Heralded-Multiplexed High-Efficiency Cascaded Source of Dual-Rail Polarization-Entangled Photon Pairs using Spontaneous Parametric Down Conversion

Case ID:

This technology is a high-efficiency, high-fidelity method of generating pairs of polarization-entangled photonic qubits. The use of a cascaded source that performs a linear-optical entanglement swap between two spontaneous parametric down conversion (SPDC) sources, to generate a heralded photonic entangled state that has a higher fidelity compared to a free-running SPDC source.

Quantum bits, or qubits, are basic units of quantum information that can be used to store or transmit information just like the classical bit used in traditional computing. They are the fundamental component that enables quantum computers and quantum communication. Entangled qubits are qubits which, regardless of their physical distance, will demonstrate correlated states, over any distance and even when the state of one qubit is changed. This is a fundamental building block of quantum computing and quantum communication.

This technology creates entangled qubits from light particles (photons). There are multiple state-of-the art methods of entangled photonic qubit generation, but they generally suffer from a degree of “noise” in the entanglement state, where the state observed in one entangled qubit will not always equal the state of the other qubit. This technology serves to address this problem, resulting in much higher, near deterministic levels of correlation between two entangled qubits.


  • Quantum communications
  • Quantum computing
  • Quantum information processing


  • High efficiency
  • High fidelity
  • Near deterministic
  • Enables high-rate, high-fidelity quantum communications over long distances
Patent Information:
Contact For More Information:
Richard Weite
Senior Licensing Manager, College of Optical Sciences
The University of Arizona
Lead Inventor(s):
Saikat Guha
Prajit Dhara