Magic State Factory Catalog

[\![156,\,28,\,3]\!] factory

\mathrm{T}_{0}\cdot \mathrm{T}_{1}\cdot \mathrm{T}_{2}\cdot \mathrm{T}_{3}\cdot \mathrm{T}_{4}\cdot \mathrm{T}_{5}\cdot \mathrm{T}_{6}\cdot \mathrm{T}_{7}\cdot \mathrm{T}_{8}\cdot \mathrm{T}_{9}\cdot \mathrm{T}_{10}\cdot \mathrm{T}_{11}\cdot \mathrm{T}_{12}\cdot \mathrm{T}_{13}\cdot \mathrm{T}_{14}\cdot \mathrm{T}_{15}\cdot \mathrm{T}_{16}\cdot \mathrm{T}_{17}\cdot \mathrm{T}_{18}\cdot \mathrm{T}_{19}\cdot \mathrm{T}_{20}\cdot \mathrm{T}_{21}\cdot \mathrm{T}_{22}\cdot \mathrm{T}_{23}\cdot \mathrm{T}_{}\cdots

distance, proved here
d=3
error coefficient
A_{3}=676
\gamma_\rho
1.5635
V_{\mathrm{ex}}
28
wires
N=38
Clifford correction
none with T powers
found by
AI search pure T

The circuit

The 38\times156 matrix. Rows are wires and columns are rotations. A 1 means the wire takes part in the rotation, and the number beside each wire is its row weight. Scroll sideways to see every column.

