Quantum Sensors: Advantages, Disadvantages, and Basics

This page explores the advantages and disadvantages of Quantum Sensors, along with basic information about Quantum sensing.

Quantum Sensing Basics

Introduction: A “quantum” refers to the smallest possible unit of radiation, i.e., a single photon. A quantum sensor, therefore, measures PAR (Photosynthetically Active Radiation) or PPFD (Photosynthetic Photon Flux Density).

• PAR: Photosynthetically Active Radiation.
• PPFD: Photosynthetic Photon Flux Density. It represents photon flux integrated over the 400 to 700 nm waveband.

Radiation that drives photosynthesis is known as PAR. PAR can be measured in units of µmoles per meter squared per second. It encompasses radiation in the range of 400 to 700 nm.

Image Courtesy: Apogee Instruments Inc.

The image shows full spectrum and original series quantum sensors manufactured by Apogee Instruments Inc.

Quantum sensors possess quantized energy levels. For example, the APD (Avalanche Photodiode). These sensors can be calibrated for sunlight or electric lights.

They find applications in greenhouses, agriculture, aquariums, underwater environments, and for measuring HPS (High-Pressure Sodium), metal Halide, T5 CWF (Cool White Fluorescent), etc.

Ideally, when a quantum sensor measures light with different spectra, the sensor output depends only on the properties of the light sources and not on the sensor itself.

Advantages of Quantum Sensors

Here are the benefits of using Quantum Sensors:

• Lower Cost: They are generally more affordable than other sensor types.
• Excellent Measurements: They provide accurate measurements across various light sources.
• Precise Field Measurement: They measure E-fields (electric fields) and H-fields (magnetic fields) very accurately across a wide range of frequencies.
• Stable and Calibration-Free: They measure physical quantities against atomic properties, eliminating drift and the need for frequent calibration.
• Improved Sensitivity: Quantum entanglement can be leveraged to enhance sensitivity or precision in measurements.

Disadvantages of Quantum Sensors

Here are the drawbacks of using Quantum Sensors:

• Error Sources: Several error sources can reduce the accuracy of light measurements.
• Spectral Error: Spectral error is one of the main types of errors found in quantum sensors.