Quantum transport in Metal-Insulator-Metal structures
Metal-insulator-metal (MIM) nanostructures are being examined for potential applications in high speed optoelectronic devices, such as photodetectors, modulators, wavelength converters, and beam steerers. For ultrathin insulators, quantum tunneling plays a dominant role that ultimately limits the local field enhancement and the tunneling. ALD will enable the deposition of ultrathin and sub-nanometer thickness insulator films to precisely control the tunneling current. MIM diodes using a novel nanowire geometry could provide a new pathway to energy harvesting devices with higher efficiency and polarization insensitivity in the optical regime when compared with traditional rectenna designs. Furthermore, we are studying the linear and nonlinear effects of quantum tunneling in nanoplasmonic systems. The ability to make insulator films of 1 nm or less with controllable thickness would give us a good tool for studying the electromagnetic scattering properties of these systems. It would help to validate the simulations, but also we can plan to design and make nanodevice structures for energy harvesting and photo detection.