Chinese Physics B
Superfluid to Mott-insulator transition in a one-dimensional optical lattice
Wenliang Liu, Ningxuan Zheng, Jun Jian, Li Tian, Jizhou Wu, Yuqing Li, Yongming Fu, Peng Li, V. B. Sovkov, Jie Ma, Liantuan Xiao, Suotang Jia
Abstract
Bose–Einstein condensates (BEC) of sodium atoms are transferred into one-dimensional (1D) optical lattice potentials, formed by two laser beams with a wavelength of 1064 nm, in a shallow optical trap. The phase coherence of the condensate in the lattice potential is studied by changing the lattice depth. A qualitative change in behavior of the BEC is observed at a lattice depth of ∼ 13.7 E r, where the quantum gas undergoes a transition from a superfluid state to a state that lacks well-to-well phase coherence.