(a) The geometry of the FEM simulation showing the beam (blue) and the oxide substrate (yellow) with a 500 nm deep pit. The beam is long. (b) The transient time response of the device shown in (a) for an excitation frequency of 1 MHz. The response can be well described with a damped oscillator model.
The thermal response of the released nanomechanical device. (a) The frequency response showing the typical behavior of a first-order low pass with a cutoff frequency of 580 kHz using 1 nW actuation thermal power. The frequency response is measured at the center of the beam where the temperature reaches its maximum due to thermal isolation. (b) The time dependent thermal ring down for the same device, showing the typical exponential decay of a first-order low pass. The initial device temperature was set to 380 K.
(a) The temperature distribution within the waveguide for an absorbed thermal power of 0.5 nW. Because the beam is thermally isolated, heat can only escape by diffusion into the substrate. Therefore the maximum temperature is reached at the center of the beam. (b) The thermal profile along the center of the waveguide in the direction. The temperature profile in the -direction remains almost constant.
(a) The vertical displacement resulting from the thermal profile in Fig. 3(a) with a peak temperature of 0.13 mK. The maximum displacement is reached at the center of the beam where the temperature is highest. (b) The vertical displacement of the center line of the waveguide. The displacement is shown for four different peak temperatures ranging from 32.5 to .
Vertical displacement and maximum temperature in dependence of absorbed thermal power. Note that the corresponding optical power on the beam is much higher.
The nomenclature used to determine the maximum deflection of a doubly clamped beam due to a thermal load. The mechanical boundary conditions are set to be hinged-hinged, which corresponds to the solution found using FEM. The deflection angle of the beam at the clamping points is denoted by .
Analytical solution of the problem of elastica for the long nanoscale beam. (a) The vertical displacement in femtometer as a function of the peak beam temperature. (b) The mode shape of the beam obtained analytically and by FEM for a peak beam temperature of 0.4 mK.
(a) An image of the MZI system taken with an optical microscope. The MZI has a path difference of between the top and the bottom arms. (b) A SEM picture of a released NEMS beam of length. The beam has a quality factor of 1850 in vacuum.
(a) The temperature response of a released (black) and unreleased (red) NEMS device. The response of the unsuspended device is due to diffusive substrate heating. The response of the released device is composed of the response of the beam (green line), the mechanical peak, plus the background response of the substrate. (b) The temperature response of the suspended NEMS beam of length. The cutoff frequency obtained from the fit with a first-order low pass is 530 kHz, close to the simulated value of 580 kHz.
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