An example of a non-ohmic conductor is a junction diode. The IV curve of it is given below:
A junction diode is a semiconductor diode that conducts only in one direction, i.e., in the forwarding direction.
The PN junction diode is made up of semiconductor material. It is always conducted in one direction and hence used for rectification. The PN junction diode has two terminals namely anode and cathode. The current flows from anode to cathode.