Explicit predictions for scanning tunneling microscopy (STM) on interacting
one-dimensional electron systems are made using the Luttinger liquid forma
lism. The STM current changes with the distance from an impurity or boundar
y in a characteristic way, which reveals the spin-charge separation and the
interaction strength in the system. The current exhibits Friedel-like osci
llations, but also carries additional modulated behavior as a function of v
oltage and distance, which shows the spin-charge separation in real space.
Moreover, very close to the boundary the current is strongly reduced, which
is an indication of the interaction strength in the system.