Most studies of the mean-free path accumulation function (MFPAF) rely on optical techniques to probe heat transfer at length scales on the order of the phonon mean-free path. In this paper, we propose and implement a purely electrical probe of the MFPAF that relies on photo-lithographically defined heater-thermometer separation to set the length scale. An important advantage of the proposed technique is its insensitivity to the thermal interfacial impedance and its compatibility with a large array of temperature-controlled chambers that lack optical ports. Detailed analysis of the experimental data based on the enhanced Fourier law (EFL) demonstrates that heat-carrying phonons in gallium arsenide have a much wider mean-free path spectrum than originally thought.
@article{arxiv.1602.00381,
title = {An electrical probe of the phonon mean-free path spectrum},
author = {Ashok T. Ramu and Nicole I. Halaszynski and Jonathan D. Peters and Carl D. Meinhart and John E. Bowers},
journal= {arXiv preprint arXiv:1602.00381},
year = {2016}
}