electronic properties of bilayer graphene
• Atomically thin boron nitride: a tunnelling barrier for graphene devices
• Energy gap tuning in graphene on hexagonal boron nitride bilayer system
• Electron-phonon heat transfer in monolayer and bilayer graphene
• Nonlocal Thermoelectric Effects and Nonlocal Onsager Relations in a Three-Terminal Proximity-Coupled Superconductor-Ferromagnet Device
• Radiation effects on the electronic structure of bilayer graphene
• Transport spectroscopy of ultraclean tunable band gaps in bilayer graphene
• Bipolar Thermoelectric Josephson Engine
• Quantitative measurements of the thermal resistance of Andreev interferometers
• Thermopower and thermal conductance of a superconducting quantum point contact
• Nonlocal quantum heat engines made of hybrid superconducting devices
• Superconducting contacts to a monolayer semiconductor
• Large thermoelectric effect in ballistic Andreev interferometers
• Phase-control of bipolar thermoelectricity in Josephson tunnel junctions
• Noise effects in the nonlinear thermoelectricity of a Josephson junction
• Temperature-biased double-loop Josephson flux transducer
• Enhancement in tunneling density of states in Luttinger liquid -- role of non-local interaction

Cited by in corpus (7)

• Hybrid normal-superconducting Aharonov-Bohm quantum thermal device
• A highly-sensitive broadband superconducting thermoelectric single-photon detector
• Thermoelectric processes of quantum normal-superconductor interfaces
• Bipolar thermoelectrical SQUIPT (BTSQUIPT)
• Effect of screening on Seebeck coefficient in bilayer graphene/AlGaAs electron gas
• Bipolar thermoelectric superconducting single-electron transistor
• Quantum coherent control of linear and nonlinear thermoelectricity on graphene nanostructure heat engines