Realizing active plasmoniclaser devices with nano-size scale is critical in achieving photonic integrated circuits with the most compact footprint.Although a variety of devices have been studied both theoretically and experimentally recently,most of the previous designs were focused on frequency range far below surface plasmon resonance (SPR) frequency.To further miniaturize laser cavity size,however,it is important to explore lasing in the near-SPR region with much stronger surface plasmon response.