We demonstrate phase locking between two pairs of nanosecond laser pulses generated from independent sources. We achieve phase locking experimentally by separately mixing two uncorrelated dye lasers of frequencies ω 1(a) and ω1(b), with a common beam of frequency ω0, thereby generating two additional frequencies ω2(b) ≡ ω1 (a) + ω0 and ω2(a) ≡ ω1(b) + ω0. We demonstrate that there are well-defined phase relationships between any two-photon process using the ω1(a) and the ω2 (a) pair of frequencies versus any two-photon process that uses the ω1(b) and the ω2(b) pair. In particular, interference between the two identical sum frequencies ωtotal = ω1(a) + ω 2(a) and ωtotal = ω 1(b) + ω2(b), which we generate in a separate pair of mixing crystals, yields stable interference fringes with measured modulation depths of ±40%. Well-defined phase relationships are especially useful for two-photon versus two-photon coherent control experiments. In addition, the system can be used to transport, with a high degree of stability, the phase of a given input laser frequency ω0 to higher frequencies ωtotal by use of carrier lasers that need not be correlated.
|Number of pages||7|
|Journal||Journal of the Optical Society of America B: Optical Physics|
|State||Published - 1 Jan 2003|
ASJC Scopus subject areas
- Statistical and Nonlinear Physics
- Atomic and Molecular Physics, and Optics