Shot-Noise-Limited Nanomechanical Detection and Radiation Pressure Backaction from an Electron Beam

Abstract

Detecting nanomechanical motion has become an important challenge in Science and Technology. Recently, electromechanical coupling to focused electron beams has emerged as a promising method adapted to ultra-low scale systems. However the fundamental measurement processes associated with such complex interaction remain to be explored. Here we report highly sensitive detection of the Brownian motion of µm-long semiconducting nanowires (InAs). The measurement imprecision is found to be set by the shot noise of the secondary electrons generated along the electromechanical interaction. By carefully analysing the nano-electromechanical dynamics, we demonstrate the existence of a radial backaction process which we identify as originating from the momentum exchange between the electron beam and the nanomechanical device, which is also known as radiation pressure.

Mass sensing for the advanced fabrication of nanomechanical resonators

“…33 The deposited mass is tracked in real time by monitoring frequency changes of the noise-driven oscillations of the nanotube resonator. Measuring the nanomechanical vibrations relies on e-beam electromechanical coupling 34,35 and is accomplished using the same electron-beam 2 as that used for FEBID. We demonstrate the high sensitivity and versatility of this method, which enables us to address mass changes over more than six orders of magnitude, with a resolution down to the zg range.…”

Review: Deep Learning in Electron Microscopy

“…Definitions of electron microscope noise can include statistical noise [128][129][130][130][131][132][133][134][135] , aberrations 136 , scan distortions [137][138][139][140] , specimen drift 141 , and electron beam damage 142 . Statistical noise is often minimized by traditional denoising algorithms 143,144 , including a variety of denoising algorithms developed for electron microscopy.…”

Optical Transduction for Vertical Nanowire Resonators

“…Besides these optical schemes, electromechanical coupling of nanomechanical motion to focused electron beams has recently emerged as a feasible approach for transduction of vertical SCNWs without the need of specific arrangements. 30,31 However, in addition to the obvious practical limitations imposed by the operation inside a scanning electron microscope, the reported results indicate the presence of radiation pressure back-action effects that perturb the mechanical response of the nanowires. These effects can be of great interest in fundamental studies regarding dynamical cooling of macroscopic degrees of freedom to the quantum ground state, 30 but they may also introduce disadvantageous and complex phenomenology for practical applications.…”

“…Specifically, laser beam deflection schemes have been demonstrated only for nanowires with micron-sized nanowire tips and inverted cone nanowire geometries. , Also, an optical Bragg scattering readout has been recently applied to truly nanometer-scaled vertical nanowire arrays, but it required a periodic arrangement of the arrays and thus a specific nanofabrication process to provide such an arrangement. Besides these optical schemes, electromechanical coupling of nanomechanical motion to focused electron beams has recently emerged as a feasible approach for transduction of vertical SCNWs without the need of specific arrangements. , However, in addition to the obvious practical limitations imposed by the operation inside a scanning electron microscope, the reported results indicate the presence of radiation pressure back-action effects that perturb the mechanical response of the nanowires. These effects can be of great interest in fundamental studies regarding dynamical cooling of macroscopic degrees of freedom to the quantum ground state, but they may also introduce disadvantageous and complex phenomenology for practical applications.…”