def test_1x2(self):
"""Test a 1x2 lattice Bose-Hubbard model"""
self.logTestName()
self.eng.reset()
q = self.eng.register
H = bose_hubbard(1, 2, self.J, self.U)
with self.eng:
Fock(2) | q[0]
BoseHubbardPropagation(H, self.t, self.k) | q
state = self.eng.run('fock', cutoff_dim=7)
Hm = -self.J*np.sqrt(2)*np.array([[0, 1, 0], [1, 0, 1], [0, 1, 0]]) \
+ self.U*np.diag([1, 0, 1])
init_state = np.array([1, 0, 0])
exp = np.abs(np.dot(expm(-1j * self.t * Hm), init_state))**2
self.assertTrue(
np.allclose(state.fock_prob([2, 0]), exp[0], rtol=self.tol))
self.assertTrue(
np.allclose(state.fock_prob([1, 1]), exp[1], rtol=self.tol))
self.assertTrue(
np.allclose(state.fock_prob([0, 2]), exp[2], rtol=self.tol))
def test_global(self):
"""Test a 1x2 lattice Bose-Hubbard model in global mode"""
self.logTestName()
self.eng.reset()
q = self.eng.register
with self.eng:
Sgate(0.1) | q[2]
Fock(2) | q[0]
BoseHubbardPropagation(self.H, self.t, self.k, mode='global') | q
state = self.eng.run('fock', cutoff_dim=7, modes=[0, 1])
Hm = -self.J*np.sqrt(2)*np.array([[0, 1, 0], [1, 0, 1], [0, 1, 0]]) \
+ self.U*np.diag([1, 0, 1])
init_state = np.array([1, 0, 0])
exp = np.abs(np.dot(expm(-1j * self.t * Hm), init_state))**2
self.assertTrue(
np.allclose(state.fock_prob([2, 0]), exp[0], rtol=self.tol))
self.assertTrue(
np.allclose(state.fock_prob([1, 1]), exp[1], rtol=self.tol))
self.assertTrue(
np.allclose(state.fock_prob([0, 2]), exp[2], rtol=self.tol))
def test_non_hermitian(self):
"""Tests exception if non-Hermitian H"""
with self.assertRaises(ValueError):
H = QuadOperator('q0', 1 + 2j)
BoseHubbardPropagation(H, self.t, self.k, hbar=self.hbar)
def test_outside_context_no_hbar(self):
"""Tests exception if outside the engine with no hbar"""
with self.assertRaises(ValueError):
BoseHubbardPropagation(self.Hquad, self.t, self.k)
from openfermion.hamiltonians import bose_hubbard
import strawberryfields as sf
from strawberryfields.ops import *
from sfopenboson.ops import BoseHubbardPropagation
H = bose_hubbard(1, 2, 1, 1.5)
eng, q = sf.Engine(2)
with eng:
Fock(2) | q[1]
BoseHubbardPropagation(H, 1.086, 20) | q
state = eng.run('fock', cutoff_dim=3)
print("Prob(2,0) = ", state.fock_prob([2,0]))
print("Prob(1,1) = ", state.fock_prob([1,1]))
print("Prob(0,2) = ", state.fock_prob([0,2]))