Gates¶

QuantSDK provides 50+ quantum gate classes covering single-qubit, two-qubit, three-qubit, and special operations.

Gate Hierarchy¶

All gates inherit from the Gate base class:

Gate (base)
├── Single-Qubit Gates
│   ├── HGate, XGate, YGate, ZGate, IGate
│   ├── SGate, SdgGate, TGate, TdgGate
│   ├── SXGate, SXdgGate
│   ├── RXGate, RYGate, RZGate, RGate
│   ├── PhaseGate, U1Gate, U2Gate, U3Gate
│   └── Reset
├── Two-Qubit Gates
│   ├── CXGate, CYGate, CZGate, CHGate
│   ├── CSGate, CSdgGate, CSXGate
│   ├── CRXGate, CRYGate, CRZGate, CPhaseGate
│   ├── CU1Gate, CU3Gate
│   ├── SwapGate, iSwapGate, DCXGate, ECRGate
│   └── RZZGate, RXXGate, RYYGate, RZXGate
├── Three-Qubit Gates
│   ├── ToffoliGate (CCX)
│   ├── CCZGate
│   └── FredkinGate (CSWAP)
└── Special Operations
    ├── Measure
    └── Barrier

Quick Reference Table¶

Gate	Class	Qubits	Parameters	Description
H	`HGate`	1	—	Hadamard
X	`XGate`	1	—	Pauli-X (NOT)
Y	`YGate`	1	—	Pauli-Y
Z	`ZGate`	1	—	Pauli-Z
I	`IGate`	1	—	Identity
S	`SGate`	1	—	\(\pi/2\) phase
Sdg	`SdgGate`	1	—	S-dagger
T	`TGate`	1	—	\(\pi/4\) phase
Tdg	`TdgGate`	1	—	T-dagger
SX	`SXGate`	1	—	\(\sqrt{X}\)
SXdg	`SXdgGate`	1	—	\(\sqrt{X}\)-dagger
RX	`RXGate`	1	\(\theta\)	X-rotation
RY	`RYGate`	1	\(\theta\)	Y-rotation
RZ	`RZGate`	1	\(\theta\)	Z-rotation
R	`RGate`	1	\(\theta, \phi\)	General rotation
Phase	`PhaseGate`	1	\(\lambda\)	Phase gate
U1	`U1Gate`	1	\(\lambda\)	U1 (\(= \text{Phase}\))
U2	`U2Gate`	1	\(\phi, \lambda\)	U2
U3	`U3Gate`	1	\(\theta, \phi, \lambda\)	General unitary
CX	`CXGate`	2	—	CNOT
CY	`CYGate`	2	—	Controlled-Y
CZ	`CZGate`	2	—	Controlled-Z
CH	`CHGate`	2	—	Controlled-H
CS	`CSGate`	2	—	Controlled-S
CSdg	`CSdgGate`	2	—	Controlled-Sdg
CSX	`CSXGate`	2	—	Controlled-SX
CRX	`CRXGate`	2	\(\theta\)	Controlled-RX
CRY	`CRYGate`	2	\(\theta\)	Controlled-RY
CRZ	`CRZGate`	2	\(\theta\)	Controlled-RZ
CP	`CPhaseGate`	2	\(\lambda\)	Controlled-Phase
CU1	`CU1Gate`	2	\(\lambda\)	Controlled-U1
CU3	`CU3Gate`	2	\(\theta, \phi, \lambda\)	Controlled-U3
SWAP	`SwapGate`	2	—	SWAP
iSWAP	`iSwapGate`	2	—	iSWAP
DCX	`DCXGate`	2	—	Double-CX
ECR	`ECRGate`	2	—	Echoed CR
RZZ	`RZZGate`	2	\(\theta\)	ZZ-interaction
RXX	`RXXGate`	2	\(\theta\)	XX-interaction
RYY	`RYYGate`	2	\(\theta\)	YY-interaction
RZX	`RZXGate`	2	\(\theta\)	ZX-interaction
CCX	`ToffoliGate`	3	—	Toffoli
CCZ	`CCZGate`	3	—	Controlled-CZ
CSWAP	`FredkinGate`	3	—	Fredkin

API Reference¶

Base Class¶

Gate `dataclass` ¶

Gate(
    name: str,
    qubits: tuple[int, ...],
    params: tuple[float, ...] = tuple(),
)

Base class for all quantum gates.

