A Berkeley-led study in 2016 by S. Lee et al. also found a large violation of the Wiedemann–Franz law near the insulator-metal transition in VO 2 nanobeams. In the metallic phase, the electronic contribution to thermal conductivity was much smaller than what would be expected from the Wiedemann–Franz law. The results can be explained in terms of independent propagation of charge and heat in a strongly correlated system.