High-Speed Mid-Wave Infrared Uni-Traveling Carrier Photodetector Based on InAs/InAsSb Type-II Superlattice
Jian Huang, Zhijian Shen, Zongti Wang, Zhiqi Zhou, Ziyu Wang, Bo Peng, Weimin Liu, Yiqiao Chen, Baile Chen
Abstract
High-speed photodetectors operating at mid-wave infrared are crucial for free-space optical communication and frequency comb spectroscopy. In this letter, we report a high-speed mid-wave infrared uni-traveling carrier photodiode based on InAs/InAsSb type-II superlattice at room temperature for the first time. The device exhibits a cut-off wavelength of around 5.5 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> at room temperature. The responsivity of the device is about 0.6 A/W (at 4.5 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> ) under −1 V at room temperature. The frequency response of the device is characterized by an optical parametric amplification system generating mid-infrared femtosecond pulses. A device with a 20 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> diameter has a 3-dB bandwidth of 12.8 GHz at −4 V. These promising results suggest that the device could be potential candidates to be employed in the emerging high-speed MWIR applications.