4 papers
A passive self-correcting quantum memory in three dimensions
Shankar Balasubramanian, Margarita Davydova, Ting-Chun Lin
We construct a 3D Pauli stabilizer Hamiltonian whose ground state space can encode a qubit for exponential time when coupled to a bath at non-zero temperature. Our construction rec…
Universal fault tolerant quantum computation in 2D without getting tied in knots
Margarita Davydova, Andreas Bauer, Julio C. Magdalena de la Fuente +3
We show how to perform scalable fault-tolerant non-Clifford gates in two dimensions by introducing domain walls between the surface code and a non-Abelian topological code whose co…
A local automaton for the 2D toric code
Shankar Balasubramanian, Margarita Davydova, Ethan Lake
We construct a local decoder for the 2D toric code using ideas from the hierarchical classical cellular automata of Tsirelson and Gács. Our decoder is a circuit of strictly local q…
Cups and Gates I: Cohomology invariants and logical quantum operations
Nikolas P. Breuckmann, Margarita Davydova, Jens N. Eberhardt +1
We take initial steps towards a general framework for constructing logical gates in general quantum CSS codes. Viewing CSS codes as cochain complexes, we observe that cohomology in…