A Magneto-Optical Spatial Light Modulator Driven by Spin Transfer Switching for 3D Holography Applications

Optical and Magneto-Optical Properties of Gd22Fe78 Thin Films in the Photon Energy Range From 1.5 to 5.5 eV

“…Considerable attention has been paid to magnetic and magneto-optical (MO) properties of amorphous ferrimagnetic thin films composed of rare-earth and transition metals because of their useful technological applications [ 1 , 2 , 3 , 4 ]. As one of the important magneto-optical storage materials, GdFe has significant advantages, such as large magnetization density, and possibility to adjust its compensation temperature, coercive and saturation magnetization by changing the composition [ 5 , 6 , 7 ].…”

Two Micron Pixel Pitch Active Matrix Spatial Light Modulator Driven by Spin Transfer Switching

“…We saw some dark elements even after voltage application, which was not switched and was attributed to the pixel defects, which might require larger current or magnetic field. Although we have already demonstrated a reconstructed static image using a magnetic hologram with same magnetic materials used in the spin-SLM [14], the MO image contrast obtained by the MOSFET-driven spin-SLM was low and may not be sufficient for holographic image reconstruction. This is mostly because of the small aperture ratio of 5.5% (lateral size of the MTJ versus size of a pixel).…”

“…There has been significant research activity aimed at enlarging the viewing-zone angle [8,9], and the development of SLMs with very small pixel pitches has become extremely important for the realization of electronic holographic displays with wide viewing zone angles. We have previously proposed a magneto-optical SLM with submicron pixel sizes that is driven by spin-transfer switching (spin-SLM) [10,11], and have shown a 1-dimensional 1 × 10-pixel spin-SLM with a 1 µm pixel pitch without pixel-selection-transistors (passive matrix addressing) and successful control of each pixel by spin-transfer switching (STS) [12]. We have also fabricated a magnetic hologram with 1 µm pixel pitch using same magnetic materials used in the Spin-SLM (2160 × 3840 array layout) which has no electrodes or pixel-selection-transistors to examine the feasibility of magnetic pixels to display an image, and showed a successful reconstruction of a holographic image with wide viewing zone [12].…”

“…As a transistor current supply capability for the STS is proportional to the transistor dimensions of the active matrix, it decreases with transistor size (narrow pitch). So far, we have developed an active matrix addressed spin-SLM (5 × 10 array layout with 5 µm pixel pitch), which is not a sufficiently small pixel pitch and relatively small scale in order to display an image with wide viewing zone [13,14]. Consequently, it is very important to develop spin-SLM with small pixel pitch and larger pixel format for the realization of electro-holography with a wide viewing zone.…”

Current-induced domain-wall motion in patterned nanowires with various Gd–Fe compositions for magneto-optical light modulator applications

“…[1][2][3][4][5][6][7][8] A magneto-optical spatial light modulator (MO-SLM) has been investigated [9][10][11][12][13] to realize a holography display with magnetic tunneling junctions (MTJs) in which magnetization reversal is driven by spin-transfer torque (spin-SLM). 10,12,13) An optical-address type MO-SLM has also been studied. [14][15][16][17] These technologies may potentially make the pixels small and solve the narrow viewing zone, which is a longstanding holography issue caused by insufficiently small pixel of the display devices.…”