def test_dm_two_mode(self, setup_eng, hbar, cutoff, tol):
"""Tests multimode dm preparation"""
eng, prog = setup_eng(2)
ket0 = np.random.uniform(
-1, 1, cutoff) + 1j * np.random.uniform(-1, 1, cutoff)
ket0 = ket0 / np.linalg.norm(ket0)
ket1 = np.random.uniform(
-1, 1, cutoff) + 1j * np.random.uniform(-1, 1, cutoff)
ket1 = ket1 / np.linalg.norm(ket1)
ket = np.outer(ket0, ket1)
rho = np.einsum("ij,kl->ikjl", ket, ket.conj())
with prog.context as q:
ops.DensityMatrix(rho) | q
state = eng.run(prog).state
assert np.allclose(state.dm(), rho, atol=tol, rtol=0)
eng.reset()
prog = sf.Program(2)
state1 = BaseFockState(rho, 2, False, cutoff)
with prog.context as q:
ops.DensityMatrix(state1) | q
state2 = eng.run(prog).state
assert np.allclose(state1.dm(), state2.dm(), atol=tol, rtol=0)
def setup_two_mode_circuit(self, setup_eng, cutoff):
"""Create the circuit for following tests"""
eng_ref, q = setup_eng(2)
S = ops.Sgate(2)
B = ops.BSgate(2.234, -1.165)
initial_state = np.complex64(
np.random.rand(*[cutoff] * 4) + 1j * np.random.rand(*[cutoff] * 4))
with eng_ref:
ops.DensityMatrix(initial_state) | q
S | q[0]
B | q
S | q[1]
B | q
eng, q = sf.Engine(2)
with eng:
S | q[0]
B | q
S | q[1]
B | q
rho = eng_ref.run().dm()
return eng, rho, initial_state
def test_dm_one_mode(self, setup_eng, hbar, cutoff, tol):
"""Tests single mode DM preparation"""
eng, prog = setup_eng(2)
ket = np.random.uniform(-1, 1, cutoff) + 1j * np.random.uniform(-1, 1, cutoff)
ket = ket / np.linalg.norm(ket)
rho = np.outer(ket, ket.conj())
with prog.context as q:
ops.DensityMatrix(rho) | q[0]
state = eng.run(prog, modes=[0])
assert np.allclose(state.dm(), rho, atol=tol, rtol=0)
eng.reset()
prog = sf.Program(2)
state1 = BaseFockState(rho, 1, False, cutoff, hbar)
with prog.context as q:
ops.DensityMatrix(state1) | q[0]
state2 = eng.run(prog, modes=[0])
assert np.allclose(state1.dm(), state2.dm(), atol=tol, rtol=0)
def test_dm_input_validation(self, setup_eng, hbar, cutoff, tol):
"""Test exceptions"""
mu = np.array([0.0, 0.0])
cov = np.identity(2)
state = GaussianState((mu, cov), 1, True, hbar)
eng, prog = setup_eng(2)
with prog.context as q:
with pytest.raises(ValueError, match="Gaussian states are not supported"):
ops.DensityMatrix(state) | q[0]
def test_dm_gaussian_state_object(self, setup_eng):
"""Test exception if loading a ket from a Gaussian state object"""
eng = sf.Engine('gaussian')
prog = sf.Program(1)
state = eng.run(prog)
# create new engine
eng, prog = setup_eng(1)
with prog.context as q:
with pytest.raises(ValueError, match="Gaussian states are not supported"):
ops.DensityMatrix(state) | q[0]
def test_dm_state_object(self, setup_eng, tol):
"""Test loading a density matrix from a prior state object"""
eng, prog = setup_eng(1)
with prog.context as q:
ops.Dgate(0.2) | q[0]
state1 = eng.run(prog).state
# create new engine
eng, prog = setup_eng(1)
with prog.context as q:
ops.DensityMatrix(state1) | q[0]
state2 = eng.run(prog).state
# verify it is the same state
assert np.allclose(state1.dm(), state2.dm(), atol=tol, rtol=0)
def setup_one_mode_circuit(self, setup_eng, cutoff):
"""Create the circuit for following tests"""
eng_ref, p0 = setup_eng(1)
S = ops.Sgate(1.1, -1.4)
L = ops.LossChannel(0.45)
initial_state = np.random.rand(cutoff, cutoff)
with p0.context as q:
ops.DensityMatrix(initial_state) | q
prog = sf.Program(p0)
with prog.context as q:
S | q
L | q
rho = eng_ref.run([p0, prog]).state.dm()
return prog, rho, initial_state
def setup_two_mode_circuit(self, setup_eng, cutoff):
"""Create the circuit for following tests"""
eng_ref, p0 = setup_eng(2)
S = ops.Sgate(2)
B = ops.BSgate(2.234, -1.165)
initial_state = np.complex64(
np.random.rand(*[cutoff] * 4) + 1j * np.random.rand(*[cutoff] * 4))
with p0.context as q:
ops.DensityMatrix(initial_state) | q
prog = sf.Program(p0)
with prog.context as q:
S | q[0]
B | q
S | q[1]
B | q
rho = eng_ref.run([p0, prog]).state.dm()
return prog, rho, initial_state
def setup_one_mode_circuit(self, setup_eng, cutoff):
"""Create the circuit for following tests"""
eng_ref, q = setup_eng(1)
S = ops.Sgate(1.1, -1.4)
L = ops.LossChannel(0.45)
initial_state = np.random.rand(cutoff, cutoff)
with eng_ref:
ops.DensityMatrix(initial_state) | q
S | q
L | q
eng, q = sf.Engine(1)
with eng:
S | q
L | q
rho = eng_ref.run().dm()
return eng, rho, initial_state
