SiPM Photon Detection Efficiency Calculator

Quantum Optics & Photonics

Calculate SiPM (Silicon Photomultiplier) photon detection efficiency (PDE), quantum efficiency, and signal-to-noise ratio. Essential for optical sensors, quantum optics, and photonics applications.

Examples

Click on any example to load it into the calculator.

Visible Light Detection

visible

Typical SiPM configuration for visible light detection at room temperature.

Wavelength: 550 nm

Temperature: 25 °C

Bias Voltage: 28.5 V

Breakdown Voltage: 24.5 V

Dark Count Rate: 100 kHz/mm²

Optical Filter Efficiency: 0.85

Fill Factor: 0.65

Microcell Size: 50 μm

Near-Infrared Detection

near-infrared

SiPM optimized for near-infrared wavelengths with enhanced sensitivity.

Wavelength: 850 nm

Temperature: 20 °C

Bias Voltage: 30.0 V

Breakdown Voltage: 25.0 V

Dark Count Rate: 150 kHz/mm²

Optical Filter Efficiency: 0.90

Fill Factor: 0.70

Microcell Size: 35 μm

Low-Noise Application

low-noise

Low dark count configuration for high-sensitivity applications.

Wavelength: 650 nm

Temperature: 15 °C

Bias Voltage: 27.0 V

Breakdown Voltage: 23.5 V

Dark Count Rate: 50 kHz/mm²

Optical Filter Efficiency: 0.95

Fill Factor: 0.60

Microcell Size: 75 μm

High-Speed Detection

high-speed

Configuration optimized for high-speed photon counting applications.

Wavelength: 450 nm

Temperature: 30 °C

Bias Voltage: 32.0 V

Breakdown Voltage: 26.0 V

Dark Count Rate: 200 kHz/mm²

Optical Filter Efficiency: 0.80

Fill Factor: 0.75

Microcell Size: 25 μm

Other Titles
Understanding SiPM Photon Detection Efficiency: A Comprehensive Guide
Explore the fundamental principles of Silicon Photomultipliers, photon detection efficiency, and quantum optics for advanced optical sensing applications.

What is SiPM Photon Detection Efficiency?

  • The Fundamental Concept
  • How SiPMs Work
  • Quantum Efficiency vs PDE
Photon Detection Efficiency (PDE) is a critical parameter that describes how effectively a Silicon Photomultiplier (SiPM) converts incident photons into detectable electrical signals. It represents the probability that a photon incident on the detector will trigger an avalanche and produce a measurable output pulse.
The Physics Behind SiPM Operation
SiPMs operate in Geiger mode, where each microcell acts as an independent photon detector. When a photon is absorbed in the depletion region, it creates an electron-hole pair. Under high bias voltage (above breakdown), this initial charge triggers an avalanche multiplication process, resulting in a large, detectable current pulse.
Components of Photon Detection Efficiency
PDE is the product of three main factors: quantum efficiency (QE), which is the probability of photon absorption; trigger efficiency, which is the probability of initiating an avalanche; and collection efficiency, which accounts for charge collection losses. PDE = QE × Trigger Efficiency × Collection Efficiency.

Key Concepts:

  • PDE typically ranges from 20% to 80% depending on wavelength
  • Higher bias voltage increases trigger efficiency
  • Temperature affects dark count rate and breakdown voltage

Step-by-Step Guide to Using the SiPM PDE Calculator

  • Understanding Your Inputs
  • Choosing the Right Parameters
  • Interpreting the Results
This calculator helps you determine the photon detection efficiency and related parameters for SiPM-based optical systems. Follow these steps to get accurate results for your specific application.
1. Determine Wavelength and Temperature
Start by specifying the wavelength of incident photons in nanometers. SiPMs have wavelength-dependent sensitivity, typically peaking in the visible to near-infrared range. Temperature affects the dark count rate and breakdown characteristics, so specify the operating temperature in Celsius.
2. Set Electrical Parameters
Enter the bias voltage applied to the SiPM and its breakdown voltage. The bias voltage must be above breakdown for Geiger mode operation. The overvoltage (bias voltage minus breakdown voltage) affects trigger efficiency and gain.
3. Specify Noise and Optical Parameters
Include the dark count rate per unit area, which represents noise from thermal electron-hole pair generation. Also specify optical filter efficiency and geometric fill factor to account for system-level losses.
4. Analyze Your Results
The calculator provides PDE, quantum efficiency, overall detection efficiency, signal-to-noise ratio, and detection threshold. These parameters help you optimize your optical system design and predict performance.

