OP: A High-Throughput Quantum Photonic Source

Washington University, Saint Louis MO

Investigators

Abstract

Abstract title: A high-throughput quantum photonic source for generating non-classical light Abstract: Non-technical description: The invention of lasers is one of the most important scientific and technological achievements in the history. The laser is already integrated into our daily life: Among their many applications, lasers are used in optical disk drives, laser printers, and barcode scanners; fiber-optic and free-space optical communication; laser surgery and skin treatments; cutting and welding materials; military and law enforcement devices for marking targets and measuring range and speed; and laser lighting displays in entertainment. The laser produces bright, coherent, and tightly-focused light beams which consist of lots of photons (individual constituents of light). When measuring the arrival times of the photons in a laser beam using a photo-dector, the photons arrive randomly. Researchers have discovered that if the arrival times of photons can be orchestrated, these photons could have novel applications in quantum computing and communications that are not possible by using conventional lasers. A light beam that consists of these orchestrated photons is called non-classical light. Scientists have demonstrated the existence of the non-classical light. Nonetheless, to date there exist no efficient methods to produce bright non-classical light. The major hurdle is that although the scientists can coordinate a handful photons, it is very challenging to coordinate a large number of photons in a batch. The project aims to research a quantum light source for generating bright non-classical light. Specifically, we will design a quantum light source, and develop a computational framework to control and to manipulate the photons generated by the light source. Once completed, this project will make possible a new type of quantum light sources such that the output light of the quantum light sources will consist of a large number of coordinated photons so that their arrival times at the photo-detector can be controlled. Such a new quantum light source will be important for practical applications in quantum information science. The capabilities for controlling quantum state of light are of paramount importance for modern society. The success of the project will represent important breakthroughs in quantum optical information processing, a field that has already broadly impacted modern technology and human life. Technical description: The capability of on-chip generation of a large flux of entangled quantum photonic states (antibunched or bunched entangled photons) is necessary to meet the growing demands of a broad range of next-generation scientific and technological applications. Among these are quantum optical information processing, such as quantum computing and quantum key distribution, and quantum (or ghost) imaging. In bunched states, the photons always arrive together at the photo-detector; while in the antibunched states, the photons never arrive together. A promising solid-state route to engineer the quantum photonic states is to use the cavity quantum electrodynamics (QED) systems that relies on the anharmonicity of the Jaynes-Cummings interaction. The PI has shown that the geometry currently employed in experiments - a single Jaynes-Cummings (JC) component sandwiched by two waveguides - have a fundamental tradeoff between high converting efficiency (from independent photons to entangled photons) and the quality of the quantum states (degree of entanglement), and is sensitive to dissipation. Furthermore, the short lifetime of a single JC component severely limits the efficient generation of the quantum photonic states. It is desirable to have high-throughput quantum light sources; however, direct scaling up the number of the cavity QED components would not work, as the photons generated from different cavity QED component would intervene with each other at the output to wash out the intra-state correlations. The goal of this proposal is to computationally research high-throughput quantum photonic sources that produce high-quality entangled quantum photonic states to push the generation of the quantum photonic states well beyond the state-of-the-art.