ATTRIBUTE	DESCRIPTION
`name`	Human-readable gate name (e.g., "H", "CNOT", "RZ"). TYPE: `str`
`qubits`	Tuple of qubit indices this gate acts on. TYPE: `tuple[int, ...]`
`params`	Tuple of float parameters (e.g., rotation angles). TYPE: `tuple[float, ...]`
`num_qubits`	Number of qubits this gate acts on. TYPE: `int`

Attributes¶

num_qubits `property` ¶

num_qubits: int

Number of qubits this gate acts on.

Functions¶

matrix ¶

matrix() -> ndarray

Return the unitary matrix representation of this gate.

RETURNS	DESCRIPTION
`ndarray`	A 2^n x 2^n complex numpy array representing the gate unitary.

RAISES	DESCRIPTION
`NotImplementedError`	If matrix is not defined for this gate.

Single-Qubit Gates¶

HGate ¶

HGate(qubit: int)

Bases: Gate

Hadamard gate.

XGate ¶

XGate(qubit: int)

Bases: Gate

Pauli-X (NOT) gate.

YGate ¶

YGate(qubit: int)

Bases: Gate

Pauli-Y gate.

ZGate ¶

ZGate(qubit: int)

Bases: Gate

Pauli-Z gate.

IGate ¶

IGate(qubit: int)

Bases: Gate

Identity gate.

SGate ¶

SGate(qubit: int)

Bases: Gate

S (√Z) gate — phase gate with π/2 rotation.

SdgGate ¶

SdgGate(qubit: int)

Bases: Gate

S-dagger (S†) gate -- adjoint of S.

TGate ¶

TGate(qubit: int)

Bases: Gate

T (√S) gate — phase gate with π/4 rotation.

TdgGate ¶

TdgGate(qubit: int)

Bases: Gate

T-dagger (T†) gate -- adjoint of T.

SXGate ¶

SXGate(qubit: int)

Bases: Gate

Square root of X gate.

SXdgGate ¶

SXdgGate(qubit: int)

Bases: Gate

Square root of X dagger gate.

RXGate ¶

RXGate(qubit: int, theta: float)

Bases: Gate

Rotation around X-axis by angle theta.

RYGate ¶

RYGate(qubit: int, theta: float)

Bases: Gate

Rotation around Y-axis by angle theta.

RZGate ¶

RZGate(qubit: int, theta: float)

Bases: Gate

Rotation around Z-axis by angle theta.

RGate ¶

RGate(qubit: int, theta: float, phi: float)

Bases: Gate

General rotation gate R(theta, phi) on the Bloch sphere.

PhaseGate ¶

PhaseGate(qubit: int, lam: float)

Bases: Gate

Phase gate P(lam) = diag(1, e^{i*lam}).

U1Gate ¶

U1Gate(qubit: int, lam: float)

Bases: Gate

U1 gate -- equivalent to Phase gate. U1(lam) = diag(1, e^{i*lam}).

U2Gate ¶

U2Gate(qubit: int, phi: float, lam: float)

Bases: Gate

U2 gate -- U2(phi, lam) = U3(pi/2, phi, lam).

U3Gate ¶

U3Gate(qubit: int, theta: float, phi: float, lam: float)

Bases: Gate

General single-qubit rotation U3(theta, phi, lambda).

Two-Qubit Gates¶

CXGate ¶

CXGate(control: int, target: int)

Bases: Gate

Controlled-X (CNOT) gate.

CYGate ¶

CYGate(control: int, target: int)

Bases: Gate

Controlled-Y gate.

CZGate ¶

CZGate(control: int, target: int)

Bases: Gate

Controlled-Z gate.

CHGate ¶

CHGate(control: int, target: int)

Bases: Gate

Controlled-Hadamard gate.

CSGate ¶

CSGate(control: int, target: int)

Bases: Gate

Controlled-S gate.

CSdgGate ¶

CSdgGate(control: int, target: int)

Bases: Gate

Controlled-S-dagger gate.

CSXGate ¶

CSXGate(control: int, target: int)

Bases: Gate

Controlled-SX gate.

CRXGate ¶

CRXGate(control: int, target: int, theta: float)

Bases: Gate

Controlled-RX gate.

CRYGate ¶

CRYGate(control: int, target: int, theta: float)

Bases: Gate

Controlled-RY gate.

CRZGate ¶

CRZGate(control: int, target: int, theta: float)

Bases: Gate

Controlled-RZ gate.

CPhaseGate ¶

CPhaseGate(control: int, target: int, lam: float)

Bases: Gate

Controlled-Phase gate. CP(lam) = diag(1, 1, 1, e^{i*lam}).

