Figure 1

The device consists of a rectangular mesa from which six legs protrude. Legs either are simple rectangles or exhibit a periodically varying width. The legs with spatially varying width are referred to as plasmonic crystals. Their periodicity $p$ is either 25 or $50\mu \mathrm{m}$. All dimensions are in microns.Reuse & Permissions

Figure 2

(a) $B$-field dependence of the photovoltage measured across the source contact and either the contact of the leg with constant width (middle trace) or the leg with a corrugated boundary with period $p=50\mu \mathrm{m}$ (upper trace). The upper curve exhibits large amplitude and less frequent $B$-periodic features, marked as $B_i$ with $i=1,2,\dots$. They are attributed to Bragg reflection of edge magnetplasmons. The distance between adjacent Bragg peaks is denoted as $\Delta B$. The data were recorded for $n_s=3.2\times {10}^{11}{\mathrm{cm}}^{-2}$. The bottom dashed curve displays the photovoltage for an $80\mu \mathrm{m}$ wide corrugated leg. The significant reduction of the Bragg peaks results from a decreased coupling between upward and downward moving waves for this wider plasmonic crystal. (b) Schematic illustration of how the edge magnetoplasmon dispersion is modified in a geometry with a corrugated boundary. For simplicity a linear dispersion has been assumed. Gaps appear at the Brioullin zone boundaries defined by the periodicity $p$. As $B$ is tuned, the dispersion changes and the gaps shift to different frequency intervals.Reuse & Permissions

Figure 3

The photovoltage versus $B$ in a plasmonic crystal with period $p=50\mu \mathrm{m}$ and $\omega$ as a parameter. The period of the Bragg features decreases with increasing $\omega$. The inset plots the $B$ values where Bragg reflection occurs for many frequencies. These results are compared with theoretical simulations based on the dispersion of edge magnetplasmons as derived in Ref. 23. The data were recorded for $n_s=3.2\times {10}^{11}{\mathrm{cm}}^{-2}$.Reuse & Permissions

Figure 4

(a) Influence of the plasmonic crystal period on the photovoltage Bragg oscillation period. A doubling of $p$ halves $\Delta B$. (b) $B$ dependence of the photovoltage in a plasmonic crystal with $p=50\mu \mathrm{m}$ for two densities. To keep the period of the Bragg peaks constant, the microwave frequency has been scaled by approximately the ratio of the densities.Reuse & Permissions