Surface-sim

This package is a wrapper around Stim to simplify the construction of QEC circuits. Given a circuit, it can implement the logical equivalent under different types of noise, including circuit-level noise. It uses a code layout that helps with qubit labeling, indexing and connectivity. It also defines the detectors automatically for any sequence of logical gates.

For more information see the documentation.

Installation

This package is available in PyPI, thus it can be installed using pip install surface-sim

or alternatively, it can be installed from source using git clone git@github.com:MarcSerraPeralta/surface-sim.git pip install surface-sim/

Example

Pre-built experiment: memory experiment

``` from surfacesim.layouts import rotsurfacecode from surfacesim.models import CircuitNoiseModel from surfacesim.setups import CircuitNoiseSetup from surfacesim import Detectors from surfacesim.experiments.rotsurfacecodecss import memory_experiment

prepare the layout, model, and detectors objects

layout = rotsurfacecode(distance=3) setup = CircuitNoiseSetup() model = CircuitNoiseModel(setup, layout.qubitinds) detectors = Detectors(layout.ancqubits, frame="pre-gate")

create a memory experiment

NUMROUNDS = 10 DATAINIT = {q: 0 for q in layout.dataqubits} ROTBASIS = True # X basis MEAS_RESET = True # reset after ancilla measurements PROB = 1e-5

setup.setvarparam("prob", PROB) stimcircuit = memoryexperiment( model, layout, detectors, numrounds=NUMROUNDS, datainit=DATAINIT, rotbasis=ROTBASIS, ancreset=MEASRESET, ) ```

Arbitrary logical circuit from a given circuit

``` import stim

from surfacesim.setups import CircuitNoiseSetup from surfacesim.models import CircuitNoiseModel from surfacesim import Detectors from surfacesim.experiments import schedulefromcircuit, experimentfromschedule from surfacesim.circuitblocks.unrotsurfacecodecss import gatetoiterator from surfacesim.layouts import unrotsurfacecodes

circuit = stim.Circuit( """ R 0 1 TICK CNOT 0 1 TICK S 0 I 1 TICK S 0 H 1 TICK M 0 MX 1 """ )

layouts = unrotsurfacecodes(circuit.numqubits, distance=3) setup = CircuitNoiseSetup() model = CircuitNoiseModel.fromlayouts(setup, *layouts) detectors = Detectors.from_layouts("pre-gate", *layouts)

setup.setvarparam("prob", 1e-3)

schedule = schedulefromcircuit(circuit, layouts, gatetoiterator) stimcircuit = experimentfromschedule( schedule, model, detectors, ancreset=True ) ```

For more information and examples about surface-sim, please read the documentation.