Nanotube mechanical resonators – tiny electron forces and few quanta of vibrations

Mechanical resonators based on carbon nanotubes feature a series of truly exceptional properties. Carbon nanotubes are the lightest resonators fabricated thus far. The mechanical vibrations are sensitive to the tiny forces associated with the electrons flowing through the nanotube, and vice versa. In this talk, I will discuss our efforts to cool the amplitude of the thermal vibrations to a few quanta [1]. Cooling is achieved using a simple yet powerful method, which consists in applying a constant (DC) current of electrons through the suspended nanotube in a dilution fridge. The origin of the observed cooling is attributed to an electrothermal effect.

[1] C. Urgell, W. Yang, S. L. de Bonis, C. Samanta, M. J. Esplandiu, Q. Dong, Y. Jin, A. Bachtold, Cooling and Self-Oscillation in a Nanotube Electro-Mechanical Resonator, Nature Physics 16, 32 (2020)