Although the thermal properties of millimeter-sized carbon nanotube mats and packed carbon nanofibers have been readily measured, measurements for a single nanotube are extremely difficult. Here, we report a novel method that can reliably measure the thermal conductivity of a single carbon nanotube using a suspended sample-attached T-type nanosensor. Our experimental results show that the thermal conductivity of a carbon nanotube at room temperature increases as its diameter decreases, and exceeds 2000 W/mK for a diameter of 9.8 nm. The temperature dependence of the thermal conductivity for a carbon nanotube with a diameter of 16.1 nm appears to have an asymptote near 320 K. The present method is, in principle, applicable to any kind of a single nanofiber, nanowire, and even single-walled carbon nanotube.

In recent years, several researchers have reported the occurrence of reversible resistance switching effects in simple metal nanogap junctions. A large negative resistance is observed in the I-V characteristics of such a junction when high-bias voltages are applied. This phenomenon is characteristic behaviour on the nanometre scale; it only occurs for gap widths slightly under 13 nm. Furthermore, such a junction exhibits a non-volatile resistance hysteresis when the bias voltage is reduced very rapidly from a high level to around 0 V, and when the bias voltage is reduced slowly. This non-volatile resistance change occurs as a result of changes in the gap width between the metal electrodes, brought about by the applied bias voltage.

This letter reports on the measurements of the in-plane thermal conductivity and the electrical conductivity of a microfabricated, suspended, nanosized platinum thin film with the width of 260nm, the thickness of 28nm, and the length of 5.3μm. The experimental results show that the electrical conductivity, the resistance-temperature coefficient and the in-plane thermal conductivity of the nanofilm are greatly lower than the corresponding bulk values from 77to330K. The comparison results indicate that the relation between the thermal conductivity and the electrical conductivity of this nanofilm might not follow the Wiedemann–Franz law that describes the relation between the thermal conductivity and the electrical conductivity of a bulk metallic material.

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The dielectric properties of (Pb,-,X,)(Zr,,Ti,,)03 (X = Ca, Sr, Ba) ceramics (abbreviated PXZT) were investigated for applications to multilayer ceramic capacitors (MLCs) with dielectric layers thinner than 10 pm. The dissipation factors for MLCs with 5-pm-thick dielectric layers were estimated from those for 100-pm-thick disk specimens measured at an oscillation voltage of 20 V,,,,,. Those for PCZT and PSZT were less than 1.0% when the oscillation voltage was 20 V,,,, while those for conventional BaTi0,-based dielectric ceramics were greater than 2.5% at 20 V,.,,. According to polarization-electric field hysteresis measurements, PCZT and PSZT revealed linear and double hysteresis loops, respectively, while PBZT and BaTiO, indicated typical ferroelectric hysteresis loops. The differences in the dissipation factors for the dielectric compositions are attributed to hysteresis in the polarization-electric field loops. These results suggest that PCZT and PSZT are promising dielectric ceramics for MLCs with dielectric layers thinner than 10 ym.