Fig. 2: Nanophotonic design of HPhPs structures on hBN via controllable and tunable localized conductivities of the SNO substrate.
From: Reconfigurable hyperbolic polaritonics with correlated oxide metasurfaces
a SKPM surface potential image of pristine SNO with conductive writing patterns made by applying potential at the c-AFM tip, 10 V (three top rows) and 8 V (three bottom rows). b Corresponding s-SNOM second harmonic near-field amplitude, s2, image of panel (a) taken at λ = 6.9 µm excitation wavelength. S-SNOM second harmonic near-field amplitude, s2, image of panel (a) with a hBN flake transferred on top of the pattern imaged at c λ =:6.9 µm excitation wavelength and at d λ = 6.45 µm. e SKPM surface potential image of pristine SNO with conductive writing patterns made by applying 10 V potential at the c-AFM tip. f Corresponding s-SNOM second harmonic near-field amplitude, s2, image of panel e taken at λ = 6.9 µm excitation wavelength. S-SNOM second harmonic near-field amplitude, s2, image of panel (a) with a hBN flake transferred on top of the pattern imaged at g λ = 6.9 µm excitation wavelength and at h λ = 6.45 µm. i Near-field second harmonic amplitude, s2, images of the conductive pattern on hBN/SNO and Pt electrode shown on the left of the patterns before H2 exposure i, after H2 exposure j, zoomed in image after H2 exposure k followed by erasing made by applying 10 V potential at the c-AFM tip (l). m Near-field second harmonic amplitude, s2, line profiles extended along the dashed lines in panels b–d (orange, neon green, and violet, respectively). n Near-field second harmonic amplitude, s2, line profiles extended along the dashed lines in panels g, h, k, and l (blue, orange, green, and violet respectively). White dashed lines in panels e, i, j, k, and l represent the charge written region on SNO. All scale bars indicate 1 µm.
