An OSA can show and measure the power of an optical source over different wavelengths1. There are various kinds of OSAs, but none of them can analyze a single photon without destroying it1. You need a QOSA for that.

An OSA can show and measure the power of an optical source over different wavelengths. There are various kinds of OSAs, but none of them can analyze a single photon without destroying it. You need a QOSA for that.

It's technically possible to use an optical spectral analyzer (OSA) to analyze a single photon emitted from a single photon emitter source, but it wouldn't be ideal and would face significant challenges:

Challenges:

• Low Probability of Detection: OSAs are typically designed for analyzing signals with many photons, and detecting a single photon can be statistically improbable. Even with high-sensitivity OSAs, the probability of capturing a single photon can be very low, requiring long measurement times or specialized techniques.
• Background Noise: Even in a controlled environment, there can be various sources of background noise, such as stray light or thermal radiation, that can overwhelm the signal from a single photon. This noise can further mask the weak signal and make it difficult to analyze accurately.
• Spectral Resolution: OSAs have a finite spectral resolution, which means they cannot perfectly distinguish between photons with very close wavelengths. This can be problematic for analyzing single photons, as their emissions can be very narrowband.

Alternatives for Single Photon Analysis:

While using an OSA is technically possible, other methods are often more suitable and efficient for analyzing single photons:

• Hanbury Brown and Twiss (HBT) interferometry: This technique uses a beamsplitter to correlate the arrival times of photons at two detectors, allowing for the characterization of single-photon emission statistics.
• Time-correlated single photon counting (TCSPC): This technique measures the time delay between a pump pulse and the emitted single photon, providing information about the lifetime and dynamics of the emitter.
• Confocal microscopy: This technique combines high spatial resolution with single-photon sensitivity, allowing for the localization and characterization of single emitters within a sample.

Conclusion:

While using an OSA for analyzing single photons is technically feasible, it's not the most efficient or effective method. Alternative techniques like HBT interferometry, TCSPC, and confocal microscopy are generally more suitable and provide richer information about the single-photon emission characteristics.

It's important to consider the specific needs and properties of your single photon emitter source when choosing the most appropriate analysis technique.

Selam Tadele and Murtadha Shukur, from your answers, can we consider the using of OSA only as a tool work beneficially at the range of classical analyzing and measuring of classical light. and practical for quantum light like single photon, we must use set up of interferometers, if that your meaning, please provide me with companies name that produce sensors and detectors have quantum ability for detect and analyze a single photon?

regards

Here are some companies leading the way in sensors and detectors with quantum capabilities for detecting and analyzing single photons:

Superconducting Nanowire Single-Photon Detectors (SNSPDs):

• Quantum Design: Pioneering SNSPDs with high efficiency and low dark counts, offering systems and modules for various applications.
• Single Quantum: Specializes in high-performance SNSPDs and integrated systems for demanding research and commercial applications.
• PhoeniX Sensors: Offers a range of SNSPDs and modules with tailored specifications for different needs, including cryogenic and room-temperature options.

Transition Edge Sensor (TES) Detectors:

• NIST: Develops cutting-edge TES detectors for fundamental research and pushing the boundaries of single-photon sensitivity.
• Edwardian Instruments: Provides cryogenic systems and TES detectors for advanced research applications in astrophysics and quantum technologies.
• FastEM: Manufactures high-sensitivity TES detectors and cryostats for demanding research applications requiring ultimate photon resolution.

Silicon Avalanche Photodiodes (APDs):

• ID Quantique: Offers high-performance InGaAs APDs optimized for single-photon detection in telecom and quantum cryptography applications.
• Excelitas Technologies: Provides a variety of APDs with different sensitivities and active areas for various single-photon detection needs.
• Princeton Instruments: Develops advanced photon counting systems incorporating high-sensitivity APDs for scientific research and industrial applications.

Other Emerging Technologies:

• Quantum dots: Several companies are developing quantum dot-based detectors with promising single-photon sensitivity and potential for room-temperature operation.
• Nitrogen-vacancy centers in diamond: Research labs are exploring the use of these centers as single-photon emitters and detectors, offering potential for bioimaging and quantum information processing.

Remember, choosing the best company and technology depends on your specific application requirements, budget, and desired performance characteristics. Consider factors like detection efficiency, dark count rates, operating temperature, spectral range, and ease of integration into your system.

thank you dr. Murtadha Shukur, i will review the equipment in these companies for my experiment about preparation a single photon emitter by vacancies of defects in semiconductor thin film, if you interests we can cooperate in this project

with regards