Optimization Tips:

  • Higher overvoltage increases PDE but also dark count rate
  • Cooling reduces dark count rate and improves SNR
  • Optical filters can improve signal-to-noise ratio

Real-World Applications of SiPM PDE Calculations

  • Medical Imaging
  • Quantum Optics
  • LIDAR Systems
SiPM photon detection efficiency calculations are essential for numerous applications in modern optics and photonics. Understanding PDE helps engineers and researchers optimize detector performance for specific use cases.
Medical Imaging and PET Scanners
In positron emission tomography (PET), SiPMs detect gamma rays from radioactive tracers. High PDE is crucial for image quality and patient safety, as it reduces scan time and radiation dose. PDE calculations help optimize detector arrays for different gamma ray energies.
Quantum Optics and Single-Photon Detection
Quantum communication and cryptography rely on single-photon detection. SiPMs with high PDE enable efficient quantum key distribution and quantum random number generation. PDE calculations help design systems that maximize quantum bit error rates.
LIDAR and Time-of-Flight Applications
Light Detection and Ranging (LIDAR) systems use SiPMs for distance measurement and 3D mapping. PDE affects detection range and accuracy. Calculations help optimize detector arrays for automotive, robotics, and environmental monitoring applications.

Application Examples:

  • PET scanners require PDE > 30% for clinical use
  • Quantum cryptography needs PDE > 10% for practical systems
  • LIDAR systems benefit from PDE > 40% for long-range detection

Common Misconceptions and Correct Methods

  • PDE vs Quantum Efficiency
  • Temperature Effects
  • Wavelength Dependence
Several misconceptions exist about SiPM photon detection efficiency and its measurement. Understanding these helps avoid errors in system design and performance evaluation.
PDE is Not the Same as Quantum Efficiency
A common mistake is equating PDE with quantum efficiency. While related, they are different parameters. Quantum efficiency refers only to photon absorption, while PDE includes the entire detection process including avalanche triggering and charge collection.
Temperature Effects on Performance
Many users underestimate the impact of temperature on SiPM performance. Temperature affects breakdown voltage, dark count rate, and gain. Cooling can significantly improve signal-to-noise ratio, especially for low-light applications.
Wavelength Dependence of PDE
PDE varies significantly with wavelength due to the wavelength-dependent absorption coefficient of silicon. Peak efficiency typically occurs in the visible range (500-600 nm) and decreases in the ultraviolet and near-infrared regions.

Correction Methods:

  • Always measure PDE at the specific wavelength of interest
  • Account for temperature variations in system design
  • Consider optical coupling efficiency in overall system performance

Mathematical Derivation and Examples

  • PDE Formula Derivation
  • Quantum Efficiency Calculation
  • Signal-to-Noise Analysis
The mathematical framework for SiPM photon detection efficiency involves several interconnected parameters. Understanding these relationships helps optimize detector performance and predict system behavior.
Photon Detection Efficiency Formula
PDE can be expressed as: PDE(λ,V,T) = QE(λ) × Ptrigger(V,T) × ηcollection, where λ is wavelength, V is bias voltage, T is temperature, QE is quantum efficiency, Ptrigger is trigger probability, and ηcollection is collection efficiency.
Quantum Efficiency Calculation
Quantum efficiency depends on the absorption coefficient α(λ) and the depletion region width W: QE(λ) = 1 - exp(-α(λ) × W). The absorption coefficient varies with wavelength, peaking in the visible range for silicon.
Trigger Probability and Overvoltage
Trigger probability increases with overvoltage (Vbias - Vbreakdown) and can be approximated as: Ptrigger ≈ 1 - exp(-(Vbias - Vbreakdown)/Vcharacteristic), where V_characteristic is a device-specific parameter.
Signal-to-Noise Ratio Analysis
SNR = (PDE × Nphotons) / √(Nphotons + Ndark), where Nphotons is the number of incident photons and N_dark is the dark count rate. This relationship shows how PDE affects detection sensitivity.

Mathematical Examples:

  • For 550 nm light: QE ≈ 0.8, typical PDE ≈ 0.4-0.6
  • Overvoltage of 4V typically gives P_trigger ≈ 0.9
  • SNR improves with √PDE for photon-limited detection