Quantum torpedo
The quantum torpedo was a weapon developed by Starfleet to replace the standard photon torpedo. It was first developed in 2368, and deployed throughout the fleet in the beginning of 2371.
Quantum torpedoes were not completely effective against solid neutronium.
Background
The Star Trek: Deep Space Nine Technical Manual states that quantum torpedoes rely on harnessing zero-point energy, increasing their destructive power to above the maximum capable with a photon torpedo. Specifically, the zero-point initiator is activated by an uprated photon torpedo warhead at 19.5 isotons, producing a final explosive yield of 50+ isotons. Furthermore, the pattern of energy release (duration, vector, etc.) makes the blast more difficult to disperse by starship shields, increasing the tactical effectiveness beyond that of a photon torpedo even more.
According to the videogame manual for Star Trek: Starfleet Command III, the quantum torpedo, "Utilizes an eleven-dimensional spacetime membrane suspended in an ultra-clean vaccum within the projectile. The membrane is then twisted into a string and isolated from the background vaccum, resulting in the creation of a new particle, which is accompanied by the release of a tremendous amount of energy." However, this is a videogame, and probably inaccurate.
