The photonic crystal (PC) nanocavity laser is an extremely promising optical source for optical interconnects since it’s been shown to have nanowatt thresholds and high speed modulation rates can operate in continuous wave mode at room temperature and can be easily integrated with passive elements such as PC waveguides. In order to be practical however electrical pumping techniques must be developed for the PC nanocavity. Researchers at Stanford have developed a novel technique for electrically pumping photonic crystal membrane nanocavities using a lateral p-i-n junction. The p-i-n junction can be defined by any number of methods including ion implantation regrowth or diffusion doping. The junction is designed so that current flow is directed into the nanocavity region. A primary advantage of this technique is that current flow can be defined lithographically thus making it compatible with arbitrary photonic crystal designs. The technology can be used in any photonic crystal device that uses a nanocavity such as: a. electrically pumped photonic crystal LED’s or lasers; b. electrically driven photonic crystal electro-optic devices such as modulators or splitters; and c. controllably charging a quantum dot in a photonic crystal cavity. This invention provides numerous advantages over the vertical p-i-n junction including easier fabrication and the ability to be utilized with arbitrary PC design. It enables photonic devices to operate at lower voltage thresholds and higher speeds but with greater power consumption efficiency. Compared to previously used techniques this approach enables integration of many electrically injected photonic crystal devices. All these advantages make the invention ideal for high-volume manufacturing of photonic devices as well as for the creation of integrated photonic circuits complex photonic chips and high performance biomedical sensors.
1) Monolithic integration of all optical components interconnected to form an optoelectronic circuit. 2) Ease of fabrication 3) Compatible with all membrane photonic crystal designs 4) This method can be used with any cavity design. 5) More efficient - current flow can be lithographically directed to flow only where it is useful in the cavity region making the devices more efficient. 6) Easier to integrate with other photonic devices -which is impossible with other methods that use conductive substrates.