Spectroscopy of the 1S0-1P0 clock transition of 87Sr in an optical lattice -: art. no. 223001

We report on the spectroscopy of the 5s(2) S-1(0)(F=9/2)-->5s5p P-3(0)(F=9/2) clock transition of Sr-87 atoms (natural linewidth of 1 mHz) trapped in a one-dimensional optical lattice. Recoilless transitions with a linewidth of 0.7 kHz as well as the vibrational structure of the lattice potential were observed. By investigating the wavelength dependence of the carrier linewidth, we determined the magic wavelength, where the light shift in the clock transition vanishes, to be 813.5+/-0.9 nm.