Figure 2. Brownian motion detection of a SiC nanowire in a SEM.

(a) SEM static images of the nanowire used in the present study. The magnification coefficients are × 1,500 (left, scale bar, 20 μm) and × 250,000 (right, scale bar, 100 nm). The nanowire is mounted into the horizontal plane (x,y), with respective origins on the nanowire axis (right) and at the apex of the Tungsten micro-tip (left). (b) Calibrated ETD noise spectrum acquired in spot mode, with the electron probe being set at y₀=10 μm. Inset shows a line scan taken at the same longitudinal distance, and which served for determining the local slope . The dark dot indicates the transverse position at which the spectrum was acquired. (c) Brownian motion spectrum associated with the second harmonic vibration around Ω/2π≃122.5 kHz.