Thermoelectrically cooled NIR (near infrared) detector with low noise and high-speed response InGaAs PIN photodiodes have small terminal capacitance for high-speed response and also feature high shunt resistance and very low noise. G8605 series of InGaAs PIN photodiodes are thermoelectrically cooled types that decrease the dark current to achieve high D*. One-stage (-10 C) and two-stage (-20 C) thermoelectrically cooled types are provided.