def QRM(omega0, omegac, ncav=2):
'''
Quantum Rabi model / Jaynes-Cummings model
Parameters
----------
omega0 : float
atomic transition frequency
omegac : float
cavity frequency
g : float
cavity-molecule coupling strength
Returns
-------
rabi: object
'''
s0, sx, sy, sz = pauli()
hmol = 0.5 * omega0 * (-sz + s0)
mol = Mol(hmol, sx) # atom
cav = Cavity(omegac, ncav) # cavity
return Polariton(mol, cav)
def test_sesolver():
s0, sx, sy, sz = pauli()
H = (-0.05) * sz - 0. * sx
solver = SESolver(H)
Nt = 1000
dt = 4
psi0 = (basis(2, 0) + basis(2, 1)) / np.sqrt(2)
start_time = time.time()
result = solver.evolve(psi0, dt=dt, Nt=Nt, e_ops=[sx])
print("--- %s seconds ---" % (time.time() - start_time))
start_time = time.time()
times = np.arange(Nt) * dt
r = _ode_solver(H, psi0, dt=dt, Nt=Nt, nout=2, e_ops=[sx])
print("--- %s seconds ---" % (time.time() - start_time))
# test correlation functions
# corr = solver.correlation_3p_1t(psi0=psi0, oplist=[s0, sx, sx],
# dt=0.05, Nt=Nt)
#
# times = np.arange(Nt)
#
import matplotlib.pyplot as plt
fig, ax = plt.subplots()
ax.plot(times, result.observables[:, 0])
ax.plot(r.times, r.observables[:, 0], '--')
# ax.plot(times, corr.real)
plt.show()
# store the reduced density matrix
f.write(
fmt.format(t, ado[0, 0, 0], ado[0, 1, 0], ado[1, 0, 0], ado[1, 1,
0]))
#sz += -1j * commutator(sz, H) * dt
f.close()
return ado[:, :, 0]
if __name__ == '__main__':
from lime.phys import pauli
s0, sx, sy, sz = pauli()
H = 2 * np.pi * 0.1 * sx
psi0 = basis(2, 0)
rho0 = ket2dm(psi0)
mesolver = Lindblad_solver(H, c_ops=[0.2 * sx], e_ops=[sz])
Nt = 200
dt = 0.05
L = mesolver.liouvillian()
#result = mesolver.evolve(rho0, dt, Nt=Nt, return_result=True)
#corr = mesolver.correlation_3op_2t(rho0, [sz, sz, sz], dt, Nt, Ntau=Nt)