  • output wires
  • check wires, measured and postselected
wire
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
out 0 (59)1·1··········11··111··1·1·1··111·1··1····1·1········1·1·····111·1·1··1·1·1·111·11·····1·1···111···1·1···1··111·1··1···1·1·······1·1·····111·1·1···11··111···
out 1 (75)1·1··········11·1111111···11·11·11··11··11···11··11···111··1111···11·····1·1·1111·····1·1·1·11111·1·····11·11·11··11·11···11··11··111···111···11······111·1·
out 2 (61)···11······11····1·1·11·······1··1···1111·1111·1·1····1·1·1·······1·11·1·111··1··11·11······1·1·1·1·······1·1··1···111·1111·1·1···1·11········1·1·11··11··1·
out 3 (47)1·1··········11··1111········1·1·1·1·····1·1········1·1······1111······1·1·1···11·····1·1···1111···········1·1·1·1····1·1·······1·1······1111······11·11····
out 4 (65)1····1·····11111·11·······11·1····1····1·1···111··1····1111··11····111·1·111··11···1111·11··11··········1111····1···1·1···111··1···111···11····11·11··11··1·
out 5 (67)··11········11··1·11··1···11·11·11··11···1·1·11··11·1·1·1·····1·1·11·····1·1·11·11···11···1··11···11····11·11·11··11··1·1·11··111·1·1·····1·1·11······111·1·
out 6 (57)···1·1·····1·1····1··1··1··1·1·1··11·1·1·1·····1·1·····11·1·111·1···111···11·····1·11·1······1··1···1····111·1··11·11·1·····1·1····111··111·1···1·1····1····
out 7 (81)1·111······111111··1·1··1··1··111111····1···1·11··1·111·1·1·11·11·111····11···11111·111·111···1·1···1····11·111111···1···1·11··1111·11··11·11·111·····1···11
out 8 (67)1·1·11······1·111·111·1·1··1··1··1···1··11··1·1··11·1111····1·1····1·1··1··1··111·11·1··111··111··1·1····1··1··1···1·11··1·1··111111····1·1····1··1····1··1·
out 9 (69)··1··1·····11··1111·····1·11·1····1····1111··111··1··1··1·1··11···11·1·1·111··1·1··111···11·11······1·1·1111····1···1111··111··1·1··11···11···11··11··11··1·
out 10 (31)1·1··········11···1·111·················1·1··········1·1····11·1···············11·····1·1····1·11·1··················1·1·········1·1··1·11·1················
out 11 (65)···1·1·····1·1··111·····1·11·1····1····111·1·111··1·1·····1··11···1·11·1·111··1··1·11·1···1·11······11··1111····1···111·1·111··11····1···11···1·1·11··11··1·
out 12 (67)····11······11··1·11···11·11·11·11··11···11·1·1··11·1·1·1·····11·1·1·····1·1·11···11·11···1··11·····1···11·11·11··11··11·1·1··111·1·1·····11·1·1······111·1·
out 13 (27)··1111·········1···11·····················1111··········1···1···················1111·····1····11·······················1111·········1··11···················
out 14 (61)1·11··1····11····1·1·11·······1·111·11·1···1·111·1····1·1·1·······1·11·1··1··1·111··11······1·1·1·1·······1·1·111·111···1·111·1···1·11········1·1·11····1···
out 15 (65)··········1111·1111·11··1·11·1····1····111····11········1·1·1·1···1111·1·111··1·····111··11·11·11···1···1111····1···111····11·······11··1·1···111·11··11··1·
out 16 (69)········1··11·111··1111···11··11··111··1··11··111·1·1·1·1·1··1··1··111·······11·····11··111···111·1·····11··11··111·1··11··111·11·1·11···1··1··11·1·····1·1·
out 17 (63)11··11·········11·11······11·11·11··11··1·1·1·1··11··11·······11··11·····1·1·111··11·····11··11·········11·11·11··11·1·1·1·1··11·11·······11··11······111·1·
out 18 (81)··1111·········1111·11··1·11·1····1····111111111··1111··1·1·1·1···1111·1·111··1·1111·····11·11·11···1···1111····1···111111111··111··11··1·1···111·11··11··1·
out 19 (67)1··111·······11··111··1·1·1··111·111·1···11·11······1·1·····111·1·1··1·1·1·····1·111··1·1···111···1·1···1··111·111·1··11·11·····1·1·····111·1·1···11··1··1··
out 20 (63)··1111·········111··1·····111··1··1111··1·1·1·1··11·1··1·····1··1·11·····1·1·11·1111·····11·1··1········11···1··1111·1·1·1·1··111··1·····1··1·11······111·1·
out 21 (27)····11······11·1·····1······················11······11··1····11···················11·11··1······11·······················11·····11··1····11·················
out 22 (67)··1··1···1··11111·111·1·1·11·11·11··11···1····1···1·1·11····1·1····1·····1·1·11·1··1·11·111··111··1·1···11·11·11··11··1····1···11·11····1·1····1······111·1·
out 23 (67)····11······11·11·111·1·1··1·111111··1···11·1·1··11·1·1·····1·1····1·1···1····1···11·11··11··111··1·1····1·111111··1··11·1·1··111·1·····1·1····1··1··11···1·
out 24 (69)1·111······11111·1·1··········1·111·11·1···111·1·1···111·····1·1··1·11·1··1··1·1111·111·11·11·1···········1·1·111·111···111·1·1··111·····1·1··1·1·11····1···
out 25 (71)··1111······11111·11······11·11·11··11···1·11·1··11·1··1······11··11·····1·1·11·1111·111111··11·········11·11·11··11··1·11·1··111··1······11··11······111·1·
out 26 (61)1······1···11··1111··11···11·1····1····1·1····1···1··1··1·1···11···111·1·111··11····11···11·11··1·1·····1111····1···1·1····1···1·1··11····11···11·11··11··1·
out 27 (59)1··1········1·1111····1·1111···11·11·1·······11··11·········11·11··1···1···1··11·1···1··111·1·····1·1··111···11·11·1······11··11········11·11··1·1·1···1··1·
check 28 (62)···11······11····1·1·11·······1·1·111····1····1··1····1·1·1··11111·1·1·1·111··1··11·11······1·1·1·1·······1·1·1·111···1····1··1···1·11···11111·1··11··11··1·
check 29 (60)··1··1·····11··11·111·1·1·11·11·1··11··1·1····1·1······1····11·1111·1···········1··111···11··111··1·1···11·11·1··11·1·1····1·1·····1····11·1111·1···········
check 30 (76)1·111······1111··1·111··11·1·1·11111·······111·1·1···1111·1·1··1····1····1·1·111111·111·1···1·111···1··1·1·1·11111······111·1·1··11111··1··1····1·····111·1·
check 31 (78)··1···1··1111····1·1·11·····1·11111·1·11···1···1·1··1·11·11111··1··11·11·11·11·111·11···111···11··1111··111·1··1111111····111··1··1·11········1·1·1··1··111·
check 32 (70)111····111·1111···········1··1···1111···111····111·111·1·············1··1·1111·111·1·1···1·1·1·1·1·11·1···1··1··1·1111·11·1··1··1···111·1·1·1·1·1····1·111·1
check 33 (76)······111·1·1·1·11·11·1·1·11··1·11·1·1111·1··11·1111··11111·11······1·11··111·1·11··11·1···11······1111·1····1111··1·1··1·1·111·····1··1·1·11··1···111·····1
check 34 (82)···1·111···11··111·11·11···111111111··11··1··1····1·1·111·11····11·11··1111······11·1·11111··1····1·111··11···111111···1·1·11··1·1··11111···1·1·····111·1111
check 35 (82)···1·1··111··1··111··1111·11·1···1111·1111·1·11111·11·····1···11·11111·1·1·111···1·111·11·1·11···1·1·11·1111··1····1·11·1·111··1·111·1···1··1·····11·····111
check 36 (76)··1·1······1·1·1··1·11111·11·1····1····1111·1·11··1·1···11111·11·11111·1·111··1·1·1·1·1···111·1··1·1·11·1111····1···1111·1·11··11·····11·1··1·····11··11··1·
check 37 (74)1····1··1····1·11·111·1·1···1·1···11·11·111···1·111···1·····1·1····1·1111·1·1··1···1··1··11··111··1·1··11111·111··1·1111···1·111··1·····1·1····1·1··11111111

