Photon Drag Effect due to Berry Curvature

A theoretical investigation reveals that the photon drag effect (PDE) is induced in a grating slab with deformation by the Berry curvature in phase space. It drifts the momentum of light, and gives asymmetric PDE signals in momentum space. Large PDE signals are observed even near the $\mathrm{\Gamma }$ point. This characteristic agrees well with our theoretical results.

Figure 1

(a) Deformed dielectric grating on a metallic film. The deformation $\mathit{u}(\mathit{r})$, defined in Ref. [16], is drawn by a red arrow. The red and blue curves indicate the wave packet and the dielectric grating with deformation, respectively. (b) Translation and refraction due to the Berry curvature. The position shift and refraction are indicated by $\delta {\mathit{r}}_{\mathit{c}}$ and $\delta {\mathit{k}}_{\mathit{c}}$, respectively. The inset shows the top view of the deformed grating.

Figure 2

Schematic of the nondeformed (a) and the deformed (b) MD grating slabs on a Au thin film. The patterned area is $600\mu \mathrm{m}$ squared. (c) Cross section of the MD grating slabs. The period $\mathrm{\Lambda }$, width of the grooves $W$, and height $D$ of the MD grating slabs are 800, 200, and 300 nm, respectively. The thickness of the Au film $h$ is 40 nm. (d) Schematic of the experimental setup for the PDE voltage measurement.

Figure 3

(a) Measured angle resolved reflectivity spectra from the deformed MD grating. (b) Calculation result of the angle resolved reflectivity spectra of the nondeformed MD grating. (c) Snapshot of the magnetic field at the $\mathrm{\Gamma }$ point of the third band. The colors and the arrows indicate the intensity and the direction of the magnetic field, respectively. (d) Schematic of the band structure. The second band is forbidden at the $\mathrm{\Gamma }$ point.

Figure 4

(a) Observed PDE voltage spectra of the nondeformed structure at the incident angles of $\pm 1°$. Observed PDE voltage spectra of the deformed structure at the incident angles of (b) $\pm 0.1°$, (c) $\pm 1°$, and (d) $\pm 10°$.