Compare Papers

Paper 1

Sparse Quantum Codes from Quantum Circuits

Dave Bacon, Steven T. Flammia, Aram W. Harrow, Jonathan Shi

Year
2014
Journal
arXiv preprint
DOI
arXiv:1411.3334
arXiv
1411.3334

We describe a general method for turning quantum circuits into sparse quantum subsystem codes. The idea is to turn each circuit element into a set of low-weight gauge generators that enforce the input-output relations of that circuit element. Using this prescription, we can map an arbitrary stabilizer code into a new subsystem code with the same distance and number of encoded qubits but where all the generators have constant weight, at the cost of adding some ancilla qubits. With an additional overhead of ancilla qubits, the new code can also be made spatially local. Applying our construction to certain concatenated stabilizer codes yields families of subsystem codes with constant-weight generators and with minimum distance $d = n^{1-ε}$, where $ε= O(1/\sqrt{\log n})$. For spatially local codes in $D$ dimensions we nearly saturate a bound due to Bravyi and Terhal and achieve $d = n^{1-ε-1/D}$. Previously the best code distance achievable with constant-weight generators in any dimension, due to Freedman, Meyer and Luo, was $O(\sqrt{n\log n})$ for a stabilizer code.

Open paper

Paper 2

Proceedings 9th Workshop on Quantum Physics and Logic

Ross Duncan, Prakash Panangaden

Year
2014
Journal
arXiv preprint
DOI
arXiv:1407.8427
arXiv
1407.8427

This volume contains the proceedings of the ninth workshop on Quantum Physics and Logic (QPL2012) which took place in Brussels from the 10th to the 12th of October 2012. QPL2012 brought together researchers working on mathematical foundations of quantum physics, quantum computing, and spatio-temporal causal structures. The particular focus was on the use of logical tools, ordered algebraic and category-theoretic structures, formal languages, semantical techniques, and other computer science methods for the study of physical behaviour in general.

Open paper