I made a circuit in which the LED terminals have a potential difference of 0.1V,So how can i amply this potential difference to 6V using an external power supply.
It's a pretty poor looking circuit anyway, and if it's going to work at all, then layout is going to be absolutely critical. I suspect he's probably built it on a breadboard, where it's never going to work.
There's only 0.1V across the LED, because it's not turned ON.