# Electronic Transport and Thermopower in 2D and 3D Heterostructures--A Theory Perspective

## TL;DR

This review summarizes recent theoretical and experimental advances in understanding electronic and thermoelectric transport in 2D and 3D heterostructures, highlighting progress in simulation techniques and device applications.

## Contribution

It provides a comprehensive overview of recent progress in modeling and understanding transport phenomena in heterostructures, emphasizing new theoretical approaches and their implications for device development.

## Key findings

- Progress in understanding electronic transport in 2D materials and heterojunctions.
- Advances in quantum transport simulation techniques like NEGF and Wigner functions.
- Potential for improved energy harvesting and quantum electronic devices.

## Abstract

In this review, we discuss the impact of interfaces and heterojuctions on the electronic and thermoelectric transport properties of materials. We review recent progress in understanding electronic transport in two-dimensional (2D) materials ranging from graphene to transition metal dichalcogenides (TMDs), their homojunctions (grain boundaries), lateral heterojunctions (such as graphene/MoS$_2$ lateral interfaces), and vertical van der Waals (vdW) heterostructures. We also review work in thermoelectric properties of 2D heterojunctions, as well as their applications in creating devices such as resonant tunneling diodes (RTDs). Lastly, we turn our focus to work in three-dimensional (3D) heterostructures. While transport in 3D heterostructures has been researched for several decades, here we review recent progress in theory and simulation of quantum effects on transport via the Wigner and non-equilibrium Green's functions (NEGF) approaches. These simulation techniques have been successfully applied toward understanding the impact of heterojunctions on the thermoelectric properties, with applications in energy harvesting, and electron resonant tunneling, with applications in RTDs. We conclude that tremendous progress has been made in both simulation and experiments toward the goal of understanding transport in heterostructures and this progress will soon be parlayed into improved energy converters and quantum nanoelectronic devices.