IR communication

am doing a mini project on home automation using IR(infrared) sensors. so i made the circuit and its workin..now if i release the ir radiation the bulb will be ON state.when i relese the switch it will be off. so i want to use a diode gate(silicon controlled rectifier) so the even when i leave the switch above a holding current bulb will be ON. now will anyone please tell me how to connect it according to its pin configuration !!!