The gate is read off the output rows. An output row of odd weight gives a T, a pair of output rows with odd overlap gives a CS, and an odd triple overlap gives a CCZ. The circuit is a valid factory because every such parity that touches a check row is even.

Figures of merit

inputs n156Noisy T states per run.
outputs k28
distance d3Exact, proved and witnessed here.
error coefficient A_{3}676Faults of weight 3 in the circuit shown that pass every check and damage the output. The output error is A_{3}\,p^{3} to leading order.
wires N38
checks r10
V_{\mathrm{ex}}28T states per run. CCZ counts as two.
\gamma_\rho = \log(n/V_{\mathrm{ex}})/\log d1.5635Overhead per extractable T state. Lower is better.
\gamma = \log(n/k)/\log d1.5635Overhead per output qubit.
\gamma_T = \log(n/T)/\log dnot computedOverhead per unit of T-count.
T-countnot computedMinimal T-count of the output gate. Not computable at this width.
phase-polynomial degreenot computedMinimised over changes of output basis.
effective width28Rank of the output rows modulo the check rows.

Output gate

28 T0 CS0 CCZon 28 output wires

As gates: \mathrm{T}_{0}\cdot \mathrm{T}_{1}\cdot \mathrm{T}_{2}\cdot \mathrm{T}_{3}\cdot \mathrm{T}_{4}\cdot \mathrm{T}_{5}\cdot \mathrm{T}_{6}\cdot \mathrm{T}_{7}\cdot \mathrm{T}_{8}\cdot \mathrm{T}_{9}\cdot \mathrm{T}_{10}\cdot \mathrm{T}_{11}\cdot \mathrm{T}_{12}\cdot \mathrm{T}_{13}\cdot \mathrm{T}_{14}\cdot \mathrm{T}_{15}\cdot \mathrm{T}_{16}\cdot \mathrm{T}_{17}\cdot \mathrm{T}_{18}\cdot \mathrm{T}_{19}\cdot \mathrm{T}_{20}\cdot \mathrm{T}_{21}\cdot \mathrm{T}_{22}\cdot \mathrm{T}_{23}\cdot \mathrm{T}_{24}\cdot \mathrm{T}_{25}\cdot \mathrm{T}_{26}\cdot \mathrm{T}_{27}

As monomials: 0+1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27 (output wires per term, separated by +)

This row stands for every gate that a CNOT circuit and S, Z and CZ gates on the outputs can reach from this one. They all prepare the same magic state. The wires are shown in the S_k-canonical frame.

