Ket API

Ket Quantum Programming Platform.

Ket is a comprehensive library designed for quantum programming, providing essential functions and classes to build quantum algorithms and applications. It facilitates the manipulation and storage of quantum states, measurement operations, and the computation of expected values.

Explore the documentation of individual submodules for in-depth information and more practical code examples.

All the functionality from the submodules is conveniently accessible within the ket namespace. Except for the qulib module.

Examples

• Grover algorithm

from math import sqrt, pi
import ket

def grover(size: int, oracle) -> int:
    p = ket.Process(simulator="dense", num_qubits=size)

    s = ket.H(p.alloc(size))

    steps = int((pi / 4) * sqrt(2**size))

    for _ in range(steps):
        oracle(s)
        with ket.around(ket.H, s):
            ket.phase_oracle(0, s)

    return ket.measure(s).value

• Quantum teleportation protocol

import ket

def teleport(alice_msg, alice_aux, bob_aux):
    ket.ctrl(alice_msg, ket.X)(alice_aux)
    ket.H(alice_msg)

    m0 = ket.measure(alice_msg)
    m1 = ket.measure(alice_aux)

    if m1.value == 1:
        ket.X(bob_aux)
    if m0.value == 1:
        ket.Z(bob_aux)

    return bob_aux

def bell(qubits):
    return ket.ctrl(ket.H(qubits[0]), ket.X)(qubits[1])

def message(qubit):
    ket.H(alice)
    ket.Z(alice)

p = ket.Process()

alice = p.alloc()  # alice = |0⟩
message(alice)     # alice = |–⟩

bob = teleport(alice, *bell(p.alloc(2)))  # bob  <- alice

ket.H(bob)         # bob   = |1⟩
bob_m = ket.measure(bob)
print("Expected measure 1, result =", bob_m.value)

Submodules

amazon	AmazonBraket Interface for Ket
base	Base classes for quantum programming.
expv	Expected value calculation utilities.
gates	Quantum gate definitions.
ibm	Module providing functionality to interact with IBM Quantum and IBM Cloud devices.
npsim	Live Execution Simulator Based on NumPy
operations	Functions to manipulate quantum operations.
quantumstate	Quantum state snapshot.
quforge	QuForge Interface for Ket
qulib	Quantum library.
remote	Remote quantum execution module.

ket_version() → list[str]

Return the version of the Ket platform components.