Overview#

What is the PQN?#

The Public Quantum Network (PQN) is a distributed quantum network system that enables the general public to interact with real quantum hardware through a lightweight web interface. Visitors can run quantum experiments — including entanglement verification, quantum key distribution, and quantum random number generation — without any prior knowledge of quantum mechanics.

The network is built around a node-based architecture: each PQN node consists of a backend software stack (pqn-stack) managing hardware and protocols, and a frontend web interface (pqn-gui) for public interaction.

Supported Experiments#

Experiment

Description

CHSH Bell Test

Verifies quantum entanglement by testing Bell inequalities between two nodes

Quantum Key Distribution (QKD)

Generates a shared secret key between two parties using quantum mechanics

Quantum Fortune

Generates random numbers using quantum randomness

Secret Message Sharing (SSM)

Sends a secret message encoded with quantum-generated keys

Tomography

Characterizes quantum states via state tomography

Visibility

Measures the visibility of quantum interference fringes

Architecture#

The PQN uses a two-repo architecture:

  • pqn-stack: Python backend that manages quantum hardware, protocols, and node-to-node communication via a FastAPI server.

  • pqn-gui: Next.js frontend providing the public-facing web interface.

See the Architecture and Architecture pages for details.

Hardware Requirements#

Running the full PQN stack currently requires physical quantum hardware components:

  • TimeTagger: Photon detection timing device

  • Rotators / Rotary Encoders: Polarization basis rotation control (e.g., half-wave plates)

  • Polarimeter: Photon polarization measurement

Dummy instrument drivers are available for software-only testing, but full experiment functionality requires real hardware.

Acknowledgements#

The Public Quantum Network is supported in part by:

  • NSF Quantum Leap Challenge Institute HQAN under Award No. 2016136

  • Illinois Computes

  • DOE Grant No. 712869, “Advanced Quantum Networks for Science Discovery”

For questions, contact the PQN team at publicquantumnetwork@gmail.com.