Heterostructure devices incorporate carbon nanotube technology to implement rectifying devices including diodes, rectifiers, silicon-controlled rectifiers, varistors, and thyristors. In a specific implementation, a rectifying device includes carbon nanotube and nanowire elements. The carbon nanotubes may be single-walled carbon nanotubes. The devices may be formed using parallel pores of a porous structure. The porous structure may be anodized aluminum oxide or another material. A device of the invention may be especially suited for high power applications.