Thermal-electric conversion is crucial for smart energy control and
harvesting, such as thermal sensing and waste heat recovering. So far, people
are aware of only two ways of direct thermal-electric conversion, Seebeck and
pyroelectric effects, each with distinct working conditions and limitations.
Here, we report the third way of thermal-electric conversion beyond Seebeck and
pyroelectric effects. In contrast to Seebeck effect that requires spatial
temperature difference, the-third-way converts the time-dependent ambient
temperature fluctuation into electricity, similar to the behavior of
pyroelectricity. However, the-third-way is also distinct from pyroelectric
effect in the sense that it does not require polar materials but applies to
general conducting systems. We demonstrate that the-third-way results from the
temperature-fluctuation-induced dynamical charge redistribution. It is a
consequence of the fundamental nonequilibrium thermodynamics and has a deep
connection to the topological phase in quantum mechanics. The findings expand
our knowledge and provide new means of thermal-electric energy harvesting.Comment: 4 pages, 3 figure