Photonic Devices Based On Nano Fiber And Its Application In Cavity Quantum Electrodynamics

The ideal working platform for light-matter interactions is the interaction between a single particle and a single photon.In recent years,in view of the advantages of photonic devices in manipulating light fields and matter,researchers have used photonic devices as basic carriers to study the interaction of light and matter,gradually opening a new era of quantum photonics.One of important researches in the field of quantum photonics is the generation of quantum resources,such as the generation,detection,and coherent manipulation of quantum states.Among them,it is one of the key challenges to realize an efficient interface for coherent transfer of quantum states between single photon emitters and photonic qubits.The quantum resources that generate single photons,single-photon emitters play an important role and have great application prospects in quantum computing,quantum information,quantum storage,and Quantum metrology.So far,single-photon sources have been generated in quantum systems based on atoms,ions,molecules,color centers,semiconductor micro-nano crystals,and self-assembled quantum dots.In the field of quantum information,as flying bits,photons play a crucial role in the quantum information transmission process.Therefore,it is a very critical step to efficiently couple the fluorescence of particles into the detection system,which means that the efficient detection and collection of the fluorescence of single particles is important especially.Nanofibers are made of normal optical fibers and the coupling of nanofibers and quantum emitters is also widely used in solid-state particle systems.Compared with gaseous substances such as atoms and ions,solid-state quantum emitters do not require complex techniques for laser cooling and trapping,so it is easier to achieve stable control of particle positions.Various solid-state quantum emitters such as NV color centers in diamond can be used as stable and bright single-photon emitters even at room temperature.In addition,the coupling of nanofibers and solid-state particles also provides a new realization path for the application of integrated and scalable composite systems.In addition,in order to improve the interaction strength of light and matter and further increase the convenience of input and output,Fabry-Perot cavities based on fiber grooves prepared by carbon dioxide laser are proposed and used for cavity quantum electrodynamics research.It is a successful example of traditional Fabry-Perot cavity combined with fiber waveguide.Fiber Fabry-Perot cavities are also widely used to couple with quantum dots,color centers,ions,carbon nanotubes,mechanical oscillators,and liquid helium super-fluids,and realize atomic entanglement,single-photon source,quantum state conversion,quantum repeater and quantum network.This paper mainly introduces the experimental research progress of our laboratory in nanofiber-based photonics devices,including the properties of nanofibers and their evanescent potential fields,the experimental research progress of coupling efficiency enhancement based on the coupling of nanofibers and quantum emitters,and the optical fiber Fabry-Perot cavities.The specific research works are as follows:1)A “nanofiber-microfiber tip” system has been proposed and used to conduct experimental studies on the fundamental properties of nanofibers.First,we use threedimensional finite time domain difference method to numerically simulate the scattering loss of the TOF surface evanescent field caused by the microfiber tip;secondly,we experimentally analyze the distribution of the nanofiber evanescent field and the diameter of the nanofiber non-destructively;thirdly,a bandwidth-tunable optical filter based on nanofiber-microfiber tip is realized on this basis;finally,we measure the mechanical vibration mode of the nanofiber with “nanofiber-microfiber tip” system.2)Three kinds of nanofiber-based resonators with whispering gallery modes are experimentally realized,including:(1)a fiber ring resonator was constructed using a fiber splitter with an adjustable split ratio;(2)a nanofiber-based micro-ring resonators;(3)chemically synthesized microsphere resonators coupled with a nanofiber.3)The coupling between nanofibers and NV color centers has been experimentally explored.First,we have built a coupling system between nanofibers and NV color centers in diamond particles and have verified the feasibility of the system.Second,we have experimentally explored the coupling between a microsphere resonator and the NV color center.4)The integrated structure of the fiber Fabry-Perot cavity has been designed and constructed,and the vacuum system for atomic trapping and the optical path for atomic trapping have constructed.