Abstract

The vertical to surface transmission electrophotonic (VSTEP) device, which consists, for example, of pnpn structure,¹ has multiple functions such as light emission, light absorption, thresholding, and latching. This multifunctional feature makes it easy to construct a cascaded interconnection, compared with the use of a spatial light modulator, because sources and optics for readout are not necessary. To achieve a stable operation, differential VSTEP devices, which consist of two VSTEPs connected in parallel through a common load resistance, are used. Cascaded interconnection characteristics were measured by using a surface-emitting laser mode VSTEP with vertical cavity.² A 150-fJ and a 1.7-pJ switching energy have been achieved at 1- and 10-MHz clock frequency, respectively.³ The drive clock signal frequency is >10 MHz, which includes reset, precharge (light absorption), and set times. This frequency may be improved by optimizing the device structure.

© 1991 Optical Society of America