activity
20242026
collaborators

11 papers

quant-ph2026

Optimal Decoding with the Worm

Zac Tobias, Nikolas P. Breuckmann, Benedikt Placke

We propose a new decoder for "matchable'' qLDPC codes that uses a Markov Chain Monte Carlo algorithm - called the worm algorithm - to approximately compute the probabilities of log…

quant-ph2026

Copy-cup Gates in Tensor Products of Group Algebra Codes

Ryan Tiew, Nikolas P. Breuckmann

We determine conditions on classical group algebra codes so that they have pre-orientation for cup products and copy-cup gates. This defines quantum codes that have constant-depth…

quant-ph2025

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…

quant-ph2025

Logical Operators and Derived Automorphisms of Tile Codes

Nikolas P. Breuckmann, Shin Ho Choe, Jens Niklas Eberhardt +2

The recently introduced tile codes are a promising alternative to surface codes, combining two-dimensional locality with higher encoding efficiency. While surface codes are well un…

cond-mat.stat-mech2025

Expansion creates spin-glass order in finite-connectivity models: a rigorous and intuitive approach from the theory of LDPC codes

Benedikt Placke, Grace M. Sommers, Nikolas P. Breuckmann +2

Complex free-energy landscapes with many local minima separated by large barriers are believed to underlie glassy behavior across diverse physical systems. This is the heuristic pi…

quant-ph2025

Tile Codes: High-Efficiency Quantum Codes on a Lattice with Boundary

Vincent Steffan, Shin Ho Choe, Nikolas P. Breuckmann +2

We introduce tile codes, a simple yet powerful way of constructing quantum codes that are local on a planar 2D-lattice. Tile codes generalize the usual surface code by allowing for…