Artículos de revistas
Low-dimensional thermoelectricity in graphene: The case of gated graphene superlattices
Fecha
2018-07Autor
Molina Valdovinos, Sergio
Martínez Rivera, Freddyson J.
Moreno Cabrera, Nadia E.
Rodríguez Vargas, Isaac
Institución
Resumen
Low-dimensional thermoelectricity is a key concept in modern thermoelectricity. This concept refers to the
possibility to improve thermoelectric performance through redistribution of the density of states by reducing
the dimensionality of thermoelectric devices. Among the most successful low-dimensional structures we can
find superlattices of quantum wells, wires and dots. In this work, we show that this concept can be extended
to cutting-edge materials like graphene. In specific, we carry out a systematic assessment of the thermoelectric
properties of quantum well gated graphene superlattices. In particular, we find giant values for the Seebeck
coefficient and the power factor by redistributing the density of states through the modulation of the fundamental
parameters of the graphene superlattice. Even more important, these giant values can be further improved by
choosing appropriately the angle of incidence of Dirac electrons, the number of superlattice periods, the width
of the superlattice unit cell as well as the height of the barriers. We also find that the power factor presents a
series of giant peaks, clustered in twin fashion, associated to the oscillating nature of the conductance. Finally,
we consider that low-dimensional thermoelectricity in graphene and related 2D materials is promising and
constitutes a possible route to push forward this exciting field.