Parametric strong mode-coupling in carbon nanotube mechanical resonators

Shu-Xiao Li, Dong Zhu, Xin-He Wang, Jiang-Tao Wang, Guang-Wei Deng, Hai-Ou Li, Gang Cao, Ming Xiao, Guang-Can Guo, Kai-Li Jiang, Xing-Can Dai, Guo-Ping Guo

Published 2016-12-27Version 1

Carbon nanotubes (CNTs) have attracted much attention for use in nanomechanical devices because of their exceptional properties, such as large resonant frequencies, low mass, and high quality factors. Here, we report the first experimental realization of parametric strong coupling between two mechanical modes on a single CNT nanomechanical resonator, by applying an extra microwave pump. This parametric pump method can be used to couple mechanical modes with arbitrary frequency differences. The properties of the mechanical resonator are detected by single-electron tunneling at low temperature, which is found to be strongly coupled to both modes. The coupling strength between the two modes can be tuned by the pump power, setting the coupling regime from weak to strong. This tunability may be useful in further phonon manipulations in carbon nanotubes.