High-Sensitivity Multiband Detection Based on the Local Enhancement Effect of an Electric Field at Terahertz Frequency

<div>(a) Reflectance spectra of the metamaterial-based absorber; (b–d) diagrams of the relative impedance at <span class="nowrap"><svg height="12.7178pt" id="M40" style="vertical-align:-3.42947pt" version="1.1" viewbox="-0.0498162 -9.28833 79.8775 12.7178" width="79.8775pt" 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="M619 670C619 686 593 712 555 712S459 686 410 634S335 504 320 430H250L219 400L222 388H312L258 73C223 -133 201 -166 187 -180C175 -191 158 -199 140 -199C123 -199 88 -188 74 -172C68 -166 63 -164 54 -171C38 -185 23 -201 23 -215C23 -236 60 -261 93 -261C122 -261 161 -247 207 -200C268 -138 300 -71 337 94C365 220 376 277 394 387L501 399L521 430H401C432 623 464 665 501 665C524 665 544 651 567 627C577 617 583 618 592 625C601 631 619 651 619 670Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,6.721,3.132)"><path d="M433 39L423 65C413 59 399 54 387 54C370 54 352 69 352 114V299C352 352 342 392 307 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270 117 142 31 15L38 0H367C382 40 399 86 413 125L387 138Z"></path></g></svg>,</span> respectively.</div>

Journal of Sensors

fig2

Figure 2

Figure 2: High-Sensitivity Multiband Detection Based on the Local Enhancement Effect of an Electric Field at Terahertz Frequency 