27 What is 'Surface Code'? (Quantum Error Correction) 2018-05-19T14:16:46.973

23 What level of "confidence" of the result from a quantum computer is possible? 2018-03-12T19:10:23.483

22 Is error correction necessary? 2018-03-14T01:32:52.570

21 Why can't there be an error correcting code with fewer than 5 qubits? 2018-11-23T12:53:11.490

20 Which quantum error correction code has the highest threshold (as proven at the time of writing this)? 2018-03-13T13:24:24.397

17 Connection between stabilizer generators and parity check matrices in the Steane code 2018-10-03T22:19:33.770

16 How does magic state distillation overhead scale compare to quantum advantages? 2018-03-19T05:50:31.297

16 Why do error correction protocols only work when the error rates are already significantly low to begin with? 2018-03-27T17:09:15.597

14 Is Gil Kalai's argument against topological quantum computers sound? 2018-04-16T10:56:52.610

12 What is the leading edge technology for creating a quantum computer with the fewest errors? 2018-03-21T00:20:54.037

12 What is the difference between "code space", "code word" and "stabilizer code"? 2018-04-17T18:44:52.797

12 What is quantum t-design (intuitive understanding)? 2018-08-22T02:19:13.523

12 What are magic states? 2020-09-07T13:24:19.980

11 What is quantum entanglement, and what role does it play in quantum error correction? 2018-04-01T09:53:46.993

11 Is the Pauli group for $n$-qubits a basis for $\mathbb{C}^{2^n\times 2^n}$? 2018-07-11T08:12:01.023

11 What is the Helstrom measurement? 2018-09-05T14:59:27.757

11 Where do we put error correction code in quantum circuit? 2018-11-06T14:45:09.577

10 Violation of the Quantum Hamming bound 2018-05-15T08:16:16.503

10 What is a Bacon-Shor code and what is its significance? 2018-06-27T23:10:34.733

10 How is computation done in a 2D surface code array? 2018-10-12T20:43:01.873

9 How could Majorana particles be used to improve quantum computers? 2018-03-29T19:15:12.063

9 What does quantum error correction code notation stand for? 2018-04-16T21:26:17.250

9 Why is the Pauli group used for stabilizers? 2018-04-17T13:42:56.093

9 How does the size of a toric code torus affect its ability to protect qubits? 2018-05-18T20:16:22.253

9 Why do we use ancilla qubits for error syndrome measurements? 2018-05-23T15:42:16.220

9 Allowed CNOT gates for IBM Q 5 quantum computer 2018-05-30T14:58:46.317

9 Are all $[[n, k, d]]$ quantum codes equivalent to additive self-orthogonal $GF(4)^n$ classical codes? 2018-06-20T15:14:25.017

9 Significance of Clifford operations from quantum error correction perspective 2018-08-16T11:12:57.027

9 Reference that explains how to read 3d topological diagrams for surface code computations 2019-01-27T08:41:09.833

9 Twirling Quantum Channels: Pauli and Clifford Twirling 2019-05-28T08:51:28.543

8 Why does the surface (quantum error correction) code have such a high threshold for errors? 2018-04-01T12:22:37.357

8 What quantum channels are considered in quantum communication, and how does this choice affect the construction of error correction codes? 2018-05-22T10:14:21.380

8 Reference on MITxPRO Applications of Quantum Computing Professional Certificate Program 2018-06-01T08:01:24.223

8 Practical Implementations of QECCs in IBM Q Experience 2018-06-05T09:59:30.530

8 Compact way of describing the set of all stabilizer groups for fixed number of physical qubits and encoded logical qubits 2018-09-10T22:06:44.073

8 How is the decoherence rate connected to the error rate? 2019-05-08T14:25:04.253

8 How to calculate the distance of stabilizer code? 2019-06-03T15:38:53.727

8 Intuition about Knill-Laflamme QEC conditions 2019-08-03T13:33:34.283

7 Intuition for Shor code failure probability 2018-04-19T16:50:05.380

7 Translation of color/toric code to a small network of solid-state spins 2018-05-07T05:30:05.307

7 Zero-distance self-dual GF(4) quantum codes and constructing k > 0 codes from them 2018-06-10T15:10:33.250

7 What does "conjugation of coordinates" mean with respect to GF(4) (quantum) codes 2018-06-11T08:34:07.303

7 What are reliable references on analytical and/or numerical studies of threshold theorems under faulty quantum error correction? 2018-07-20T18:28:00.140

7 Physical meaning of twirling in Randomized Benchmarking 2018-08-24T01:48:50.600

7 Collective measurements: importance and realization 2018-09-25T13:17:47.417

7 How does measurement calibration work? 2019-05-17T10:46:07.143

7 Entanglement-assisted hashing bound for asymmetric depolarizing channels 2019-09-30T15:10:18.837

6 Lower bound for Degenerate Codes? 2018-04-30T11:49:30.383

6 Degeneracy of Quantum Error Correction Codes 2018-05-14T10:19:31.483

6 Shor code: phase flip error 2018-07-12T19:37:40.197

6 Quantum error correction: necessary and sufficient condition 2018-07-15T07:06:20.873

6 Why can a point in anti-de Sitter space be modeled as a logical qutrit and how is its error correction done? 2019-01-28T19:16:19.923

