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Updated: Sep 26, 2025
Analysis of Contact Interfaces for Single GaN Nanowire Devices
Published on: November 15, 2013
Thermal Conductivity of GaAs Nanowire Arrays Measured by the 3ω Method
Ara Ghukasyan1, Pedro Oliveira1, Nebile Isik Goktas1
1Department of Engineering Physics, McMaster University, Hamilton, Ontario, ON L8S 4L8, Canada.
Abstract:
Vertical nanowire (NW) arrays are the basis for a variety of nanoscale devices. Understanding heat transport in these devices is an important concern, especially for prospective thermoelectric applications. To facilitate thermal conductivity measurements on as-grown NW arrays, a common NW-composite device architecture was adapted for use with the 3ω method. We describe the application of this technique to obtain thermal conductivity measurements on two GaAs NW arrays featuring ~130 nm diameter NWs with a twinning superlattice (TSL) and a polytypic (zincblende/wurtzite) crystal structure, respectively. Our results indicate NW thermal conductivities of 5.2 ± 1.0 W/m-K and 8.4 ± 1.6 W/m-K in the two samples, respectively, showing a significant reduction in the former, which is the first such measurements on TSL NWs. Nearly an order of magnitude difference from the bulk thermal conductivity (~50 W/m-K) is observed for the TSL NW sample, one of the lowest values measured to date for GaAs NWs.
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