Struct RotatedSurfaceCode 

pub struct RotatedSurfaceCode {
    pub distance: usize,
    pub data_qubits: Vec<(usize, usize)>,
    pub x_ancillas: Vec<(usize, usize)>,
    pub z_ancillas: Vec<(usize, usize)>,
}

A rotated planar surface code of distance d.

See the module-level documentation for the layout convention.

Fields

distance: usize

Code distance.

data_qubits: Vec<(usize, usize)>

Data qubit coordinates (row, col).

x_ancillas: Vec<(usize, usize)>

X-ancilla positions stored as (2*row+1, 2*col+1) in double-integer coords, plus boundary half-plaquettes stored with a sentinel value.

z_ancillas: Vec<(usize, usize)>

Z-ancilla positions (same encoding).

Implementations

impl RotatedSurfaceCode

pub fn new(d: usize) -> Self

Construct a d × d rotated planar surface code.

Panics

Panics if d < 2.

pub fn n_data_qubits(&self) -> usize

Number of physical data qubits = d².

pub fn n_k_d(&self) -> (usize, usize, usize)

Code parameters: returns (n, k, d) = (d², 1, d).

pub fn x_stabilizers(&self) -> Vec<Vec<usize>>

X stabilizers: each as a sorted list of data qubit indices.

Weight-4 for interior plaquettes, weight-2 for boundary half-plaquettes.

pub fn z_stabilizers(&self) -> Vec<Vec<usize>>

Z stabilizers: each as a sorted list of data qubit indices.

pub fn logical_x_qubits(&self) -> Vec<usize>

Logical X operator: left column of data qubits, indices [0, d, 2d, ...].

In the rotated planar surface code, X-type errors are corrected by Z-stabilizers whose boundaries are on the left and right edges. A vertical chain of X along the left column commutes with all stabilizers and anticommutes with the logical Z (top row) at qubit 0.

pub fn logical_z_qubits(&self) -> Vec<usize>

Logical Z operator: top row of data qubits, indices [0, 1, ..., d-1].

In the rotated planar surface code, Z-type errors are corrected by X-stabilizers whose boundaries are on the top and bottom edges. A horizontal chain of Z along the top row commutes with all stabilizers and anticommutes with the logical X (left column) at qubit 0.

pub fn logical_x_operator(&self) -> PauliString

Build a PauliString for the logical X operator.

pub fn logical_z_operator(&self) -> PauliString

Build a PauliString for the logical Z operator.

pub fn syndrome(&self, error: &PauliString) -> QuantRS2Result<Vec<bool>>

Compute the syndrome vector for a given Pauli error.

Returns [x_syndromes..., z_syndromes...].

• x_syndrome[i] = true if error anticommutes with X-stabilizer i (Z or Y error on support).
• z_syndrome[i] = true if error anticommutes with Z-stabilizer i (X or Y error on support).

pub fn qubit_coords(&self, idx: usize) -> Option<(usize, usize)>

Compute (row, col) coordinates of a data qubit from its linear index.

Trait Implementations

impl Clone for RotatedSurfaceCode

fn clone(&self) -> RotatedSurfaceCode

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for RotatedSurfaceCode

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.