Design of Harmonic AFM Probe Subjected to van der Waals Force in the Modified Couple Stress Theory

<div>Stepwise width of a micro probe: (a) width variations of three probes with integer multiples of frequencies; (b) 3D cross section of the probe with frequency ratios <span class="nowrap"><svg height="12.5794pt" id="M75" style="vertical-align:-3.29107pt" version="1.1" viewbox="-0.0498162 -9.28833 96.8817 12.5794" width="96.8817pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M293 -169V-141C218 -131 209 -90 209 -44C209 19 222 85 222 152C222 207 198 255 139 269V273C199 286 222 334 222 388C222 454 209 523 209 588C209 632 218 671 293 681V709C234 709 148 695 148 577C147 513 155 438 155 372C155 337 152 291 64 285V256C152 250 155 204 155 169C156 105 148 31 148 -41C148 -157 234 -169 293 -169Z"></path></g><g transform="matrix(.013,0,0,-0.013,4.511,0)"><path d="M495 86L479 114C446 82 419 66 409 66C401 66 401 72 406 97C420 166 436 231 453 297C489 435 454 448 428 448C406 448 384 439 354 422C305 394 222 327 161 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Mathematical Problems in Engineering

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Figure 3

Figure 3: Design of Harmonic AFM Probe Subjected to van der Waals Force in the Modified Couple Stress Theory 