Temporal coherence of high-order harmonics

The generation of high-order harmonics in strong laser fields has been studied for several years and considerable progress has been made in the understanding of the physics involved. In different laboratories around the world, scientists are now beginning to explore the use of the harmonic radiation in novel applications in the extreme ultraviolet spectral region (XUV). In some applications, the lack of information regarding the coherence properties of the harmonic radiation is a restricting factor. We here present experimental results from an interference experiment, illustrating the potentials of harmonic radiation in applications requiring temporally coherent radiation in the XUV region.