Spin

class Spin(dimension, name, qubit_subspace, gyromagnetic_ratio, zero_field_splitting=0.0, local_quasistatic_noise=None)

Represent a spin.

Initialize a spin.

Parameters:

dimension (int) – Dimension, must be 2 for spin-1/2, 3 for spin-1, and so on.
name (str) – Name of the spin.
qubit_subspace (Tuple[float, float]) – The quantum numbers that defines the qubit subspace.
gyromagnetic_ratio (float) – Gyromagnetic ratio of the spin (in \(\text{MHz}/\text{T}\)).
zero_field_splitting (float) – Zero-field splitting (or quadrupole moment) of the spin (in \(\text{MHz}\)).
local_quasistatic_noise (Components1D | None) – Local-quasistatic noise components of the spin (in \(\text{MHz}\)).

Raises:

SimphonyError – If an invalid dimension or qubit subspace is provided.

Hint

For example, one can define an NV electron spin as:

spin = Spin(
    dimension = 3,
    name = 'NV-e',
    qubit_subspace = (0, -1),
    gyromagnetic_ratio = 28020, # MHz
    zero_field_splitting = 2880, # MHz
    local_quasistatic_noise = [0, 0, 1] # MHz
)

Attributes

`dimension`	Dimension, it is 2 for spin-1/2, 3 for spin-1, and so on.
`gyromagnetic_ratio`	Gyromagnetic ratio of the spin (in \(\text{MHz}/\text{T}\)).
`local_quasistatic_noise`	The local quasistatic noise components (in \(\text{MHz}\)).
`name`	Name of the spin.
`operator`	Spin operator.
`operator_qubit_subspace`	Pauli operators defined on the qubit subspace.
`quantum_nums`	Quantum numbers corresponding to spin operator.
`qubit_subspace`	Qubit subspace that is defined by a two-length subset of the `quantum_nums`.
`rotating_frame_frequency`	Rotating frame frequency corresponding to spin.
`virtual_phase`	Virtual z-phase corresponding to spin.
`zero_field_splitting`	Zero-field splitting (or quadrupole moment) (in \(\text{MHz}\)).