Resonant tunnelling diode photodetector operating at near-infrared wavelengths with high responsivity

Resonant tunnelling diode photodetectors with a 600 nm In0.53Ga0.47As absorption layer were fabricated by molecular beam epitaxy. The current–voltage characteristics of devices with different mesa diameters were tested and the negative differential resistance was observed in all devices. The responsivity of the detector was measured to be 4.19 × 105 A/W at 77 K and 1.92 × 104 A/W at room temperature under incident light with a power of 3.1 nW.