High-speed and high-power performances of LTG-GaAs based metal-semiconductor-metal traveling-wave-photodetectors in 1.3-μm wavelength regime

We demonstrated ultrahigh bandwidth and high output power performances of low-temperature-grown (LTG) GaAs-based metal-semiconductor-metal traveling wave photodetectors (MSM TWPDs) in the long wavelength regime (/spl sim/1300 nm). Ultrahigh bandwidth (1.3-ps pulsewidth with 234 GHz transformed 3-dB electrical bandwidth) was achieved with long-absorption-length (70-μm) devices due to the improved microwave property in the MSM TWPDs and their high velocity-mismatch bandwidth. Under high optical power illumination, these 70-μm-long MSM TWPD devices also exhibited superior output power-bandwidth-product performance due to their large absorption volumes. To the best of our knowledge, the demonstrated peak-output-voltage-bandwidth product (3.55 V, 160 GHz, 568 GHz-V) is the highest among the reported photodetectors for Icing optical communication wavelength (1.2 μm-1.6 μm) applications.