Lattice thermal conductivity of wires

The lattice thermal conductivity of free standing wires is calculated withi n a Boltzmann equation approach. Diffusive and specular phonon scattering a t the wire surfaces are included by appropriate boundary conditions on the phonon distribution. The wire thermal conductivity is found to decrease mar kedly below the bulk value for narrow wires. We show that this decrease in wires is larger than that which occurs in free standing wells of comparable size. (C) 1999 American Institute of Physics. [S0021-8979(99)07105-4].