The Experimental Research Of Miniaturized Physical System In The Sr Optical Clock

The measurement precision of the Sr optical lattice clock has reached 10^-19 level,which is currently the most accurate atomic clocks in the world,and it's expected to become the new generation of time and frequency standard.Combining high accuracy Sr optical clock and microgravity environment,which is unique in space station,to develop space cold atomic Sr optical clock is to become a new research direction.Due to the huge volume and complicated structure of the optical clock system itself,and subject to the limit of the special conditions of the space station,the primary problem is the miniaturization of the system in the course of the development of space cold atomic optical clock.This thesis focuses on the miniaturization of physics system based on the Sr optical clock,and the miniaturization of Sr physics system has been successfully realized in the experiment.The research design adopts the Sr Dispenser which is vacuum built-in heating mode as a device to create the atomic beam,and successfully realized the high beams,low density,low power consumption and small volume of Sr atomic source.The research completes the design and tests of the zeeman slower made of 12 individual coils.As a result,about 16.4%of the atoms are actually slowed down to 75 m/s.Designed and implemented the anti-Helmholtz coils inside the vacuum chamber.In the experiment,its axial magnetic field gradient is 43 Gs/cm,and the heating power is less than 1 W.Thus a small current,low power consumption and small volume of magneto-optical trap is builded,and greatly reduces the volume of physical system of Sr optical clock.Preliminary realizing the miniaturization of physics system of Sr optical clock,and its volume is about 1/10 of the system in the ground laboratory.Based on the new and small physics system of Sr optical clock,the first stage cooling and trapping is achieved in the experiment.The population of cold atoms finally trapped in the MOT is 1.6×10⁶ of ⁸⁸Sr,which by collecting and estimating the fluorescent of the atoms,and its tempreture tested by TOF is 10.6 mK.Besides these,the population of ⁸⁷Sr cold atoms is 1.5×10⁵.In addition,the research studies the effect of the 707 nm and 679nm repumping lasers to the loading of cold atoms in the MOT.In the end,the number of atoms has been dramatically increased 5 times.The research designs a ring-shaped permanent magnet zeeman slower,and tests its performance.Meanwhile,the factors that may affect the velocity,which include the frequency and power of the slowing laser and the tempreture of the Dispenser are analysised.In addition,studying the shortest length and the best distribution of the magnetic field of the zeeman slower for the sake of the miniaturization of physics system in Sr optical clock.When the length of zeeman slower is around 8-12 cm,the number of atoms being 10⁶,which is about 11%of the total atomic number,can be traped into the MOT.All of these have significance to realize the permanent magnet zeeman slower and the miniaturization of physics system in Sr optical clock.