HBT Coincidence Trace 2D: Understanding Photon Statistics and Purity

What is the HBT Coincidence Trace?

The HBT coincidence trace, named after its inventors Badhan A. Kalita Hanbury Brown and Richard Q. Twiss, is a method used to study the statistical properties of light. It involves measuring the correlation between photons detected at two different points in time or space. This technique is particularly useful for distinguishing between coherent and incoherent light sources.

In this 2D HBT simulator, you can observe how single-photon purity is quantified using a coincidence histogram (g²(τ)), which measures the probability of detecting photons simultaneously at two detectors.

How Does It Work?

The Hanbury Brown–Twiss experiment relies on the principle that the intensity correlation function, g²(τ), can be used to determine whether a light source is coherent or incoherent. When two detectors are placed at different points and their outputs are correlated over time (τ), the resulting coincidence trace reveals information about the statistical properties of the photons.

In this simulation, you can adjust parameters such as the multi-photon probability, dark count temperature, trigger speed, and operating modes to observe how these factors affect the HBT trace. This allows for a deeper understanding of photon purity and the underlying quantum mechanics.

Why Does It Matter?

The HBT coincidence trace is crucial in various fields, including quantum cryptography, quantum computing, and fundamental studies of light. By quantifying single-photon purity, researchers can better understand the behavior of photons at the quantum level, which is essential for developing technologies that rely on quantum properties.

Moreover, this technique provides a practical way to test the coherence of quantum systems, making it invaluable in both theoretical and experimental physics.

Real-World Applications

The HBT coincidence trace has numerous applications. In quantum cryptography, it can be used to verify the security of quantum key distribution protocols by ensuring that the photons are indeed single-photon states.

In addition, this method is employed in precision measurements and fundamental studies of light-matter interactions, contributing to advancements in areas such as quantum information processing and optical communications.

Frequently asked questions

Try it live

Everything above runs in your browser — open HBT Coincidence Trace 2D — Single-Photon Purity g²(0) | mysimulator.uk and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.