What you are trying to create is a [thyristor](http://en.wikipedia.org/wiki/Thyristor) and it is lightly different. <!-- Begin schematic: In order to preserve an editable schematic, please don't edit this section directly. Click the "edit" link below the image in the preview instead. --> ![schematic](https://i.sstatic.net/e2cLg.png) <!-- End schematic --> To sustain a transistor on you need current through the gate, in this design the two transistors are feeding output through eachother.