Qdislib — 04 · Backends and interop

Qdislib is backend-agnostic: the same workflow drives Qibo, Qiskit and CUDA-Q — only the software= argument changes. Any framework that exports OpenQASM 2.0 can also feed in via from_qasm.

from qibo import models, gates


def example_circuit():
    """A small 5-qubit circuit: cuttable (CZ chain), non-trivial <ZZZZZ> ~= 0.44."""
    circuit = models.Circuit(5)
    circuit.add(gates.RY(0, 0.8))
    circuit.add(gates.CZ(0, 1))
    circuit.add(gates.RY(1, 0.5))
    circuit.add(gates.CZ(1, 2))
    circuit.add(gates.RY(2, 0.6))
    circuit.add(gates.CZ(2, 3))
    circuit.add(gates.RY(3, 0.4))
    circuit.add(gates.CZ(3, 4))
    circuit.add(gates.RX(4, 0.3))
    return circuit


circuit = example_circuit()
print(circuit.draw())

import Qdislib as qd

circuit = example_circuit()
cut = qd.find_cut(circuit, gate_cut=True, wire_cut=False)
print("cut:", cut)

Qibo

print("qibo  :", qd.gate_cutting(example_circuit(), cut, software="qibo", shots=8192))

Qiskit

Same circuit and cut, executed on Qiskit Aer (pip install Qdislib[qiskit]).

print("qiskit:", qd.gate_cutting(example_circuit(), cut, software="qiskit", shots=8192))

CUDA-Q

With pip install Qdislib[cudaq] you can build the circuit as a CUDA-Q kernel and run with software="cudaq" (GPU when available, CPU otherwise). find_cut works directly on a kernel too.

import cudaq
import Qdislib as qd

@cudaq.kernel
def kernel():
    q = cudaq.qvector(5)
    ry(0.8, q[0])
    z.ctrl(q[0], q[1])
    ry(0.5, q[1])
    z.ctrl(q[1], q[2])
    ry(0.6, q[2])
    z.ctrl(q[2], q[3])
    ry(0.4, q[3])
    z.ctrl(q[3], q[4])
    rx(0.3, q[4])

cut = qd.find_cut(kernel, gate_cut=True, wire_cut=False)
print(qd.gate_cutting(kernel, cut, software="cudaq", shots=8192))

Interop: from_qasm

Bring circuits from Cirq, PennyLane, Braket, … through their OpenQASM 2.0 export. Here we round-trip a Qibo circuit through QASM into a Qiskit one and cut that.

qasm = example_circuit().to_qasm()
qc = qd.from_qasm(qasm, software="qiskit")
cut = qd.find_cut(qc, gate_cut=True, wire_cut=False)
print("cut on the imported circuit:", cut)
print("value:", qd.gate_cutting(qd.from_qasm(qasm, software="qiskit"), cut, software="qiskit", shots=8192))

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Next: 05 · Observables — beyond <ZZZZZ>.