All-optical Storage Ring For Cold Molecules Using A Hollow Laser Beam

Hollow laser beams have some important applications in atomic and molecular optics, laser optics, light information processing, material science, and biomedicine due to it's a series of unique physical characteristics. The studies on the generation of hollow laser beams and their applications have obtained fast development. In this thesis, firstly, the principle to generate hollow laser beams and their experimental results and recent progress are briefly introduced and reviewed.Secondly, we proposed a new all-optical storage-ring scheme to trap cold molecules using a red-detuned hollow laser beam, and perform the corresponding theoretical research and simulate the dynamic process of cold I2 molecules in the optical storage ring by using Monte-Carlo method. Unfortunately, we find that the maximum intensity of the focused hollow beam in the focal plane of the circular cylindrical lens and its optical potential is not enough to trap cold I2 molecules, so we improve our optical system by using so-called cavity enhance technology. We calculate the intensity distribution of the focused hollow beam around the focal plate in the cavity and its optical potential for I2 molecules, and find that the enhanced optical potential is enough for trapping cold I2 molecules. Also, the dynamic process of cold 12 molecules in the optical storage ring is simulated using Monte-Carlo method, and the results show that cold I2 molecular can be stored and traveled by multiple circles successfully.Additionally, we propose another new all-optical storage-ring scheme to trap cold molecules using a red-detuned ring-shaped diffraction light from a circular slit on a chip, and perform the corresponding theoretical research. Analogously, according to the basic principle of diffraction optics, we calculate the intensity distribution of the ring-shaped three-dimensional optical trap on the chip and its optical potential for cold I2 molecules, and find that the optical potential is relatively low, and can only be used to trap colder molecules with a temperature of about 1μK.Finally, the main researches and their results in this thesis are summarized, and an outlook about the further study of all-optical storage ring for cold molecules is given.