Aluminum Plasmonics Based Highly Transmissive Polarization-Independent Subtractive Color Filters Exploiting a Nanopatch Array

Abstract

Nanophotonic devices enabled by aluminum plasmonics are saliently advantageous in terms of their low cost, outstanding sustainability, and affordable volume production. We report, for the first time, aluminum plasmonics based highly transmissive polarization-independent subtractive color filters, which are fabricated just with single step electron-beam lithography. The filters feature selective suppression in the transmission spectra, which is realized by combining the propagating and nonpropagating surface plasmons mediated by an array of opaque and physically thin aluminum nanopatches. A broad palette of bright, high-contrast subtractive colors is successfully demonstrated by simply varying the pitches of the nanopatches. These subtractive color filters have twice the photon throughput of additive counterparts, ultimately providing elevated optical transmission and thus stronger color signals. Moreover, the filters are demonstrated to conspicuously feature a dual-mode operation, both transmissive and reflective, in conjunction with a capability to exhibit micron-scale colors in arbitrary shapes. They are anticipated to be diversely applied to digital display, digital imaging, color printing, and sensing.

Plasmonic Color Filters as Dual‐State Nanopixels for High‐Density Microimage Encoding

“…[1][2][3][4][5][6][7][8][9][10][11][12] Among these examples are color filters based on plasmonics; filters which rely on the resonant interaction between incident photo ns and the free-electrons of nanoscale metal structures. Thus far, filters based on positive nanostructures, [4,7,9,[11][12][13][14][15] filters based on cavity apertures, [2,[16][17][18] and filters which combine both strategies [8] have been shown, each with distinct fabrication and geometrical solutions to achieving color "nanopixels" for selective white-light separation. Plasmonic pixels, in their various forms, hold several advantages reactive ion etching, and inductively coupled plasma deposition).…”

Dual Color Plasmonic Pixels Create a Polarization Controlled Nano Color Palette

“…4 Unlike conventional dye-doped polymers, these plasmonic filters can perform over length scales of <100 nm, making them particularly relevant to ultra-high resolution imaging applications, where the absorption limitations and fabrication challenges surrounding conventional filter miniaturization are proving to be a significant technical hurdle in delivering the next generation of image capture and display technologies. 1,5 Although in their infancy, plasmonic filters consisting of positive nanostructures have already been demonstrated as successful for full-color light separation in both transmissive and reflective systems, 3,[6][7][8][9][10] and have enabled colour image reproduction and display at the microscale; producing images with a 'printed' resolution that extends beyond the diffraction limit, and far exceeds the resolution limit of current color-printing technologies. 2,3 They have also been employed in optical storage technologies, 11 as a means to produce ultra-high resolution stereoscopic images, 9 incorporated with active media to enable a degree of color tunability, 12 and exploited as color reporters for biosensor applications.…”

“…31 Our pixels comprise asymmetric, cross-shaped apertures (acting as intersecting slits aligned perpendicular to one another) in a 100 nm aluminum thin-film, capped with 150 nm of SiO 2 . Aluminum's high plasmon frequency allows visible wavelength transmission with a lower optical loss than gold and silver alternatives, 6,7,10,32 with the added advantage of being abundant, low cost, and fully compatible with current industrial CMOS fabrication processes. Figure 1 shows schematics of an isolated asymmetric nano-pixel, 4 pixels in an array configuration, and an SEM of a typical fabricated pixel array.…”

Polarization conversion based on plasmonic phase control by an ultra-thin metallic nano-strips

“…[1][2][3][4][5][6][7][8][9] However, we still face some challenges for the practical application, such as the reflection geometry makes it inconvenient for practical applications due to the interference between incident and reflected waves. 10 Besides, the metallic film with a thickness smaller than skin depth is high transparent for visible light and half transparent for infrared light, [11][12][13][14] but some transmission devices with larger thickness are typically not perfectly transparent for electromagnetic waves, [15][16][17][18] so the energy loss issues remains unsolved. Moreover, due to the complex structure of the meta-materials/meta-surfaces and the fabrication difficulty, they are not suitable for practical applications.…”