InGaN nanowire integrated nanophotonics

Summary form only given. A monolithic integrated photonic platform is essentially required for a broad range of applications, including optical interconnect, quantum information processing, lighting, display, and sensing. While Si photonics has been extensively studied, it has several serious shortcomings, including optical absorption in the ultraviolet, visible and telecom wavelengths range, and lack of second order nonlinearity. Moreover, due to the indirect bandgap of Si, a practical Si-based electrically injected laser has not been possible. These critical challenges can be readily addressed by developing a GaN-based integrated photonic platform. GaN has a direct energy bandgap of 3.4 eV and can be further tuned from 6.2 eV to 0.65 eV through alloying with In and Al, which enables a broad range of active photonic devices, including light emitting diodes (LEDs), lasers, and photodetectors operating in the deep ultraviolet (UV), visible and near-infrared spectral range. GaN exhibits strong second order nonlinearity, and the χ ⁽²⁾ coefficient is on the same order as LiNbO ₃ . GaN has a wide transparency window, from ~ 0.36 μm to 13.6 μm [4]. To date, however, the extraordinary potential of GaN-based materials for integrated photonics has been severely limited by the presence of large densities of defects and dislocations in conventional GaN planar heterostructures. In this context, we propose to develop a GaN nanowire based platform for integrated nanophotonics, which can be monolithically integrated on Si and other foreign substrates and are nearly free of dislocations. The paper demonstrates the epitaxy of InGaN nanostructures with controlled shape, composition, and morphology, which will serve as the building block for the emerging GaN integrated nanophotonics. The paper further demonstrates full-color (red, green, blue - RGB) single nanowire LED pixels monolithically integrated on a chip.