Zero-Added-Loss Entangled Photon Multiplexing Source

Case ID:

This technology is a scheme for optical entanglement distribution in quantum networks based on a quasi-deterministic entangled photon pair source. By combining heralded photonic Bell pair generation with spectral mode conversion to interface with quantum memories, the scheme eliminates switching losses due to multiplexing.

Based on numerical analyses, the protocol is estimated to achieve >102 ebits per second at memory multiplexing of 104 spin qubits for ground distance >104 km, with the spin-spin Bell state fidelity exceeding 99%. The architecture presents a potential blueprint for realizing global-scale quantum networks in the near future.

Global markets for quantum applications maintain high growth across many disciplines during this decade despite the many problems of the early 2020s. Many high-profile companies are investing and researching in the area, and it is likely they will begin integrating hybrid systems within the decade. Given that this innovation stands to impact global-scale networks, it may be extremely worthwhile to explore.   

Multiplexing allows higher single-photon probabilities and lower contamination from higher-order photon states. It can be achieved through using time, space, or frequency degrees of freedom to parallelize spontaneous photon creation across modes, then actively switch the photons into a single output mode based on feedback from heralding detection events. 

Although single photons are ideal for application purposes, often, more than one photon is produced by a source. Once produced, the state tends to encounter nonzero optical loss before reaching the application. This loss is a transformation that results in a state that contains both vacuum and multiphoton components along with the desired single photon.


  • Secure communications
  • Aerospace networks 
  • Optical entanglement distribution
  • Blueprint for global-scale quantum networks


  • Zero added loss 
  • Applicable to global-scale networks
  • High market growth across disciplines
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
Dirk Englund
Kevin Chen