Controlled Growth And Device Application Of Erbium Silicate With Long-lived Fluorescence

In the 21st century,people have entered a highly information age.The massive amount of information generates ever-increasing demands for processing,storage and transmission of information.To achieve higher-speed transmission,exchange,and handling of information,silicon-based optoelectronics can take advantage of silicon-based microelectronics’advanced and mature process technology,high-density integration,low price,and high transmission rate,high anti-interference,and low power consumption of photons.However,silicon is an indirect bandgap semiconductor with low luminous efficiency and large photothermal coefficient,which is significantly affected by temperature.Therefore,the manufacture of small-sized silicon-based active devices is remains challenging.Under the excitation of 980 nm laser,erbium ions have good luminescence properties in the near-infrared optical communication band,1.5μm,which has been used to make erbium fiber waveguide amplifiers and other active devices.The gain characteristics of luminous materials that containing erbium ions depend on the concentration of erbium ions.It is reported that the erbium compound crystal material,such as erbium silicate,has an erbium ion concentration that 1-2orders of magnitude higher than previous erbium-doped materials,and has excellent gain characteristics,which making it possible to realize optical amplifiers and lasers.The fluorescence lifetime of erbium silicate material is a very important parameter,which determines the difficulty of population inversion,that is,the threshold value of pump power to achieve net gain of laser and amplifier.In this paper,single-source chemical vapor deposition is used to successfully prepared erbium silicate nanomaterials with various morphologies.The morphology,crystal structure and optical properties of the samples are investigated through structural and optical characterization.The growth method of erbium silicate nanowires and their viability as nano temperature monitors are investigated on this basis.The main research contents are as follows:（1）Erbium silicate nanowires and nanosheets,Er₃（SiO₄）₂Cl,were prepared by chemical vapor deposition method without silicon source.Photoluminescence and basic structure test show that the sample has good luminescence properties and high-quality single crystal structure.This method of growing erbium silicate nanowires using a single source material,where the silicon is derived from a small amount of evaporation of the silicon wafer as the growth substrate.This not only saves the use of the silicon source,but also avoid crystal burial of the deposition area of the material due to build-up of excess source material.（2）The diameter of erbium silicate nanowires is about 200 nm,with few lattice defects,and the near-infrared luminescence lifetime at 1.5μm reaches 7.4 ms.According to the theory that the ²H_11/2 and ⁴S_3/2 levels of erbium ions can be thermally coupled,the feasibility of erbium silicate nanowires as optical temperature detectors is studied.The energy difference between ²H_11/2 and ⁴S_3/2 levels is calculated to be 720cm^-1,and the sensitivity of the sample to temperature increases with the increase of the temperature.