Clifford correction

With every rotation a \mathrm{T}=\mathrm{diag}(1,e^{i\pi/4}), the rotations deposit the gate above times a diagonal Clifford. Undo it after the rotations and before the checks are measured, with 32 single-wire gates and 148 \mathrm{CZ} gates: \mathrm{S}^\dagger on output 0, \mathrm{S}^\dagger on output 1, \mathrm{Z} on output 2, \mathrm{S} on output 3, \mathrm{S}^\dagger on output 5, \mathrm{S}^\dagger on output 8, \mathrm{Z} on output 9, \mathrm{S} on output 10, \mathrm{S}^\dagger on output 12, \mathrm{S}^\dagger on output 13, \mathrm{Z} on output 14, \mathrm{Z} on output 16, \mathrm{S} on output 17, \mathrm{S}^\dagger on output 19, \mathrm{S} on output 20, \mathrm{S}^\dagger on output 21, \mathrm{S}^\dagger on output 22, \mathrm{S}^\dagger on output 23, \mathrm{Z} on output 24, \mathrm{S} on output 25, \mathrm{Z} on output 26, \mathrm{S}^\dagger on output 27, \mathrm{S} on check 28, \mathrm{Z} on check 29 and 156 more (listed below). The circuit's action is then exactly the gate above, and an error-free run passes every check with certainty.

