def evolve_single_step(self, evolve_dt):
latest_bra_mps, latest_ket_mps = self.latest_mps
if len(self.evolve_times) % 2 == 1:
latest_ket_mps = latest_ket_mps.evolve(self.h_mpo, evolve_dt)
else:
latest_bra_mps = latest_bra_mps.evolve(self.h_mpo, -evolve_dt)
return BraKetPair(latest_bra_mps, latest_ket_mps)
def init_mps(self):
mmax = self.optimize_config.procedure[0][0]
i_mps = Mps.random(self.h_mpo.model, self.nexciton, mmax, 1)
i_mps.optimize_config = self.optimize_config
energy, i_mps = gs.optimize_mps(i_mps, self.h_mpo)
if self.spectratype == "emi":
operator = "a"
else:
operator = r"a^\dagger"
dipole_mpo = Mpo.onsite(self.model, operator, dipole=True)
if self.temperature != 0:
beta = self.temperature.to_beta()
# print "beta=", beta
# thermal_mpo = Mpo.exact_propagator(self.model, -beta / 2.0, space=self.space1, shift=self.shift1)
# ket_mps = thermal_mpo.apply(i_mps)
# ket_mps.normalize()
# no test, don't know work or not
i_mpdm = MpDm.from_mps(i_mps)
tp = ThermalProp(i_mpdm, self.h_mpo, exact=True, space=self.space1)
tp.evolve(None, 1, beta / 2j)
ket_mps = tp.latest_mps
else:
ket_mps = i_mps
a_ket_mps = dipole_mpo.apply(ket_mps, canonicalise=True)
a_ket_mps.canonical_normalize()
if self.temperature != 0:
a_bra_mps = ket_mps.copy()
else:
a_bra_mps = a_ket_mps.copy()
return BraKetPair(a_bra_mps, a_ket_mps)
def evolve_single_step(self, evolve_dt):
latest_bra_mps, latest_ket_mps = self.latest_mps
latest_ket_mps = latest_ket_mps.evolve_exact(self.h_mpo, evolve_dt,
self.space2)
if self.temperature != 0:
latest_bra_mps = latest_bra_mps.evolve_exact(
self.h_mpo, evolve_dt, self.space1)
return BraKetPair(latest_bra_mps, latest_ket_mps)
def init_mps(self):
if self.spectratype == "emi":
operator = "a"
else:
operator = r"a^\dagger"
dipole_mpo = Mpo.onsite(self.model, operator, dipole=True)
a_ket_mps = dipole_mpo.apply(self.get_imps(), canonicalise=True)
a_ket_mps.canonical_normalize()
a_ket_mps.evolve_config = self.evolve_config
a_bra_mps = a_ket_mps.copy()
return BraKetPair(a_bra_mps, a_ket_mps)
def evolve_single_step(self, evolve_dt):
latest_bra_mps, latest_ket_mps = self.latest_mps
latest_ket_mps = latest_ket_mps.evolve(self.h_mpo, evolve_dt)
return BraKetPair(latest_bra_mps, latest_ket_mps)