Equation 14 · Part 2 · Error Correction Is the Whole Problem in Quantum Computing
Symbol d^2
What this part means
The square of d: multiply d by itself.
Its job in the formula
is one of the signed contributions combined to compute the quantity on the left.
Full expression→Symbol d^2→Article meaning
The passage around this formula
Distance d is the weight of the smallest undetectable logical error. A distance- d code corrects up to (d-1)/2 errors. For the planar surface code in its standard rotated layout, the physical cost of one logical qubit is . counting data and measure qubits together. A distance-7 patch therefore occupies ninety-seven physical qubits, and that is a memory holding one logical qubit, doing nothing else. It performs no gate, produces no non-Clifford operation, and reserves no routing space.
Learn the underlying idea
An exponent tells how a base is used in multiplication. In x³, x is the base and 3 is the exponent: x³ = x × x × x.
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See this notation across published equations →
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