First quantum simulation experiment looks beautiful, but faces a lot of questions Super fluid to Mott insulator phase transition in 3-D optical lattice Greiner M, Mandel O, Esslinger T, Hansch T 3D optical lattice W.& Bloch, Nature 415, 39-44 (2002) Quantum degenerate Bose/Fermi system Lack of a clear diagnostic of how below micro kelvin to identify phases Optical lattice provide periodical potential · Complications due to with no defects coexistence of different phases Atom-atom interaction can be described by a in the same confining potential simple s-wave scattering length Lack of thermometry of the Bose Easily tunable Hubbard Model parameters gas in the optical lattice Artificial toy models: 1D, 2D, spinor, etc
• Quantum degenerate Bose/Fermi system below micro Kelvin • Optical lattice provide periodical potential with no defects • Atom-atom interaction can be described by a simple s-wave scattering length • Easily tunable Hubbard Model parameters • Artificial toy models: 1D, 2D, spinor, etc Super fluid to Mott insulator phase transition in 3-D optical lattice Greiner M., Mandel O., Esslinger T., Hansch T. W. & Bloch I., Nature 415, 39–44 (2002). First quantum simulation experiment looks beautiful, but faces a lot of questions 3D optical lattice • Lack of a clear diagnostic of how to identify phases • Complications due to coexistence of different phases in the same confining potential • Lack of thermometry of the Bose gas in the optical lattice
Time of flight (TOF)imaging CCD
Time of flight (TOF) imaging
TOF imaging of BEC IOP BEG的相变过程 10ms 各向异性膨胀
0ms 10ms 20ms 30ms BEC的相变过程 各向异性膨胀 TOF imaging of BEC @ IOP
Problem with tof measurement T/t=0.57 0.6 0.2 60 40 0 20 2rvd 0 ruD 100 T/t=0.50 0.6 t/U=025 0 1020 Qi Zhou et al, PRL 103, 085701(2009)
Problem with TOF measurement Qi Zhou et al, PRL 103, 085701 (2009)
In-situ imaging corner stone setting experiment by Chin's group at Chicago 产殘 Absorption imaging of density profile of thin layer cold atoms in 2-D optical 4 lattice with a high numerical aperture -40040-40040-40040 Distance(um) Imaging lens. 15° Gemelke, N, Zhang, X, Hung, C.-L& Chin, Nature, 460, 995 (2009)
Gemelke, N., Zhang, X., Hung, C.-L. & Chin, Nature, 460, 995 (2009) Absorption imaging of density profile of thin layer cold atoms in 2-D optical lattice with a high numerical aperture imaging lens. In-situ imaging: corner stone setting experiment by Chin’s group at Chicago