Janus' suggestion is pretty good. Despite being an extra element a trailing external link icon will look lighter and more balanced than underlining. You could even use a version with the arrow only, no square, to make it cleaner.
You could change the color, although it's almost as disruptive as underlining the names.
You can also use italics as you said. Yes, it decreases legibility, particularly in less than ideal reading settings like mine¹. It's not a long text though, it's just a couple of words, and this font family has beautiful italics.
I don't know what are the conventions in your field, but it'd be nice to add a "Co-authors" before the names. That by itself will add a little emphasis to their names.
¹You can see how text is thinner in my screenshots. That could be a concern given the size of the text. In cases like this the text tends to look worse when you use dark colors, more jagged and less legible. You may not want to make the names darker and italic at the same time.
Related to the page presentation but not the question itself: Your statement about ResearchGate is worded in a roundabout and slightly negative way. It's hard to figure the point of the sentence until finishing it. It happens because you're accidentally emphasizing the lack of new publications on your publications page when you're actually trying to point the visitor towards you latest publications.
You could rephrase it as "You can find my latest articles at ResearchGate.", "Visit ResearchGate to keep up to date with my latest work." or anything in the same vein.
Also, is the page literally "under construction"? Or is it being constantly updated to include your latest publications? The page looks pretty functional to me. Unless it's lacking some vital functionality you can drop this statement, it disrupts the flow and isn't the best practice to point out a missing feature. If it's referring to constant updates you can reword and merge it with the ResearchGate paragraph, or just drop it as well because it's implicit it's updated with new information: It's a timeline.