Heat conduction analysis of nano-tip and storage medium in thermal-assisted data storage using molecular dynamics simulation

In the thermal-assisted data storage technologies, the behavior of heat transfer between the nano-tips and the storage medium during thermo-mechanical data bit formation process is a critical factor affecting the areal storage density, data bit writing/reading speed and system reliability. In this paper, the thermal properties of a nano-tip are analyzed using the non-equilibrium molecular dynamics simulation. The simulated results show that the effects of the nano-structural configuration and boundary conditions on the thermal transport are remarkable, which can be attributed to the phonon boundary-scattering and possible phonon spectrum modification. Furthermore, the heat transfer between the nano-tip and the silicon medium film is simulated. The results show that the medium film can be efficiently heated locally with no pressure force. For a tip-medium contact area of 5.31nm², an area of about 95.5 nm² on the medium surface can be heated with a temporal resolution of 0.11 ns. This time period is much smaller than the conduction timescale (≈2 μs) on the nano-tip in the heat-assisted scanning probe-based data storage technology during data bit writing process.