For comparison, Voyager 1 is almost 24.8 billion km away from Earth right now and has been traveling since 1977 (near on 50 years).
Haven’t read the article yet, but if the headline is anything to go by, very cool if it can be done.
Edit:
Just read the article. Disappointingly but unsurprisingly:
The paper defined an ideal power plan that can output 1 kW per kg of weight.
This is currently well outside the realm of possibility, with the best ion thruster power sources coming at something like 10 W per kg and even nuclear electric propulsion systems outputting 100 W per kg. Some potentially better technologies are on the horizon, but nothing tested in the literature would meet this requirement yet.