Cooling and self-oscillation in a nanotube electromechanical resonator

Abstract

Nanomechanical resonators are used with great success to couple mechanical motion to other degrees of freedom, such as photons, spins, and electrons [1,2]. Mechanical vibrations can be efficiently cooled and amplified using photons, but not with other degrees of freedom. Here, we demonstrate a simple yet powerful method for cooling, amplification, and self-oscillation using electrons. This is achieved by applying a constant (DC) current of electrons through a suspended nanotube in a dilution fridge.We demonstrate cooling down to 4.6 ± 2.0 quanta of vibrations. We also observe selfoscillation, which can lead to prominent instabilities in the electron transport through the nanotube. We attribute the origin of the observed cooling and self-oscillation to an electrothermal effect. This work shows that electrons may become a useful resource for quantum manipulation of mechanical resonators. * These authors contributed equally to this work. 1 arXiv:1903.04892v1 [cond-mat.mes-hall]

Self-driven oscillation in Coulomb blockaded suspended carbon nanotubes

“…Further studies verified the mechanical nature of these transport signatures [6,7]. Similar features were recently observed in Kondo [4] and high-bias tunneling transport [8], where advanced readout techniques confirmed the large amplitude and bistability of self-driven states. In these prior studies, the transport signatures of selfdriven oscillations appeared as instabilities in the currentcarrying transport regime.…”

“…The stable, large-amplitude oscillations discussed above may interfere with the usual operation of these devices as nanomechanical force or mass sensors at subkelvin temperatures. However, these oscillations may exhibit narrower linewidths than the intrinsic resonator linewidth [22], and a properly tailored electromechanical coupling can provide a pathway to active cooling of the mechanical state [4]. Additionally, with sensitive frequency-resolved readout [9], self-driven oscillations may be useful for sensitive mass/force detection without the need for high-frequency external excitation at the device [23].…”

“…Under certain conditions, a positive feedback between the tunneling of charge carriers on/off the CNT and mechanical motion can lead to self-driven oscillations [3]. The study of self-driving phenomena is itself fundamentally interesting, with implications for mass/force sensing, and the underlying carrier-motion coupling has potential application for mechanical cooling [4]. Self-driven oscillations were first observed in the electronic transport of suspended CNT transistors with high mechanical Q factors [5].…”

From Transparent Conduction to Coulomb Blockade at Fixed Hole Number

“…Given that the measurement took place with the device immersed in liquid helium, and that a high magnetic field was present, mechanical self-activation is unlikely to be the cause. [20,21,[25][26][27] A self-driving mechanism would need to overcome both viscous damping and dissipation due to induction. An unambiguous decision whether the sharpest such features here in our measurement are sudden switching events, as expected for the onset of mechanical instability, is not possible from the data set due to the averaging times of lock-in amplifier and multimeter.…”

A Suspended Silicon Single‐Hole Transistor as an Extremely Scaled Gigahertz Nanoelectromechanical Beam Resonator

“…This hybrid architecture has attracted significant research interests in the last decade, but mostly with prototypes using carbon-based materials and based on field-effect mechanical-vibrationto-current transduction. [5][6][7][8][9] The strong piezoresistive effect in Si could enable another signal transduction approach. [10] Moreover, the well-developed Si technology provides the capability for largescale integration.…”