Scientists at Rochester Institute of technology have developed a new technology to quantify entanglement, which is of great significance to the development of next-generation technologies in the fields of computing, simulation and secure communication. A new method for measuring entanglement is reported. When two quantum particles entangle, they have a special correlation, even if the particles are far apart, it will be shown in the measurement. This unique characteristic can only be explained by quantum mechanics, which is also the core of many quantum technologies. Quantum entanglement is a resource that can be used to complete important tasks, such as quantum computing or secure communication.

two entangled quantum particles can produce an unbreakable key that can be used to send information to each other, so that if some third party intercepts the information, according to the laws of physics, they cannot decode the information. As quantum technology becomes more and more complex, users will need a method to calculate how much quantum entanglement exists in a given system. For the system entangled photon pairs in this study, the new technology requires a million times less measurement than the previous methods. Since this technique is based on information theory, the measurement technique has an additional advantage that it never overestimates the entanglement in the system.

it turns out that this is crucial because it means that we will never be surprised to tell you that you have more resources than you actually have. This is especially important for things like secure communication, in which case you avoid interception by your opponent. Entanglement is the core of quantum information processing. It is a powerful and mysterious resource. Its ability in computing, simulation, secure communication and measurement is beyond the classical equipment. To accurately quantify the entanglement of an unknown system requires the complete determination of its quantum state, which even requires a large number of difficult to process measurements for medium-sized systems.

in the new study, we demonstrate a method of strictly quantifying high-dimensional entanglement from extremely limited data. Through adaptive, multistage sampling program improves an entropy, quantitative entanglement witness direct operation compression experimental data acquisition. Only 6456 measurements are needed to prove that the entanglement is 7.11 ±. Two spatially entangled photons share 04 bits. The dimension of Hilbert space is more than 68 billion, and the required measurement value is 20 million times of that of uncompressed method and 1018 times of that of tomography. The new technology provides a general method to quantify entanglement shared in any large number of subsystems.

Boke Park Research / from: Rochester Institute of technology reference journal doi: 10.1038/s41467-019-10810-z James Boke Park Science, technology, scientific research and popular science