We have developed a technique to produce, manipulate and trap Rb2 molecules with a single optical beam. This beam is generated by a high-power fiber amplifier (50 W of total output power) in the 1060 to 1070 nm range, which is seeded by two light sources: a sharp-band laser and a broadband superluminescent diode. The laser source is tuned to produce Rb2 molecules from an ultracold 85 Rb sample via photoassociation. The broadband spectrum vibrationally cool the molecules by optical pumping. This source is spectrally shaped in order to populate the molecules at the fundamental vibrational state = 0. The molecular sample is probed by twophoton ionization, promoted by a pulsed dye laser in the 475 to 480 nm range. By scanning the photoassociation laser frequency, we have obtained a photoassociation spectrum of the ′ = 138 state of the 0 + potential, confirming previous observations. We have also obtained two vibrational spectra of the molecules by varying the ionization laser frequency, in the presence and absence of the broadband source. The comparison between the two spectra, along with abinitio data, provides evidences that the molecules are optically pumped to the fundamental vibrational state.