示例#1
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    def test_SCF_exact(self):
        
        nexciton= 1
        D_value = np.array([0.0, 0.0])
        mol = construct_mol(nlevels, D_value=D_value)
        TDH.construct_Ham_vib(mol)
        # DMRG calculation
        procedure = [[40,0.4],[40,0.2],[40,0.1],[40,0],[40,0]]
        
        MPS, MPSdim, MPSQN, MPO, MPOdim, MPOQN, MPOQNidx, MPOQNtot, ephtable, pbond = \
            MPSsolver.construct_MPS_MPO_2(mol, J, procedure[0][0], nexciton)
        energy = MPSsolver.optimization(MPS, MPSdim, MPSQN, MPO, MPOdim, 
                ephtable, pbond, nexciton, procedure, method="2site")
        dmrg_e = mpslib.dot(MPS, mpslib.mapply(MPO, MPS))
        
        # print occupation
        dmrg_occ = []
        for i in [0,1,2]:
            MPO, MPOdim = MPSsolver.construct_onsiteMPO(mol,pbond,"a^\dagger a",dipole=False,sitelist=[i])
            dmrg_occ.append(mpslib.dot(MPS, mpslib.mapply(MPO, MPS)))
        print "dmrg_occ", dmrg_occ

        WFN, Etot = TDH.SCF(mol, J, nexciton)
        self.assertAlmostEqual(Etot, dmrg_e)
        
        fe, fv = 1, 6
        HAM, Etot, A_el = TDH.construct_H_Ham(mol, J, nexciton, WFN, fe, fv, debug=True)
        self.assertAlmostEqual(Etot, dmrg_e)
        self.assertTrue(np.allclose(A_el.flatten(), dmrg_occ))
示例#2
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    def test_construct_MPO(self):
        Mmax = 10
        MPS1, MPSdim1, MPSQN1, MPO1, MPOdim1, MPOQN1, MPOQNidx1, MPOQNtot1, ephtable1, pbond1 = \
            MPSsolver.construct_MPS_MPO_2(mol, J, Mmax, nexciton, MPOscheme=1)
        MPS2, MPSdim2, MPSQN2, MPO2, MPOdim2, MPOQN2, MPOQNidx2, MPOQNtot2, ephtable2, pbond2 = \
            MPSsolver.construct_MPS_MPO_2(mol, J, Mmax, nexciton, MPOscheme=2)

        self.assertEqual(ephtable1, ephtable2)
        self.assertEqual(pbond1, pbond2)
        self.assertAlmostEqual( \
            mpslib.dot(MPO1, mpslib.conj(MPO1)) + \
            mpslib.dot(MPO2, mpslib.conj(MPO2)) - \
            mpslib.dot(MPO1, mpslib.conj(MPO2)) - \
            mpslib.dot(MPO2, mpslib.conj(MPO1)), 0.0)
示例#3
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 def test_construct_MPO_scheme3(self):
     Mmax = 10
     J = np.array([[0.0, -0.1, 0.0], [-0.1, 0.0, -0.3], [0.0, -0.3, 0.0]
                   ]) / constant.au2ev
     MPS2, MPSdim2, MPSQN2, MPO2, MPOdim2, MPOQN2, MPOQNidx2, MPOQNtot2, ephtable2, pbond2 = \
         MPSsolver.construct_MPS_MPO_2(mol, J, Mmax, nexciton, MPOscheme=2)
     MPS3, MPSdim3, MPSQN3, MPO3, MPOdim3, MPOQN3, MPOQNidx3, MPOQNtot3, ephtable3, pbond3 = \
         MPSsolver.construct_MPS_MPO_2(mol, J, Mmax, nexciton, MPOscheme=3)
     self.assertEqual(ephtable3, ephtable2)
     self.assertEqual(pbond3, pbond2)
     self.assertAlmostEqual( \
         mpslib.dot(MPO3, mpslib.conj(MPO3)) + \
         mpslib.dot(MPO2, mpslib.conj(MPO2)) - \
         mpslib.dot(MPO3, mpslib.conj(MPO2)) - \
         mpslib.dot(MPO2, mpslib.conj(MPO3)), 0.0)
示例#4
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def hybrid_DMRG_H_SCF(mol,
                      J,
                      nexciton,
                      dmrg_procedure,
                      niterations,
                      DMRGthresh=1e-5,
                      Hthresh=1e-5):
    '''
    The ground state SCF procedure of hybrid DMRG and Hartree(-Fock) approach
    '''
    nmols = len(mol)
    # initial guess
    # DMRG part
    MPS, MPSdim, MPSQN, MPO, MPOdim, MPOQN, MPOQNidx, MPOQNtot, ephtable, pbond = \
        MPSsolver.construct_MPS_MPO_2(mol, J, dmrg_procedure[0][0], nexciton)

    energy = MPSsolver.optimization(MPS, MPSdim, MPSQN, MPO, MPOdim,\
        ephtable, pbond, nexciton, dmrg_procedure)

