GaAsSb/AlGaAsSb Avalanche Photodiode with High Gain-Linearity: Dataset and Figures

Datasets of the figures found in the manuscript "GaAsSb/AlGaAsSb Avalanche Photodiode with High Gain-Linearity".

Files in this repository correspond to the results in "GaAsSb/AlGaAsSb Avalanche Photodiode with High Gain-Linearity" submitted to IEEE Transactions on Electron Devices.

The figure files contain the graphical figures (.png) found within the manuscript and the data (.xlsx) require to replicate the figures.

Manuscript Abstract:

Avalanche photodiodes (APDs) are widely used in near-infrared optical receivers to detect weak and/or high-speed optical signals. Emerging high-order optical signal modulation formats require the APD’s photocurrents to vary linearly with the signal power. There is, however, a lack of comprehensive understanding of the linearity of APD’s photocurrent and gain versus optical power characteristics underpinned by experimental results. An experimental study was carried out on the linearity of near-infrared APD’s photocurrent and avalanche gain with optical signal power, covering a wide range of optical power and APD’s operating voltage. The work utilized thin 200-nm Al_0.85Ga_0.15As_0.56Sb_0.44 (AlGaAsSb) avalanche region, exploiting their excellent temperature stability compared to thick structures and other commonly used avalanche materials. Three types of linearity behaviors were identified and explained: 1) around the punch through voltage; 2) higher reverse bias and moderate gains; and 3) close to the breakdown voltage and large gains. The best linearity performance, tested under optical power from 0.08 to 750 μ W, was achieved under high reverse bias ( > 18 V) but with moderate gain ( < 10). Our findings of linearity performance are also applicable to near-infrared APDs with other avalanche materials. Furthermore, AlGaAsSb-based APDs exhibit better linearity performance compared to a commercial non-AlGaAsSb APD. At a gain of 10, a 10% attenuation was observed at the output current of 34 μA in the commercial APD compared to 670 μA (20 times higher) in our APD, suggesting the potential of our detector for optical communication links utilizing high-order signal modulation formats.