Aluminium is used for power lines, but that's working at very high voltages and it's a compromise made due to weight issue stringing copper or all-steel lines between pylons.
There's no way round the simple physics that copper has a lower resistance than aluminium. Low resistance is what you want when transporting the low voltage (<36V) high current (in relative terms) power signals for speakers. Those companies with a vested interest in selling "magic" cables can waffle all they like and produce pseudo-scientific looking "research" that supports their cause, but there's no getting around the fact that the current in the wire is inversely proportional to the cross section of the conductor and proportionately influenced by the resistance of the metal able and the length of that conductor. Skin effect (if mentioned) is only a factor at very high frequencies far in excess of the audio spectrum, and it takes something thicker than a few microns of copper flash to be a useful conductor at those frequencies.
As for data cable, once again the answer is simple. TTBOMK there's no certified cable that meets the standards for Cat 5e or Cat 6/6e or Cat 7 that is anything but pure copper.
For aerial cable and coax in general, cables with an aluminium braid have poorer noise rejection characteristics than those with a decent copper braid.
If you'd like to post a link to the research paper then I'm pretty sure we'd be interested in looking in to the claims.
