Extremal Magic States from Symmetric Lattices

Abstract

Magic, a key quantum resource beyond entanglement, remains poorly understood in terms of its structure and classification. In this paper, we demonstrate a striking connection between high-dimensional symmetric lattices and quantum magic states. By mapping vectors from the $E_8,B{W}_{16}$, and $E_6$ lattices into Hilbert space, we construct and classify stabiliser and maximal magic states for two-qubit, three-qubit and one-qutrit systems. In particular, this geometric approach gives closed-form lattice representatives of maximal magic states and motivates a conjecture for the number of three-qubit maximal states. In the three-qubit case, we further classify the extremal magic states according to their entanglement structure. We also show that the 45 one-qutrit maximal magic states selected by the second shell of $E_6$ split into two Clifford orbits. Our findings suggest that deep algebraic and geometric symmetries underlie the structure of extremal magic states.

Comments: 28 pages, 6 figures, 4 tables