  Understanding energy dissipation and transport in nanoscale structures is of
great importance for the design of energy-efficient circuits and
energy-conversion systems. This is also a rich domain for fundamental
discoveries at the intersection of electron, lattice (phonon), and optical
(photon) interactions. This review presents recent progress in understanding
and manipulation of energy dissipation and transport in nanoscale solid-state
structures. First, the landscape of power usage from nanoscale transistors
(~10^-8 W) to massive data centers (~10^9 W) is surveyed. Then, focus is given
to energy dissipation in nanoscale circuits, silicon transistors, carbon
nanostructures, and semiconductor nanowires. Concepts of steady-state and
transient thermal transport are also reviewed in the context of nanoscale
devices with sub-nanosecond switching times. Finally, recent directions
regarding energy transport are reviewed, including electrical and thermal
conductivity of nanostructures, thermal rectification, and the role of
ubiquitous material interfaces.
