It's nvme. The GEOM disks (which are what you want to use) show up as /dev/nvd#.

thus spoke the manual nvme(4): "The nvme driver creates controller device nodes in the format /dev/nvmeX and namespace device nodes in the format /dev/nvmeXnsY."

it's been a while since i've had access to nvme gear but it "just worked" at the time - although my use case was for a a daemon that accessed the block device directly to do its own horrible things to it.