The Study For Laser Cooling And Trapping Neutral Sodium Atoms

In the field of cold atom research,the preparation of cold atoms is undoubtedly the first step in all experiments based on cold atom research.It is also the basis for further study.It can be said that the preparation of cold atoms in the whole cold atomic correlation experiment to a decisive role.This paper is a detailed description of the preparation of sodium-cooled atoms in the experimental study of laser-induced trapping of neutral sodium atoms,which includes the design of the entire vacuum system for the laser-generated formation of the respective laser beams of neutral sodium atoms,capable of producing 589 nm The choice of the laser source,and the source of the magnetic field required for the two-dimensional magneto-optical trap,the Zeeman-slower,and the three-dimensional magneto-optical trap.Finally,it is shown that the experimental parameters are optimized for cooling the trapped sodium in a three-dimensional magnetron trap vacuum glass chamber the number of atoms to reach 108.In this paper,we first introduce some mature emerging technologies developed in cold atom and ultra-cold atoms in recent years,including optical lattice technique,Feshbach resonance technique,in-situ imaging,optical phase-locked loop,and Raman optical coupling spin State of the way of the spin-orbit-coupled ultra-cold atom gas technology.These technologies are vastly rich in cold atoms as well as ultra-cold atoms in the field of research,making more and more scientific scholars engaged in the forefront of physics to explore the physical world unknown beauty and wonderful.Then we introduce the sodium atom of the object of this study,and why we choose the sodium atom as our experimental object.We introduce the vacuum system of cooling the captured sodium atom,explain the various components of the vacuum system,and the function and function of each part.Part of the direct connection with each other,so that the sodium atoms are eventually cooled to capture the three-dimensional magneto-optical trap vacuum glass chamber,the bright spot is the sodium source in the vacuum system placed.Secondly,this paper introduces a laser system for cooling trapped sodium atoms.Our experimental method of cooling the capture of sodium atoms is the basic means of magneto-optical trap and Zeeman reducer,using a two-stage cooling method,first two-dimensional magneto-optical trap and Zeeman reducer first cooling to capture part of the sodium atoms,and then These cold source atoms are pumped through a bundle of push beams through the differential tube to the three-dimensional magnetron trap vacuum glass chamber again.At present,there is no direct generation of 589 nm diode laser on the market,and can directly produce 589 nm dye laser does not meet our experimental requirements,and ultimately we use the laser frequency doubling technology to obtain the cooling of sodium ions captured laser light source.Then in the article,the paper describes how to standardize the design of safe opening and closing lasers,the design of the experimental optical path and the setting of the frequency detuning of each laser beam used to cool the captured sodium atoms.Then we introduced the design of the bright quadrupole magnetic field in which the neutral sodium atom was captured in the experiment.We did not use the traditional design of the Helmholtz coil through a constant current to produce a stable quadrupole magnetic field,The permanent magnet group made of permanent magnets produces the magnetic field required for our experiments for two-dimensional magneto-optical traps and Zeeman reducers.This makes the entire two-dimensional magneto-optical trap and Zeeman reducer on the sodium atoms of the cooling capture device becomes more concise,to ensure the experimental results under the premise.After we introduced in the three-dimensional magneto-optical trap vacuum glass chamber to see the first time to be cooled after the capture of sodium atoms through the rational optimization of the various experimental parameters,including the Zeeman-slower cooling light frequency detuning,Zeeman-slower cooling light polarization,The frequency detuning of the twodimensional magneto-optical trap and the frequency detuning of the pushed light,and finally the number of sodium atoms captured in the vacuum chamber of the three-dimensional magnetron trap is up to 108 And can not meet the requirements of our follow-up experiment.Finally,through the summary of the full text,pointed out that the whole experiment we have achieved some of the results and experience,we need to follow the direction of the future.