6 In what situation are three rounds of syndrome measurement required for fault-tolerance in the surface code? 2019-03-07T10:47:21.593

6 What is the definition of Bell state on a n-qubit system? 2019-06-07T17:49:36.137

6 Error syndromes and recovery procedure in bit flip code 2019-06-07T21:39:40.613

6 2 ways to do the three qubits bit-flip code 2019-06-18T16:57:12.613

5 What set of quantum logical operations can one use to benchmark spin Hamiltonians? 2018-04-08T20:53:56.737

5 Computing with Logical Qunits 2018-07-02T19:26:24.927

5 Quantum Belief Propagation decoding 2018-08-08T14:10:53.663

5 Why is the $N$-qubit stabilizer group abelian? 2018-10-25T18:54:54.670

5 Is the common depiction of a surface code to be taken literally as a real-space image of the actual hardware? 2018-10-26T20:16:18.263

5 What is the longest quantum circuit? 2018-11-13T09:49:46.780

5 Stabilizer for quantum error correction code 2018-11-19T13:40:17.253

5 Confusion on the definition of the phase-damping channel 2018-11-26T11:40:24.430

5 Get result measurement into a circuit with Qiskit 2019-06-14T15:03:24.860

5 Knill-Laflamme condition and requirements for error correction 2019-07-30T14:35:56.333

5 Nielsen & Chuang Exercise Question on CSS code 2019-11-11T16:14:40.357

5 Why does quantum error correction work? 2020-01-06T14:04:22.253

5 Nielsen&Chuang 5-qubit quantum error-correction encoding gate 2020-10-20T08:40:31.943

5 Is there a good reason to use T-count minimization for circuits executed on current IBM open quantum systems (real hardware)? 2020-11-27T06:42:41.557

5 In quantum computation, if the fidelity is high enough to promise over 50% success rate, is quantum error-correction still needed? 2020-12-09T18:35:01.510

5 CSS Code in disguise 2021-01-06T08:09:05.173

4 How to find the fidelity between two state when one is an operator? 2018-06-01T17:06:43.663

4 topological error correction concepts 2018-07-21T15:57:50.173

4 How to deal with -LookupError: backend "ibmqx4" is not found? 2018-09-12T07:47:12.397

4 EA-Turbo simulation package 2018-09-17T10:39:51.347

4 Why does this error correcting code not work? 2018-11-03T01:56:26.787

4 Is the quantum Singleton bound compatible with the Toric Code? 2019-04-05T17:17:36.617

4 Shor's Code: Understanding how it satisfies Knill Laflamme Theorem 2019-10-18T14:57:05.257

4 Matrix Index and multiplication rules for Hermitian Pauli group products 2019-10-20T11:58:22.907

4 Where does error correction go in a quantum algorithm? 2019-11-29T20:01:19.220

4 How to implement if statement based on measurement results in qiskit? 2020-01-02T04:25:37.230

4 Logical qubit initialization for the surface code 2020-01-06T16:37:55.963

4 What kind of errors does the master equation in the Lindblad form describe, continuous errors or discrete errors? 2020-01-10T07:33:03.800

4 What is a difference between error rates and qubit/gate fidelity? 2020-06-09T22:19:25.047

4 What are generators for a "real" Clifford group? 2020-06-27T03:45:15.607

4 How to create the logical $|0_L\rangle$ state for the Steane's 7-qubit code? 2020-07-23T20:20:18.453

4 Is there a proof or example to show that a noiseless subsystem is not necessarily closed under addition? 2020-08-14T15:29:17.450

4 Why is the action of controlled-Z unaltered by exchanging target control qubits? 2020-08-15T13:56:39.123

4 How to measure syndromes in QEC 2020-10-03T21:25:17.513

4 Which codes can implement transversal non-Clifford gates 2020-11-29T17:44:31.523

4 Are applications with only polynomial speedup worth chasing after? (since error correction adds a heavy overhead) 2021-01-02T22:31:48.713

3 A question on Eastin-Knill theorem 2019-03-07T09:50:47.677

3 In error correction code why don't we imitate the Hamming code instead of the complicated Steane code? 2019-03-10T21:21:26.500

3 Estimating the depolarizing probability of depolarizing channels 2019-03-11T14:54:43.750

3 How does the actual measurement collapsing an error to an orthogonal basis look like? 2019-03-13T01:24:54.743

3 State of a system after the second qubit of a Bell state sent through a bit flip error channel 2019-05-13T20:29:00.273

3 Shor 9 qubit code — how are the observables measured and eigenvalues obtained during syndrome measurement? 2019-05-17T03:23:47.363

3 How do you implement a negative controlled gate using the regular controlled gate? 2019-06-21T10:50:02.903