Controlled directional ion emission from several fragmentation channels of CO driven by a few-cycle laser field

We explore the dissociative ionization of CO with carrier-envelope-phase (CEP) tagged few-cycle laser pulses. We observe the CEP dependence of the directional emission of Cp+ and Oq+ fragments from transient CO(p+q)+ ions, where p + q <= 3 and q <= 1. At I-0 = 3.5 x 10(14) W/cm(2), a 180 degrees phase difference between the C+ and O+ fragments from the (p = 1, q = 0) and (p = 0, q = 1) channels reflects the orientation dependence of the CO ionization. At I-0 = 1.2 x 10(15) W/cm(2), we find a similar to 35 degrees phase shift between the C2+ fragments from the (p = 2, q = 0) and (p = 2, q = 1) channels, in contrast to the 180 degrees shift previously observed between the C2+ fragment channels at I-0 = 6 x 10(14) W/cm(2) [Phys. Rev. Lett. 106, 073004 (2011)]. DOI: 10.1103/PhysRevA.86.063403