Department of Electrical Engineering, Stanford University, California 94305, USA.
Nat Commun. 2011 Nov 15;2:539. doi: 10.1038/ncomms1543.
Low-power and electrically controlled optical sources are vital for next generation optical interconnect systems to meet strict energy demands. Current optical transmitters consisting of high-threshold lasers plus external modulators consume far too much power to be competitive with future electrical interconnects. Here we demonstrate a directly modulated photonic crystal nanocavity light-emitting diode (LED) with 10 GHz modulation speed and less than 1 fJ per bit energy of operation, which is orders of magnitude lower than previous solutions. The device is electrically controlled and operates at room temperature, while the high modulation speed results from the fast relaxation of the quantum dots used as the active material. By virtue of possessing a small mode volume, our LED is intrinsically single mode and, therefore, useful for communicating information over a single narrowband channel. The demonstrated device is a major step forward in providing practical low-power and integrable sources for on-chip photonics.
低功率、电控光学光源对于满足下一代光互连系统严格的能量需求至关重要。目前的光学发射器由高阈值激光器加外部调制器组成，其功耗过大，无法与未来的电气互连竞争。在这里，我们展示了一种具有 10GHz 调制速度和低于 1fJ/位操作能量的直接调制光子晶体纳米腔发光二极管（LED），其功率比以前的解决方案低几个数量级。该器件为电控，在室温下工作，而高调制速度是由于用作有源材料的量子点的快速弛豫。由于具有小的模式体积，我们的 LED 本质上是单模的，因此可用于通过单个窄带信道传输信息。所展示的器件在为片上光子学提供实用的低功率和可集成光源方面迈出了重要一步。
