Quantum frequency transducer and its applications

Abstract

Quantum frequency transducer (QFT) is an important technology in quantum information processing. QFT can coherently convert quantum state from one wavelength to another wavelength, while the coherence, entanglement, and information encoded in the light beam can be well preserved. There are 2 main application directions based on the intrinsic properties of QFT: (a) quantum frequency interface, which transfer quantum state between different quantum systems work at different wavelengths; and (b) frequency conversion detection, which convert photon from the weak detection ability waveband to the waveband that has better detection ability. In this review article, after giving a brief introduction of the basic principle of QFT, some main progresses for applications of QFT in the aforementioned 2 aspects are described in detail. Finally, we indicate the research trend of the QFT and the problems that remain to be solved in this field.