High Sensitivity Avalanche Photodetectors

  APD Series Avalanche Photodiodes are semiconductor detectors designed to offer increased sensitivity and lower noise compared to standard PIN detectors. APDs have an additional semiconductor layer which creates an avalanche region with significantly larger electric field strength than in the depletion region of a PIN diode. This allows the initial electron-hole pair created by an absorbed photon to cause a cascade of electron-hole pairs via collisions with the semiconductor lattice. This effect increases sensitivity making APDs ideal for applications that require increased sensitivity, larger bandwidths, low leakage current, and low noise when compared to traditional PIN diodes. The APDs are also sensitive enough and fast enough for the characterization of nanosecond-pulsed solid-state lasers.

The APD210 provides exceptional performance for low-light applications in the 400-1000 nm range, while the APD310 covers the InGaAs range of 850-1650 nm. The APD maintains high gain stability over the 10-40°C operating temperature range by utilizing a temperature-compensation circuit that adjusts the ~150 VDC bias to ensure operation near the breakdown voltage. A 40 dB gain amplifier is integrated into the package and is AC-coupled to the output BNC. The output is matched to a 50 Ω impedance. The APD210 (APD310) detector has an electronic bandpass of 1-1600 MHz (1-1800 MHz) and offers a user-accessible potentiometer, thus leading to a continuous gain adjustment.

The APD Series has SM05 threads for easy integration into Thorlabs' entire family of lens tubes and cage assemblies. The bottom of the detector has a metric (M4) mounting hole and an M4 to 8-32 adapter for post mounting. The compact packaging allows the APD to be substituted directly into an existing setup while maintaining a small footprint on the bench top.

A +15 VDC Power Supply is included.

APD210/ APD310 Specifications

                                 APD210                  APD310
Supply Voltage: +12 to +15 VDC      +12 to +15 VDC
Current Consumption: 200 mA     200 mA
Max Incident Power: 10 mW           10 mW
Operating Temperature: 10 - 40°C         10 - 40°C
Spectral Range: 400 - 1000nm            850 - 1650nm
Detector Diameter: 0.5 mm             0.03 mm
Frequency Range: 1 - 1600 MHz          1 - 1800 MHz
Gain: 2.5 x 105 V/W @ 1GHz,    800 nm 2.5 x 104 V/W @ 1GHz, 1500 nm
Dark State Noise Level: -80 dBm              -80 dBm
NEP (calculated): 0.4 pW/ Hz                  2.0 pW/ Hz
Output Impedence: 50 Ω                  50 Ω
Connector: BNC                   BNC

Features
Gigahertz High-Speed Response
Small Size: 50 x 50 x 45 mm
400-1000 nm and 850-1650 nm Wavelength Ranges Available
Continuously Adjustable Gain: 1x to 100x (ADP210)
Continuously Adjustable Gain: 1x to 10x (ADP310)
SM05 Compatible