Control of photo-induced voltages in plasmonic crystals via spin-orbit interactions

Abstract

There is wide interest in understanding and leveraging the nonlinear plasmon-induced potentials of nanostructured materials. We investigate the electrical response produced by spin-polarized light across a large-area bottom-up assembled 2D plasmonic crystal. Numerical approximations of the Lorentz forces provide quantitative agreement with our experimentally-measured DC voltages. We show that the underlying mechanism of the spin-polarized voltages is a gradient force that arises from asymmetric, time-averaged hotspots, whose locations shift with the chirality of light. Finally, we formalize the role of spin-orbit interactions in the shifted intensity patterns and significantly advance our understanding of the physical phenomena, often related to the spin Hall effect of light.

Revisiting the Photon-Drag Effect in Metal Films

“…Since sgn(ξ p f ) = sgn(ξ expect ), it would be tempting to view this case as representative of the fundamental photon-drag transduction process, but our measurements in vacuum suggest otherwise. This result undermines the interpretation of many reported photon drag measurements on metal films in air [12][13][14][15][16][17][18][19][20][21][22][23][24][25], which implicitly treat the metal surface as pristine and the measured signals, therefore, as wholly intrinsic.…”

“…Recent interest in the metallic photon-drag effect has focused on the role of plasmons, motivated by the ability to engineer the light-metal interaction and to investigate a novel platform for electrical detection of plasmons in nanophotonic systems with multi-terahertz bandwidth [9][10][11]. Photocurrents related to plasmonic interactions are observed for metal films in the Kretschmann-Raether (KR) configuration [12][13][14][15] and with nanostructured or roughened surfaces [16][17][18][19][20][21][22][23][24][25]. But the direction of the measured current has been reported to vary with the excitation conditions in a manner inconsistent with the expectation of a unique direction of momentum transfer [13][14][15][16][17][18].…”

Geometric photon-drag effect and nonlinear shift current in centrosymmetric crystals

“…As we explain below, this transverse nature arises from an intrinsic helical winding of electronic states found in many (centrosymmetric) systems (e.g., HgTe quantum wells, monolayer WTe 2 , graphene) and vividly displays its geometric origin. This intrinsic behavior sharply contrasts with conventional photon-drag in isotropic crystals that is parallel/anti-parallel to the momentum transfer for a longitudinal polarization without angular momentum [19][20][21][22][23][24][25][26][27][28][29].…”

Meta-Optical Chirality and Emergent Eigen-polarization Modes via Plasmon Interactions

“…Another approach that achieves chiral asymmetry is the creation of a linear phase gradient, i.e. , illumination at oblique incidence 18 19 20 21 22 or spatial variation of the unit cell 5 2 23 24 . The chiral response that arises from the linear phase gradient of either of these approaches is associated with extrinsic chirality.…”