Quantum Efficiency Of Photodetector Calculator

Quantum Efficiency Formula:

\[ \eta = \frac{N_e}{N_p} \]

Quantum Efficiency (η):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Quantum Efficiency?

Quantum Efficiency (η) represents the probability that a photon incident on the photodetector will generate an electron-hole pair, leading to a photocurrent. It is a key parameter in characterizing the performance of photodetectors and other light-sensitive devices.

2. How Does the Calculator Work?

The calculator uses the Quantum Efficiency formula:

\[ \eta = \frac{N_e}{N_p} \]

Where:

\( \eta \) — Quantum Efficiency (dimensionless)
\( N_e \) — Number of electrons collected
\( N_p \) — Number of incident photons

Explanation: The formula calculates the ratio of electrons generated to photons incident on the detector, providing a measure of the detector's efficiency in converting light to electrical signal.

3. Importance of Quantum Efficiency

Details: Quantum Efficiency is crucial for evaluating photodetector performance, optimizing optical systems, and comparing different detector technologies. Higher quantum efficiency indicates better light detection capability.

4. Using the Calculator

Tips: Enter the number of electrons collected and the number of incident photons. Both values must be positive numbers, with the number of photons greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is the range of quantum efficiency values?
A: Quantum efficiency typically ranges from 0 to 1 (or 0% to 100%), where 1 represents perfect conversion of every photon into an electron.

Q2: How does quantum efficiency relate to responsivity?
A: Responsivity (R) is related to quantum efficiency by the formula: R = (η·q·λ)/(h·c), where q is electron charge, λ is wavelength, h is Planck's constant, and c is light speed.

Q3: Can quantum efficiency exceed 1?
A: In conventional photodetectors, quantum efficiency cannot exceed 1. However, in avalanche photodiodes and other devices with internal gain, the effective quantum efficiency can appear greater than 1 due to multiplication effects.

Q4: How is quantum efficiency measured experimentally?
A: Quantum efficiency is typically measured by comparing the photocurrent generated by a known number of photons incident on the detector at a specific wavelength.

Q5: What factors affect quantum efficiency?
A: Quantum efficiency depends on wavelength, detector material, temperature, surface reflections, and the device's internal quantum efficiency.