Abstract
Introducing an anisotropic and long-range interaction into a quantum degenerate gas is an essential ingredient for researches in strongly-correlated system [1]. Therefore, along with polar molecules and Rydberg atoms, quantum simulator with dipolar lanthanide atoms attract many attentions from the researchers due to its distinctive long range dipole- dipole interaction(DDI) which alkali atoms don’t have. Experiments including extended Bose Hubbard model [2], quantum droplet [3, 4], and supersolid phase [5, 6, 7] have been actively studied with the quantum degenerate gas made by lanthanide atoms. Also owing to its narrow linewidth transition, erbium in the narrow linewidth MOT can be directly transferred to the ODT.
Despite of these beneficial features in lanthanide atoms, creation of the degenerate lan- thanide atoms is not straightforward as expected. The high melting point of lanthanide atoms requires the high temperature oven resulting in the necessity of large slowing or cooling power. Also, the large cooling power requires large science chamber for displac- ing the trapped atom away from the slowing beams, otherwise slowing beam induces the heating which is detrimental to the cold atoms. The large science chamber is not favorable for implementing a high resolution objective lens. The single site resolved imaging for the optical lattice is very powerful tool for revealing complicated spatial correlations between particles. Especially, with the long-range DDI, non-local quantum correlations and hidden order parameter can be studied.
In this thesis, the new apparatus for dipolar quantum simulation is introduced. The new apparatus is advantageous to the study on dipolar quantum simulation with high res- olution imaging. Instead of requiring larger science chamber, we implement additional slowing beams at an angle with respect to the conventional Zeeman slower. Also, we introduce the active-control of injection locking setup for efficiently increasing the optical power budget in the lab. The experimental observations of the superradiance with dipolar BEC is presented. By means of changing direction of external magnetic field, we observe the tunable asymmetry in the superradiant scattered condensates. Although the asymmetry in the symmetry have been reported, the asymmetry presented in this thesis is believed to be different from previously observed asymmetry. It is not explained in a straightforward way by the models readily explaining previous asymmetries. Also, the future perspective with 2D dipolar gas is discussed. The accordion lattice traps the dipolar BEC in 2D.
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