CU1Gate ¶

CU1Gate(control: int, target: int, lam: float)

Bases: Gate

Controlled-U1 gate -- equivalent to CPhase.

CU3Gate ¶

CU3Gate(
    control: int,
    target: int,
    theta: float,
    phi: float,
    lam: float,
)

Bases: Gate

Controlled-U3 gate.

SwapGate ¶

SwapGate(qubit1: int, qubit2: int)

Bases: Gate

SWAP gate — swaps two qubits.

iSwapGate ¶

iSwapGate(qubit1: int, qubit2: int)

Bases: Gate

iSWAP gate.

DCXGate ¶

DCXGate(qubit1: int, qubit2: int)

Bases: Gate

Double-CX gate -- CX(0,1) followed by CX(1,0).

ECRGate ¶

ECRGate(qubit1: int, qubit2: int)

Bases: Gate

Echoed Cross-Resonance gate.

RZZGate ¶

RZZGate(qubit1: int, qubit2: int, theta: float)

Bases: Gate

ZZ-rotation gate RZZ(theta) = exp(-i * theta/2 * Z⊗Z).

RXXGate ¶

RXXGate(qubit1: int, qubit2: int, theta: float)

Bases: Gate

XX-rotation gate RXX(theta) = exp(-i * theta/2 * X⊗X).

RYYGate ¶

RYYGate(qubit1: int, qubit2: int, theta: float)

Bases: Gate

YY-rotation gate RYY(theta) = exp(-i * theta/2 * Y⊗Y).

RZXGate ¶

RZXGate(qubit1: int, qubit2: int, theta: float)

Bases: Gate

ZX-rotation gate RZX(theta) = exp(-i * theta/2 * Z⊗X).

Three-Qubit Gates¶

ToffoliGate ¶

ToffoliGate(control1: int, control2: int, target: int)

Bases: Gate

Toffoli (CCX) gate — double-controlled NOT.

CCZGate ¶

CCZGate(control1: int, control2: int, target: int)

Bases: Gate

Double-controlled Z (CCZ) gate.

FredkinGate ¶

FredkinGate(control: int, target1: int, target2: int)

Bases: Gate

Fredkin (CSWAP) gate — controlled SWAP.

Special Operations¶

Measure ¶

Measure(qubit: int, classical_bit: int | None = None)

Bases: Gate

Measurement in the computational basis.

Barrier ¶

Barrier(qubits: Sequence[int])

Bases: Gate

Barrier — prevents gate optimization across this point.

Reset ¶

Reset(qubit: int)

Bases: Gate

Reset gate -- resets a qubit to the |0> state.

Gate Map¶

The GATE_MAP dictionary maps string names to gate classes for use in deserialization and interop:

from quantsdk.gates import GATE_MAP

# 55 entries mapping string names -> Gate classes
print(list(GATE_MAP.keys()))
# ['h', 'x', 'y', 'z', 'i', 'id', 's', 'sdg', 't', 'tdg', ...]

Gates¶

Gate Hierarchy¶

Quick Reference Table¶

API Reference¶

Base Class¶

Gate dataclass ¶

Attributes¶

num_qubits property ¶

Functions¶

matrix ¶

Single-Qubit Gates¶

HGate ¶

XGate ¶

YGate ¶

ZGate ¶

IGate ¶

SGate ¶

SdgGate ¶

TGate ¶

TdgGate ¶

SXGate ¶

SXdgGate ¶

RXGate ¶

RYGate ¶

RZGate ¶

RGate ¶

PhaseGate ¶

U1Gate ¶

U2Gate ¶

U3Gate ¶

Two-Qubit Gates¶

CXGate ¶

CYGate ¶

CZGate ¶

CHGate ¶

CSGate ¶

CSdgGate ¶

CSXGate ¶

CRXGate ¶

CRYGate ¶

CRZGate ¶

CPhaseGate ¶

CU1Gate ¶

CU3Gate ¶

SwapGate ¶

iSwapGate ¶

DCXGate ¶

ECRGate ¶

RZZGate ¶

RXXGate ¶

RYYGate ¶

RZXGate ¶

Three-Qubit Gates¶

ToffoliGate ¶

CCZGate ¶

FredkinGate ¶

Special Operations¶

Measure ¶

Barrier ¶

Reset ¶

Gate Map¶

Gate `dataclass` ¶

num_qubits `property` ¶