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An electrical probe of the phonon mean-free path spectrum.

ABSTRACT: 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.

SUBMITTER: Ramu AT

PROVIDER: S-EPMC5039410 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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An electrical probe of the phonon mean-free path spectrum.

Ramu Ashok T AT Halaszynski Nicole I NI Peters Jonathan D JD Meinhart Carl D CD Bowers John E JE

Scientific reports 20160928

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 arr ...[more]

PMID: 27677238

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