All 180 correction gates

\mathrm{S}^\dagger on output 0, \mathrm{S}^\dagger on output 1, \mathrm{Z} on output 2, \mathrm{S} on output 3, \mathrm{S}^\dagger on output 5, \mathrm{S}^\dagger on output 8, \mathrm{Z} on output 9, \mathrm{S} on output 10, \mathrm{S}^\dagger on output 12, \mathrm{S}^\dagger on output 13, \mathrm{Z} on output 14, \mathrm{Z} on output 16, \mathrm{S} on output 17, \mathrm{S}^\dagger on output 19, \mathrm{S} on output 20, \mathrm{S}^\dagger on output 21, \mathrm{S}^\dagger on output 22, \mathrm{S}^\dagger on output 23, \mathrm{Z} on output 24, \mathrm{S} on output 25, \mathrm{Z} on output 26, \mathrm{S}^\dagger on output 27, \mathrm{S} on check 28, \mathrm{Z} on check 29, \mathrm{Z} on check 30, \mathrm{S} on check 31, \mathrm{S} on check 32, \mathrm{Z} on check 33, \mathrm{S}^\dagger on check 34, \mathrm{S}^\dagger on check 35, \mathrm{Z} on check 36, \mathrm{S}^\dagger on check 37, \mathrm{CZ} on output 0, check 36, \mathrm{CZ} on output 1, check 36, \mathrm{CZ} on output 2, output 4, \mathrm{CZ} on output 2, output 6, \mathrm{CZ} on output 2, output 7, \mathrm{CZ} on output 2, output 9, \mathrm{CZ} on output 2, output 11, \mathrm{CZ} on output 2, output 14, \mathrm{CZ} on output 2, output 15, \mathrm{CZ} on output 2, output 18, \mathrm{CZ} on output 2, output 24, \mathrm{CZ} on output 2, output 26, \mathrm{CZ} on output 2, check 28, \mathrm{CZ} on output 2, check 31, \mathrm{CZ} on output 2, check 33, \mathrm{CZ} on output 2, check 34, \mathrm{CZ} on output 2, check 35, \mathrm{CZ} on output 2, check 36, \mathrm{CZ} on output 4, output 6, \mathrm{CZ} on output 4, output 7, \mathrm{CZ} on output 4, output 9, \mathrm{CZ} on output 4, output 11, \mathrm{CZ} on output 4, output 14, \mathrm{CZ} on output 4, output 15, \mathrm{CZ} on output 4, output 18, \mathrm{CZ} on output 4, output 24, \mathrm{CZ} on output 4, output 26, \mathrm{CZ} on output 4, check 28, \mathrm{CZ} on output 4, check 31, \mathrm{CZ} on output 4, check 33, \mathrm{CZ} on output 4, check 34, \mathrm{CZ} on output 4, check 35, \mathrm{CZ} on output 5, check 36, \mathrm{CZ} on output 6, output 7, \mathrm{CZ} on output 6, output 9, \mathrm{CZ} on output 6, output 11, \mathrm{CZ} on output 6, output 14, \mathrm{CZ} on output 6, output 15, \mathrm{CZ} on output 6, output 18, \mathrm{CZ} on output 6, output 24, \mathrm{CZ} on output 6, output 26, \mathrm{CZ} on output 6, check 28, \mathrm{CZ} on output 6, check 31, \mathrm{CZ} on output 6, check 33, \mathrm{CZ} on output 6, check 34, \mathrm{CZ} on output 6, check 35, \mathrm{CZ} on output 7, output 9, \mathrm{CZ} on output 7, output 11, \mathrm{CZ} on output 7, output 14, \mathrm{CZ} on output 7, output 15, \mathrm{CZ} on output 7, output 18, \mathrm{CZ} on output 7, output 24, \mathrm{CZ} on output 7, output 26, \mathrm{CZ} on output 7, check 28, \mathrm{CZ} on output 7, check 31, \mathrm{CZ} on output 7, check 33, \mathrm{CZ} on output 7, check 34, \mathrm{CZ} on output 7, check 35, \mathrm{CZ} on output 8, check 36, \mathrm{CZ} on output 9, output 11, \mathrm{CZ} on output 9, output 14, \mathrm{CZ} on output 9, output 15, \mathrm{CZ} on output 9, output 18, \mathrm{CZ} on output 9, output 24, \mathrm{CZ} on output 9, output 26, \mathrm{CZ} on output 9, check 28, \mathrm{CZ} on output 9, check 31, \mathrm{CZ} on output 9, check 33, \mathrm{CZ} on output 9, check 34, \mathrm{CZ} on output 9, check 35, \mathrm{CZ} on output 9, check 36, \mathrm{CZ} on output 11, output 14, \mathrm{CZ} on output 11, output 15, \mathrm{CZ} on output 11, output 18, \mathrm{CZ} on output 11, output 24, \mathrm{CZ} on output 11, output 26, \mathrm{CZ} on output 11, check 28, \mathrm{CZ} on output 11, check 31, \mathrm{CZ} on output 11, check 33, \mathrm{CZ} on output 11, check 34, \mathrm{CZ} on output 11, check 35, \mathrm{CZ} on output 12, check 36, \mathrm{CZ} on output 13, check 36, \mathrm{CZ} on output 14, output 15, \mathrm{CZ} on output 14, output 18, \mathrm{CZ} on output 14, output 24, \mathrm{CZ} on output 14, output 26, \mathrm{CZ} on output 14, check 28, \mathrm{CZ} on output 14, check 31, \mathrm{CZ} on output 14, check 33, \mathrm{CZ} on output 14, check 34, \mathrm{CZ} on output 14, check 35, \mathrm{CZ} on output 14, check 36, \mathrm{CZ} on output 15, output 18, \mathrm{CZ} on output 15, output 24, \mathrm{CZ} on output 15, output 26, \mathrm{CZ} on output 15, check 28, \mathrm{CZ} on output 15, check 31, \mathrm{CZ} on output 15, check 33, \mathrm{CZ} on output 15, check 34, \mathrm{CZ} on output 15, check 35, \mathrm{CZ} on output 16, check 32, \mathrm{CZ} on output 16, check 33, \mathrm{CZ} on output 16, check 37, \mathrm{CZ} on output 18, output 24, \mathrm{CZ} on output 18, output 26, \mathrm{CZ} on output 18, check 28, \mathrm{CZ} on output 18, check 31, \mathrm{CZ} on output 18, check 33, \mathrm{CZ} on output 18, check 34, \mathrm{CZ} on output 18, check 35, \mathrm{CZ} on output 19, check 36, \mathrm{CZ} on output 21, check 36, \mathrm{CZ} on output 22, check 36, \mathrm{CZ} on output 23, check 36, \mathrm{CZ} on output 24, output 26, \mathrm{CZ} on output 24, check 28, \mathrm{CZ} on output 24, check 31, \mathrm{CZ} on output 24, check 33, \mathrm{CZ} on output 24, check 34, \mathrm{CZ} on output 24, check 35, \mathrm{CZ} on output 24, check 36, \mathrm{CZ} on output 26, check 28, \mathrm{CZ} on output 26, check 31, \mathrm{CZ} on output 26, check 33, \mathrm{CZ} on output 26, check 34, \mathrm{CZ} on output 26, check 35, \mathrm{CZ} on output 26, check 36, \mathrm{CZ} on output 27, check 36, \mathrm{CZ} on check 28, check 31, \mathrm{CZ} on check 28, check 33, \mathrm{CZ} on check 28, check 34, \mathrm{CZ} on check 28, check 35, \mathrm{CZ} on check 28, check 36, \mathrm{CZ} on check 29, check 36, \mathrm{CZ} on check 30, check 36, \mathrm{CZ} on check 31, check 33, \mathrm{CZ} on check 31, check 34, \mathrm{CZ} on check 31, check 35, \mathrm{CZ} on check 31, check 36, \mathrm{CZ} on check 32, check 33, \mathrm{CZ} on check 32, check 37, \mathrm{CZ} on check 33, check 34, \mathrm{CZ} on check 33, check 35, \mathrm{CZ} on check 33, check 36, \mathrm{CZ} on check 33, check 37, \mathrm{CZ} on check 34, check 35, \mathrm{CZ} on check 36, check 37

