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(a) and (b) SEM image of a pristine dipole antenna gap. Long term (>1 h) exposure to the high field THz radiation restructures the dipole antenna shape. (c) and (d) The reformed gold antenna. The zoom in reveals the fine structure inside the gap.
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Context 1
... TIFEE is an extreme example of the complete suppression of quiver motion, due to the local field enhancement, and may work as a well-collimated electron source. Figure 4 shows SEM images of dipole elements with and without exposure ($1 h) to the THz field. Figures 4(a) and 4(b) are images of the pristine antenna structure (capaci- tive gap $2 lm). ...
Context 2
... 4 shows SEM images of dipole elements with and without exposure ($1 h) to the THz field. Figures 4(a) and 4(b) are images of the pristine antenna structure (capaci- tive gap $2 lm). Figures 4(c) and 4(d) show the images of the modified gold antenna after exposure. ...
Context 3
... 4(a) and 4(b) are images of the pristine antenna structure (capaci- tive gap $2 lm). Figures 4(c) and 4(d) show the images of the modified gold antenna after exposure. Near the antenna gap, the amorphous gold has moved inwards, shrinking the gap size to 1 lm, as indicated by Figure 4(d). ...
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