The development of quantum communication technology in China has progressed through several stages. Starting from the study and research phase in 1995, by the year 2000, China had completed a quantum key distribution experiment spanning 1.1 km. The period from 2001 to 2005 was a phase of rapid development during which successful quantum key distribution experiments over distances of 50 km and 125 km were realized .
In recent years, China has made significant breakthroughs in quantum communication. China was the first to launch a quantum science experimental satellite, "Micius," and has constructed a quantum secure communication line spanning thousands of kilometers between Beijing and Shanghai. China has successfully built an integrated quantum communication network from earth to space with a total span of 4600 kilometers. In addition to this, China has also achieved remarkable progress in quantum computing. For instance, China has developed the world's first prototype of a photonic quantum computer, successfully built a quantum computing prototype "Jiuzhang" with 76 photons, and has successfully constructed a programmable superconducting quantum computing prototype "Zu Chongzhi" containing 62 qubits.
The use of passive component in quantum communication systems is of paramount importance. For instance, devices such as microwave attenuators, directional couplers,power dividers , microwave filters, phase shifters, and microwave isolators may be utilized. These devices are primarily employed to process and control the microwave signals generated by quantum bits.
Microwave attenuators can reduce the power of microwave signals to prevent interference with other parts of the system due to excessive signal strength. Directional couplers can split microwave signals into two parts, facilitating more complex signal processing. Microwave filters can filter out signals of specific frequencies for signal analysis and processing. Phase shifters can alter the phase of microwave signals, used to control the state of quantum bits. Microwave isolators can ensure that microwave signals propagate only in one direction, preventing signal backflow and interference with the system.
However, these are only a part of the passive microwave components that might be used in quantum communication. The specific componens to be used would need to be determined based on the design and requirements of the particular quantum communication system.
Concept provides ful range of passive microwave components for quantum communication
Post time: Jun-01-2023