the next version will come with plasma micro jets ejection from the cutting edge - convenient for civilian use. I'm also wandering about an array of shaped micro-charges on the edge - should be able to cut through several millimeters of steel in one move, etc. so a soldier can cut though an opponent's ballistic vest or a into an lightly armored IFV.
You can have it sharp with shaped charges array sitting a bit deeper and sideways, and new edge breaking out as side effect of shaped charges exploding, rinse and repeat, about 5 times for a regularly sized sword.
Even more interesting alternative is to have some quick blade switching machinery to switch on-the-fly between the actual blade edge and the shaped charge array and to add some feeding machinery of shaped charges into the array (and to have some stretch-shaped charges instead of the rounded ones)