Or no Clifford gate at all: run \mathrm{T}^3 on rotations 1, 10, 24, 28, 37, 39, 42, 44, 45, 47, 50, 54, 56, 59, 61, 62, 64, 66, 67, 68, 80, 83, 84, 85 and 30 more (listed below); \mathrm{T}^5 on rotations 4, 8, 9, 17, 41, 82; \mathrm{T}^\dagger on rotations 0, 3, 6, 16, 20, 21, 26, 27, 29, 81, and \mathrm{T} on the rest. A power of \mathrm{T} costs one magic state, like \mathrm{T} itself. For a code this is a transversal \mathrm{T} gate, \mathrm{T}^j on each qubit.

All 54 rotations at T³

1, 10, 24, 28, 37, 39, 42, 44, 45, 47, 50, 54, 56, 59, 61, 62, 64, 66, 67, 68, 80, 83, 84, 85, 91, 93, 96, 100, 102, 103, 104, 109, 111, 113, 114, 115, 116, 117, 121, 126, 127, 128, 132, 135, 136, 137, 141, 142, 144, 148, 152, 153, 154, 155

Rotations are numbered by matrix column, from 0. The correction comes from the columns by the weight expansion of Bravyi and Haah (2012). verify_catalog.py re-derives it, checks the corrected circuit's phase input by input against the gate, and on small circuits simulates it gate by gate.

Convert the output with CNOT and S

A CNOT circuit on the outputs, followed by S, Z and CZ gates, turns this factory's gate into other gates that prepare the same magic state. Type a target gate to check whether it is reachable. If it is, you get the circuit, checked on every basis state.

Or list every gate it reaches. The list is built in your browser and saved as a text file, one gate per line.

Python code that writes the same list
import json, urllib.request

NAMES = {1: "T", 2: "CS", 3: "CCZ"}


def equivalent_gates(k, terms, limit=1_000_000):
    """Every gate a CNOT circuit and S, Z, CZ gates reach from this one.

