single balanced mixers

Most widely balanced mixers are designed using schottky diodes but why PIN and tunnel diodes are not being used as they are also used for switching actions? plz explain if possible so that i cpold get a satisfactory answer!

PIN diodes are never used as mixers because they switch too slowly.

And Tunnel diodes have a negative resistance region which would at best make the mixer oscillate, they are also horrendously expensive!. Schottky has relatively low capacitance, fast switching performance and low Vf which makes them ideal for mixers.

Brian.