Mechanically Tunable Bilayer Composite Grating for Unique Light Manipulation and Information Storage

Abstract

Composite gratings play important roles in modern information technology. However, such gratings are generally based on the same structural pattern with limited types, and their structural parameters are difficult to tune, which greatly limit their application. A mechanically tunable composite grating in bilayer film, which orthogonally couples a sinusoidal phase grating and a rectangular phase grating, is developed here. The structural parameters of the grating can be well tuned by mechanically stretching or releasing the grating in the uniaxial direction. Naturally, this property allows tunable light manipulation: that is, a single incident laser beam can be split into a 2D diffraction beams array, and the intensity and propagation angle of each diffraction beam can be precisely controlled via mechanical manipulation of the grating. A theoretical model based on scalar diffraction theory that can quantitatively describe and accurately predict this light manipulation is further established. In addition, after treatment with an electron beam, the tunable structures can be immobilized, which enables the storage of information in the bilayer film. This work may open up new pathways for composite grating fabrication and further extend the applications of composite gratings in diverse fields.

Buckling‐Pattern‐Based Characterization of Stiff Membrane on Soft Film

“…In the literature, the Poisson's ratio of the oxide layer is generally set to about 0.25. [1,15,29] So, in all calculations of SiO 1.8 /PDMS bilayers, we also set the value of μ m to 0.25.…”

“…Oxygen plasma treatment will oxidize the surface of polydimethylsiloxane (PDMS) films. [1][2][3] The presence of surface oxidation is often simply and roughly equivalent to the presence of a stiff layer in many general application scenarios, such as flexible electronics, [4,5] bionics, [6,7] metamaterials, [1,8] and bucklingbehavior studies. [9][10][11] Oxidized surfaces have also been specially studied.…”

Electron Irradiation Frozen Effect in Stiff/Soft Bilayer Films

“…[9][10][11][12][13][14][15][16] Meanwhile, the evolution of buckling structures is believed to follow multiple routes. [7,13,17] The selection of the generates a stiff silicon oxide layer, [28][29][30] as schematically illustrated in Figure 1a. The atomic ratio of Si to O on the oxidized PDMS film surface is 1.8, as determined by the X-ray photoelectron spectroscopy (XPS) (Figure 1b).…”

Dynamic Mechanochromic Optics with Tunable Strain Sensitivity for Strain‐Responsive Digit Display

“…As a result, the concomitant luminescence or chromic behavior can be readily detected by conventional devices or the naked eyes. [17][18][19][20][21][22] Besides molecular level design, micro/ nanoscale structural designs have also well demonstrated their feasibility in achieving high-performance dynamic optics. [23][24][25][26][27][28][29][30] Zeng et al reported a mechanochromism based on strain-dependent microscale cracks, including a series of reversible adaptive optics capable of changing transparency, luminescent intensity, fluorescent color, and revealing/concealing patterns by means of stretching/ releasing.…”