    A gate is its set of terms mod Clifford: {a} is T, {a,b} is CS and
    {a,b,c} is CCZ on those outputs. CNOT c->t sends x_t to
    x_c + x_t - 2 x_c x_t, so a term on t but not c adds the term with t
    replaced by c, and, below CCZ, the term with c added.
    """
    start = frozenset(frozenset(m) for m in terms)
    seen, queue = {start}, [start]
    for gate in queue:
        for c in range(k):
            for t in range(k):
                if c == t:
                    continue
                new = set(gate)
                for m in gate:
                    if t in m and c not in m:
                        new ^= {(m - {t}) | {c}}
                        if len(m) < 3:
                            new ^= {m | {c}}
                new = frozenset(new)
                if new not in seen:
                    seen.add(new)
                    queue.append(new)
                    if len(seen) > limit:
                        raise RuntimeError(f"more than {limit} equivalent gates")
    return seen


def name(gate, k):
    sep = "," if k > 10 else ""
    terms = sorted((sorted(m) for m in gate), key=lambda m: (len(m), m))
    return "·".join(NAMES[len(m)] + sep.join(map(str, m)) for m in terms) or "I"


url = "https://shubhamj810.github.io/magic-state-factory-repo/data/factories/156.28.3.a.json"
record = json.load(urllib.request.urlopen(url))
k = record["parameters"]["k"]
gates = equivalent_gates(k, record["gate"]["monomials"])
lines = sorted(name(g, k) for g in gates)
print(len(lines), "equivalent gates")
with open("equivalent-gates-156.28.3.a.txt", "w") as out:
    out.write("\n".join(lines) + "\n")

Distance

d=3, exact. No fault of weight below 3 is both undetectable and damaging. One of weight 3 is.

Exactly 676 faults of weight 3 are undetectable and damaging, so A_{3}=676. If each rotation fails independently with probability p, an accepted run has a damaged output with probability A_{3}\,p^{3}+O(p^{4}).

A damaging fault of weight 3 sits on columns [0,1,103].

A fault is a set of faulty columns. It is undetectable when their check parts cancel, and damaging when their output parts do not.

Original source

S. P. Jain, A. Wills, and S. Singh, "Symmetry and AI-assisted discovery of magic-state factories," arXiv:2610.06535 (2026). arxiv.org/abs/2610.06535

Provenance

a paired-column contraction of an existing triorthogonal code, in the pure-T distillation-exponent release (gamma = log(n/k)/log d, n < 1000); a verified witness, not a maximum -- only the release's own frontier points are the lowest gamma it knows

Found by: AI search (gamma frontier): contraction of an existing code

Discovery: AI search

1 recorded source
[
 {
  "regime": "AI search (gamma frontier): contraction of an existing code",
  "file": "gamma_frontier_release/protocols/paired_column_contraction_158_28_3_ae811a8b250b.json",
  "label": "paired_column_contraction_158_28_3_ae811a8b250b",
  "N": 38,
  "d": 3,
  "d_is_exact": true,
  "origin": "Existing triorthogonal code with physical paired-column contraction",
  "provenance": "gamma frontier release record paired_column_contraction_158_28_3_ae811a8b250b (source catalogue id paired_column_contraction_158_28_3_ae811a8b250b); construction: Existing triorthogonal code with physical paired-column contraction; matrix ae811a8b250bde21...; the release states d=3 (exact), gamma=1.5750693312829973 (exact); the release matrix has 158 columns of which 2 are a repeated pair -- equal columns cancel to a diagonal Clifford and deposit nothing, so they are deleted here and this circuit is the reduced one, with 156 injections for the same gate and distance",
  "notes": "matrix gamma_frontier_release/matrices/ae811a8b250bde210d743f4144b516a709296d59b9911c4e7a03688bc609cde8.matrix"
 }
]

Use it in code

Load this factory and re-derive every number from its circuit with the catalogue's own verifier.

# git clone https://github.com/shubhamj810/magic-state-factory-repo
# cd magic-state-factory-repo/master_catalog
import json, urllib.request
import verify_catalog as VC

url = "https://shubhamj810.github.io/magic-state-factory-repo/data/factories/156.28.3.a.json"
record = json.load(urllib.request.urlopen(url))
columns = record["circuit"]["columns"]
k, N = record["parameters"]["k"], record["parameters"]["N"]

facts, problems = VC.derive(columns, k, N)    # gate, T-count, degree, ...
distance = VC.measure_distance(columns, k, N)  # exhaustive fault search
print(facts["gate_human"], distance["d_exact"] or distance["d_at_least"],
      problems or "verified")

Raw record

Show the JSON this page is built from

Source: master_catalog.json, factories[781].