Minimum independently programmable superpixel width

Determine the strict minimum superpixel width that permits independent polarization control of neighboring optical tweezers without appreciable electric-field crosstalk or degradation in control quality.

Background

The optical tweezer polarization is controlled by dividing the spatial light modulator into independently programmable superpixels. The demonstrated configuration uses superpixels substantially wider than the tweezer waist, and additional tests show that a width of approximately three tweezer waists contains more than 99% of the tweezer power while preserving independent control.

The authors report that smaller superpixels may also be usable, but they did not determine the strict lower bound. Establishing this minimum is relevant to scaling the approach to larger tweezer arrays and to assessing the ultimate effect of electric-field crosstalk between neighboring spatial-light-modulator pixels.