Questions tagged [lattice-surgery]
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42 questions
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If T gates are now as expensive as CNOTs, what should be optimized?
Is there a simple circuit metric that describes the overhead of implementing a circuit with lattice surgery? If there is no such metric, does this imply that it no longer makes sense to optimize a ...
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Is there any way to efficiently construct this circuit via lattice surgery?
Consider the following circuit performed on logical qubits 1, 2, 3, 4 (encoded as a rotated surface codes) via lattice surgery:
Currently I'm implementing the CNOTs directly via grow, split, merge, ...
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How do you rotate a rotated surface code?
Given a single logical qubit encoded in a rotated surface code with X boundaries horizontally aligned and Z boundaries vertically aligned, how do you rotate it such that now the X boundaries are ...
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Why are the thresholds for the rotated surface code vs. lattice surgery different?
I am currently having trouble understanding the threshold graph for the CX-Gate implementation via lattice surgery. I have used my own package as well as the tqec package which creates ...
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How to enumerate all low-weight undetectable logical errors from a stim circuit?
I have a stim.Circuit instance that is supposed to implement a distance 6 = 7 - 11 computation. It turns out that ...
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STIM: How to define observables in a CX-Gate with lattice surgery?
I am currently implementing lattice surgery with the help of stim. My current goal is to create a package to implement a complete CNOT procedure with the help of lattice surgery. I am (in theory) done,...
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Why are there different Implementations of the CX Gate through Lattice-Surgery?
Currently, I am implementing a CX gate in STIM with the help of lattice surgery and I am a bit confused why there are multiple ways of implementing it.
In an earlier paper by Horsman in 2013 (https://...
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How does one modify the surface code cycle time in the code for "How to factor 2048 bit RSA integers with less than a million noisy qubits"?
The code in "How to factor 2048 bit RSA integers with less than a million noisy qubits" assumes a cycle time of 1 microsecond, which is too strict for neutral atoms. 1 millisecond sounds ...
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Measurements in Lattice Surgery in Rotate Surface Code
I am having problems understanding the Measurements happening during the Lattice Surgery Merge and Split operation.
I have read some papers, and I feel confused about different convention that they ...
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Approximating lattice surgery error rate using memory / stability experiments on an elongated surface code
How well can the error rate of a lattice surgery merge+split operation between two distant rotated surface codes be approximated by simulating a single elongated (asymmetric) surface code? If both ...
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Expanding the distance of a simple surface code
I am interested in this problem in the context of state injection, but I've started from a much simpler case.
Let's say I initialize a surface code of d1 = 3 in the Z-basis. I measured all stabilizers ...
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Growing the code distance in MBQC setup (e.g. RHG cube)
In "stabilizers measurement" stile of QECC, one can increase the code distance by creating additional (unentangled) qubits, and subsequently measure the stabilizers of the former code along ...
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How does one implement Hadamard gate in Pauli-based computation?
Pauli-based computation supposedly gives the full Clifford group.
For instance, the CNOT can be implemented using joint ZZ measurement and joint XX measurement and using an additional ancilla qubit.
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Lattice Surgery for Rectangular Surface Codes?
It has been shown that one can reduce the X or Z code distance for surface codes, when the noise is biased towards one type of fault. From my understanding, this is referred to as the rectangular ...
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How to measure the irregular stabilizers, as in "A Game of Surface Codes"?
I have been going through A Game of Surface Codes: Large-Scale Quantum Computing with Lattice Surgery; however, I am running into issues understanding the "irregular" stabilizers, first ...
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