    # Hartre part
    WFN = []
    for imol in xrange(nmols):
        for iph in xrange(mol[imol].nphs_hybrid):
            vw, vv = scipy.linalg.eigh(a=mol[imol].ph_hybrid[iph].H_vib_indep)
            WFN.append(vv[:, 0])

    # loop to optimize both parts
    for itera in xrange(niterations):
        print "Loop:", itera
        MPO, MPOdim, MPOQN, MPOQNidx, MPOQNtot, HAM, Etot = construct_hybrid_Ham(
            mol, J, MPS, WFN)
        print "Etot=", Etot

        MPS_old = mpslib.add(MPS, None)
        energy = MPSsolver.optimization(MPS, MPSdim, MPSQN, MPO, MPOdim,
                                        ephtable, pbond, nexciton,
                                        dmrg_procedure)

        WFN_old = WFN
        WFN = []
        for iham, ham in enumerate(HAM):
            w, v = scipy.linalg.eigh(a=ham)
            WFN.append(v[:, 0])

        # check convergence
        angle = np.absolute(mpslib.dot(mpslib.conj(MPS_old), MPS))

        res = [scipy.linalg.norm(np.tensordot(WFN[iwfn],WFN[iwfn],axes=0) \
         -np.tensordot(WFN_old[iwfn], WFN_old[iwfn], axes=0)) for iwfn in xrange(len(WFN))]

        if np.all(np.array(res) < Hthresh) and abs(angle - 1.) < DMRGthresh:
            print "SCF converge!"
            break

    # append the coefficient a
    WFN.append(1.0)

    return MPS, MPSQN, WFN, Etot
示例#5
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def Exact_Spectra_hybrid_TDDMRG_TDH(spectratype, mol, J, MPS, dipoleMPO, WFN, \
        nsteps, dt, E_offset=0.):
    '''
    exact spectra by hybrid TDDMRG/TDH approach for ZT abs and emi
    '''
    assert spectratype in ["emi", "abs"]

    if spectratype == "emi":
        space = "GS"
    else:
        space = "EX"

    AketMPS = mpslib.mapply(dipoleMPO, MPS)
    factor = mpslib.norm(AketMPS)
    AketMPS = mpslib.scale(AketMPS, 1. / factor)
    AbraMPS = mpslib.add(AketMPS, None)

    WFN[-1] *= factor
    WFNbra = copy.deepcopy(WFN)

    MPOprop, HAM, Etot = ExactPropagator_hybrid_TDDMRG_TDH(mol,
                                                           J,
                                                           AketMPS,
                                                           WFN,
                                                           -1.0j * dt,
                                                           space=space)
    print "TD Etot", Etot

    autocorr = []
    t = 0.
    for istep in xrange(nsteps):
        if istep != 0:
            t += dt
            WFN[-1] *= np.exp(-1.0j * Etot * dt)
            AketMPS = mpslib.mapply(MPOprop, AketMPS)
            TDH.unitary_propagation(HAM, WFN, dt)

        ft = mpslib.dot(mpslib.conj(AbraMPS), AketMPS)
        ft *= np.conj(WFNbra[-1]) * WFN[-1] * np.exp(-1.0j * E_offset * t)
        for iwfn in xrange(len(WFN) - 1):
            ft *= np.vdot(WFNbra[iwfn], WFN[iwfn])
        autocorr.append(ft)
        autocorr_store(autocorr, istep)

    return autocorr
示例#6
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    def test_optimization(self, value):
        MPS, MPSdim, MPSQN, MPO, MPOdim, MPOQN, MPOQNidx, MPOQNtot, ephtable, pbond = \
            MPSsolver.construct_MPS_MPO_2(mol, J, procedure[0][0], nexciton,
                    MPOscheme=value[0])
        energy = MPSsolver.optimization(MPS,
                                        MPSdim,
                                        MPSQN,
                                        MPO,
                                        MPOdim,
                                        ephtable,
                                        pbond,
                                        nexciton,
                                        procedure,
                                        method="2site")
        self.assertAlmostEqual(np.min(energy) * constant.au2ev, 2.28614053133)

        energy = MPSsolver.optimization(MPS,
                                        MPSdim,
                                        MPSQN,
                                        MPO,
                                        MPOdim,
                                        ephtable,
                                        pbond,
                                        nexciton,
                                        procedure,
                                        method="1site")
        self.assertAlmostEqual(np.min(energy) * constant.au2ev, 2.28614053133)

