Light detection sensitivity of a vertical cavity structure used in an optical switch device

The light detection characteristics in a vertical cavity surface-emitting laser-type vertical-to-surface transmission electrophotonic device (VC-VSTEP) have been evaluated. To realize a low energy optical interconnection, not only the switching threshold energy but also the light detection sensitivity must be optimized. Maximum sensitivity is achieved when the input light wavelength and the field distribution coincide with fundamental cavity mode characteristics. Under the best matching condition, the input light energy necessary to switch the VC-VSTEP state is easily lower than 1 pJ.