In a previous study, the researchers observed interference using a simpler set-up known as a half-loop Stern-Gerlach interferometer, in which they separated the wave packets and then allowed them to expand over time until they overlapped. In contrast, the new “full-loop” interferometer actively brings the wave packets back together, and detects interference through variations in spin population rather than a spatial fringe pattern. The researchers say that this more complex technique should make it possible to observe the interference more quickly, and without the need for high-resolution imaging.
I don't understand a lot of the terminology used here, but for me, this paragraph summarized nicely the significance of the new ability researchers have to observe interference patterns. Taken by itself, there is a lot left out here, but this intuitively makes some sense.