Capture and release of photonic images in a quantum well

The capture of an optical image in the plane of a semiconductor quantum well and the subsequent re-emission of this image in the form of a two-dimensional photon flux is demonstrated. Spatially resolved storage of photonic signals in a two-dimensional lateral potential landscape of the quantum well is employed to imprint optical images in the form of trapped photogenerated charges into the solid. The lateral two-dimensional potential modulation leads to very long storage times by a deliberate spatial separation of photogenerated electron–hole pairs. Once the potential modulation is lifted, the initial optical information is restored and the photographed image is released in a flash of light.