We construct a primitive gate set for the digital quantum simulation of the 48-element binary octahedral ( BO ) group. This non-Abelian discrete group better approximates S U ( 2 ) lattice gauge theory than previous work on the binary tetrahedral group at the cost of one additional qubit—for a total of six—per gauge link. The necessary primitives are the inversion gate, the group multiplication gate, the trace gate, and the BO Fourier transform. Published by the American Physical Society 2024
We describe the simulation of dihedral gauge theories on digital quantum computers. The non-Abelian discrete gauge group
DN---the dihedral group---serves as an approximation to $U(1)\ifmmode\times\else\texttimes\fi{}{\mathbb{Z}}_{2}$ lattice gauge theory. In order to carry out such a lattice simulation, we detail the construction of efficient quantum circuits to realize basic primitives including the non-Abelian Fourier transform over
DN, the trace operation, and the group multiplication and inversion operations. For each case the required quantum resources scale linearly or as low-degree polynomials in
n=logN. We experimentally benchmark our gates on the Rigetti Aspen-9 quantum processor for the case of
D4. The estimated fidelity of all
D4 gates was found to exceed 80%.
We construct a primitive gate set for the digital quantum simulation of a discrete subgroup of
SU(3): the 216-element
Σ(72×3). The necessary primitives are the inversion gate, the group multiplication gate, the trace gate, and the group Fourier transform, for which we provide qubit decompositions. The resulting fault-tolerant T gate costs for a fiducial calculation of shear viscosity would require about
1012 T gates which compares favorably to other modern estimates.
We construct the primitive gate set for the digital quantum simulation of the 108-element Σ ( 36 × 3 ) group. This is the first time a non-Abelian crystal-like subgroup of S U ( 3 ) has been constructed for quantum simulation. The gauge link registers and necessary primitives—the inversion gate, the group multiplication gate, the trace gate, and the Σ ( 36 × 3 ) Fourier transform—are presented for both an eight-qubit encoding and a heterogeneous three-qutrit plus two-qubit register. For the latter, a specialized compiler was developed for decomposing arbitrary unitaries onto this architecture. Published by the American Physical Society 2024
Elementary Quantum Gates from Lie Group Embeddings in
U(2n): Geometry, Universality, and Discretization
In the standard circuit model, elementary gates are defined relative to a chosen tensor factorization and are therefore extrinsic to the ambient group
U(2n). Writing
N=2n, we introduce an \emph{intrinsic descriptor layer} in
U(N) by declaring as primitive the motions inside faithful embedded copies of
SU(2) (phase-free), together with a phase-inclusive
U(2) variant. We describe the embedding landscape $\Emb(SU(2),U(N))$ as a finite union of
U(N)-homogeneous strata indexed by isotypic multiplicities, with stabilizers given by centralizers, and we isolate a canonical \emph{two-level sector} parameterized by $\Gr_2(\C^N)$ up to a
PSU(2) gauge. Equipping
U(N) with the Hilbert--Schmidt bi-invariant metric, each embedded subgroup is totally geodesic, yielding a variational characterization of elementary motions via minimal-norm logarithms. On the constructive side, we prove phase-free universality in
SU(N) from two-level primitives using QR/Givens factorizations together with explicit diagonal generation, and we obtain full universality in
U(N) by explicit abelian phase bookkeeping (equivalently, via the
U(2) two-level dictionary). Finally, we formalize a modular finite-alphabet compilation interface: any approximation routine in
SU(2) (e.g.\ Solovay--Kitaev) can be lifted through two-level embeddings to yield
U(N)-level synthesis with global operator-norm error control.
We describe the simulation of dihedral gauge theories on digital quantum computers. The nonabelian discrete gauge group
DN -- the dihedral group -- serves as an approximation to
U(1)×Z2 lattice gauge theory. In order to carry out such a lattice simulation, we detail the construction of efficient quantum circuits to realize basic primitives including the nonabelian Fourier transform over
DN, the trace operation, and the group multiplication and inversion operations. For each case the required quantum resources scale linearly or as low-degree polynomials in
n=logN. We experimentally benchmark our gates on the Rigetti Aspen-9 quantum processor for the case of
D4. The fidelity of all
D4 gates was found to exceed
80%.