Ling Hong-Shi, Wang Shiang-Yu, Hsu Wei-Cheng, Lee Chien-Ping
Institute of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan.
Opt Express. 2012 May 7;20(10):10484-9. doi: 10.1364/OE.20.010484.
We report voltage-tunable 3-5 μm & 8-12 μm dual-band detection in the InAs/Al0.3Ga0.7As/In0.15Ga0.85As confinement-enhanced dots-in-a-well quantum dot infrared photodetectors. The capability in temperature sensing is also demonstrated. Distinct response peaks at 5.0 μm and 8.6 μm were observed in the photocurrent spectra with working temperature up to 140K. The two peaks correspond to the transition paths from the quantum dot ground state to the quantum well state and the quantum dot excited state, respectively. At 77K, the response ratio of the 8.6 μm peak over the 5.0 μm peak changes from 0.29 at -3V to 5.8 at + 4.8V. Excellent selectivity between the two peaks with bias voltage makes the device attractive for third-generation imaging systems with pixel-level multicolor functionality.
我们报道了在InAs/Al0.3Ga0.7As/In0.15Ga0.85As受限增强型阱中量子点红外光电探测器中实现的电压可调谐3 - 5μm和8 - 12μm双波段探测。还展示了其温度传感能力。在高达140K的工作温度下，光电流谱中观察到了分别位于5.0μm和8.6μm处的明显响应峰。这两个峰分别对应从量子点基态到量子阱态以及量子点激发态的跃迁路径。在77K时，8.6μm峰与5.0μm峰的响应比从 - 3V时的0.29变为 + 4.8V时的5.8。两个峰在偏置电压下具有出色的选择性，这使得该器件对具有像素级多色功能的第三代成像系统具有吸引力。
