Electromigrated Nanogaps are gaps formed in metallic bridges formed by the process of electromigration.
A nanosized contact formed by electromigration acts like a waveguide for electrons. The nanocontact essentially acts like a one-dimensional wire with a conductance of
G
=
2
e
2
/
h
. The current in a wire is the velocity of the electrons multiplied by the charge and number per unit length,
I
=
v
e
N
/
L
or
G
=
v
e
N
/
L
V
. This gives a conductance of
G
=
v
e
2
N
/
L
E
. In nano scale bridges the conductance falls in discrete steps of multiples of the quantum conductance
G
=
2
e
2
/
h
.
Electromigrated Nanogaps have shown great promise as electrodes in use in molecular scale electronics.
Researcher have used feedback controlled electromigration to investigate the magnetoresistance of a quantum spin valve.
