The influence of vertical vibration on nanoscale friction: A molecular dynamics simulation study

The influence of vibration on friction at the nanoscale was studied via molecular dynamics (MD) simulations. The results show that average friction increases in a high-frequency range. This can be attributed to the vibration of the tip following vibration excitation, which results in peaks of repulsive interaction between tip and substrate and leads to higher friction. However, when the frequency is lower than a certain value, friction decreases. This is because vibration excitation results not in an obvious vibration of the tip but in a slightly larger interface distance, which leads to a decrease in friction.