Search

The technology consists of an array of quantum photon sources connected via a sophisticated switching network. This system is designed to produce single pairs of entangled photons at a high rate while actively suppressing the generation of multiple pairs. The key innovation lies in its ability to detect and eliminate instances where two or more entangled photon pairs are generated, effectively reducing noise in the quantum system. The technology operates by providing a heralding pulse that notifies the external system of successful entangled photon generation. When multiple pairs are detected, they are prevented from entering the rest of the system, thereby maintaining the integrity of the quantum information. By combining multiple single-photon sources through its switching network, the technology not only reduces noise but also increases the overall single photon pair generation rate. This dual approach of noise reduction and increased generation efficiency improves qubit transmission rates, potentially by a factor of 10 to 100 over current methods. While still in the early stages of development, the source array represents a significant advancement in quantum communication systems. It addresses the critical need for high-fidelity entangled photon sources, which are essential for various quantum applications, including entangling sensor networks, quantum computer networks, and quantum key distribution for secure communications. As quantum technologies continue to evolve, this source array technology positions itself as a crucial component in the development of large-scale, efficient quantum networks, offering a solution to one of the fundamental challenges in quantum information transmission.

Classical laser communication gimbals are coupled to 105um multimodal receiving fibers for the high-power transmission of data, fine pointing, and tracking. These fibers cannot be used in free space optical communication applications using Quantum Key Distribution (QKD) since polarization state information encoded by QKD photons is not retained. To accommodate low energy QKD photons and high energy data streams necessary for encryption of optical links, the inventor adopted a space-and-wave (SAW) division de-multiplexing approach. The SAW division method uses a double clad fiber with a 9um core and a 105um 1st cladding. This arrangement captures 1590nm wavelength QKD photons in the core channel and a 1555.75nm wavelength data channel in the 1st cladding. By defining wavelength separation between 30-40nm, a single focusing lens can be used to focus only one wavelength to a diffraction limited spot (see figures included). Using this method, a QKD channel is focused to a diffraction limited spot on the 9um core of the double clad fiber. The chosen wavelength separation generates a defocused diffraction pattern with a hollow center, and with remaining optical power in concentric rings outside of the 9um core, yet inside the 105um core. The QKD signal is directed into the 9um core, and the data channel is coupled into the 105um secondary core for traditional data demodulation.