Aspects of metallic low-temperature transport in Mott-insulator/ band-insulator superlattices: optical conductivity and thermoelectricity

Abstract

We investigate the low-temperature electrical and thermal transport properties in atomically precise metallic heterostructures involving strongly-correlated electron systems. The model of the Mott-insulator/ band-insulator superlattice was discussed in the framework of the slave-boson mean-field approximation and transport quantities were derived by use of the Boltzmann transport equation in the relaxation-time approximation. The results for the optical conductivity are in good agreement with recently published experimental data on (LaTiO${}_3{)}_N$/(SrTiO${}_3{)}_M$ superlattices and allow us to estimate the values of key parameters of the model. Furthermore, predictions for the thermoelectric response were made and the dependence of the Seebeck coefficient on model parameters was studied in detail. The width of the Mott-insulating material was identified as the most relevant parameter, in particular, this parameter provides a way to optimize the thermoelectric power factor at low temperatures.

References in corpus (10)

• Polar Discontinuity Doping of the LaVO_3/SrTiO_3 Interface
• Optical Study of the Free Carrier Response of LaTiO3/SrTiO3 Superlattices
• The Mott insulator LaTiO_3 in heterostructures with SrTiO_3 is metallic
• Modulation Doping near Mott-Insulator Heterojunctions
• Slave-boson approach to the metallic stripe phases with large unit cells
• Metallic interface at the boundary between band and Mott insulators
• Effect of charge modulation in (LaVO3)m(SrVO3)n superlattices on the insulator-metal transition
• Strongly renormalized quasi-two-dimensional electron gas in a heterostructure with correlation effects
• Electronic Interface Reconstruction at Polar-Nonpolar Mott Insulator Heterojunctions
• Electronic thermal transport in strongly correlated multilayered nanostructures

Cited by in corpus (5)

• Interaction-induced quantum spin Hall insulator in the organic Dirac electron system $\alpha$-(BEDT-TSeF)${}_2$I${}_3$
• Electronic and magnetic properties in strongly correlated heterostructures
• Spectral changes in layered $f$-electron systems induced by Kondo hole substitution in the boundary-layer
• Electrical permittivity driven metal-insulator transition in heterostructures of nonpolar Mott- and band insulators
• Role of multiple subband renormalization in the electronic transport of correlated oxide superlattices