Free energy (using just iron and coil)

[overunity7]

Hi, we know when electric current passes through a coil produces a magnetic field and when the coil has a core of iron the magnetic field is increased too much, then I ask you, We can use the iron as free energy? we know all mass is energy thinking in the equation of Einstein but, Would be possible to make a device which has more output than input using this system?

I was thinking a system a little similar to the Hans Coler device but using just coils with iron core and other coils to received the increase of the magnetic fields from the firsts coils and of course it will run using AC current.