All-optical switch for input-output-independent logic gate construction in atomic systems

We propose an input-output independent logic gate via optical switching effect in a four-level tripod atomic model. The intensity, line shape and detuning of the probe field and the switching field of the switch are investigated. Unlike previous research on all-optical switches, there are two switching fields as inputs and one probe field as output in this model. This enables an 'or' logic gate in which the input and output can be controlled independently. Thus, we can control the output 'on' and 'off' through two switching fields and freely adjust the strength of the output without changing the switching field. By adjusting the coherence conditions, ideal optical switching phenomena such as higher switching efficiency and larger switching speed are realized, which provides new ideas for designing optical communication or optical gain devices.