        MPSnew = MPSsolver.clean_MPS("L", MPS, ephtable, nexciton)
        self.assertAlmostEqual( \
            mpslib.dot(MPS, mpslib.conj(MPS)) + \
            mpslib.dot(MPSnew, mpslib.conj(MPSnew)) - \
            mpslib.dot(MPS, mpslib.conj(MPSnew)) - \
            mpslib.dot(MPSnew, mpslib.conj(MPS)), 0.0)

        MPSnew = MPSsolver.clean_MPS("R", MPS, ephtable, nexciton)
        self.assertAlmostEqual( \
            mpslib.dot(MPS, mpslib.conj(MPS)) + \
            mpslib.dot(MPSnew, mpslib.conj(MPSnew)) - \
            mpslib.dot(MPS, mpslib.conj(MPSnew)) - \
            mpslib.dot(MPSnew, mpslib.conj(MPS)), 0.0)
示例#7
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def ZeroTcorr_hybrid_TDDMRG_TDH(mol, J, iMPS, dipoleMPO, WFN0, nsteps, dt, ephtable,\
        thresh=0., TDDMRG_prop_method="C_RK4", E_offset=0., cleanexciton=None, QNargs=None):
    '''
    ZT linear spectra
    '''

    AketMPS = mpslib.mapply(dipoleMPO, iMPS, QNargs=QNargs)
    factor = mpslib.norm(AketMPS, QNargs=QNargs)
    AketMPS = mpslib.scale(AketMPS, 1. / factor, QNargs=QNargs)
    AbraMPS = mpslib.add(AketMPS, None, QNargs=QNargs)

    WFN0[-1] *= factor
    WFNket = copy.deepcopy(WFN0)
    WFNbra = copy.deepcopy(WFN0)

    autocorr = []
    t = 0.0
    for istep in xrange(nsteps):
        if istep != 0:
            t += dt
            if istep % 2 == 1:
                AketMPS, WFNket = hybrid_TDDMRG_TDH(mol, J, AketMPS, WFNket,\
                        dt, ephtable, thresh=thresh, cleanexciton=cleanexciton, QNargs=QNargs, \
                        TDDMRG_prop_method=TDDMRG_prop_method, TDH_prop_method="unitary")
            else:
                AbraMPS, WFNbra = hybrid_TDDMRG_TDH(mol, J, AbraMPS, WFNbra,\
                        -dt, ephtable, thresh=thresh, cleanexciton=cleanexciton, QNargs=QNargs, \
                        TDDMRG_prop_method=TDDMRG_prop_method, TDH_prop_method="unitary")

        ft = mpslib.dot(mpslib.conj(AbraMPS, QNargs=QNargs),
                        AketMPS,
                        QNargs=QNargs)
        ft *= np.conj(WFNbra[-1]) * WFNket[-1] * np.exp(-1.0j * E_offset * t)
        for iwfn in xrange(len(WFN0) - 1):
            ft *= np.vdot(WFNbra[iwfn], WFNket[iwfn])

        autocorr.append(ft)
        autocorr_store(autocorr, istep)

    return autocorr
示例#8
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def FiniteT_spectra_TDDMRG_TDH(spectratype, T, mol, J, nsteps, dt, insteps, pbond, ephtable,\
        thresh=0., ithresh=1e-4, TDDMRG_prop_method="C_RK4", E_offset=0., QNargs=None):
    '''
    FT linear spectra
    '''

    assert spectratype in ["abs", "emi"]

    dipoleMPO, dipoleMPOdim = MPSsolver.construct_onsiteMPO(mol,
                                                            pbond,
                                                            "a^\dagger",
                                                            dipole=True,
                                                            QNargs=QNargs)

    # construct initial thermal equilibrium density matrix and apply dipole matrix
    if spectratype == "abs":
        nexciton = 0
        DMMPO, DMH = FT_DM_hybrid_TDDMRG_TDH(mol, J, nexciton, T, insteps, pbond, ephtable, \
        thresh=ithresh, TDDMRG_prop_method=TDDMRG_prop_method, QNargs=QNargs, space="GS")
        DMMPOket = mpslib.mapply(dipoleMPO, DMMPO, QNargs=QNargs)
    else:
        nexciton = 1
        DMMPO, DMH = FT_DM_hybrid_TDDMRG_TDH(mol, J, nexciton, T, insteps, pbond, ephtable, \
        thresh=ithresh, TDDMRG_prop_method=TDDMRG_prop_method, QNargs=QNargs, space=None)
        if QNargs is not None:
            dipoleMPO[1] = [[0] * len(impsdim) for impsdim in dipoleMPO[1]]
            dipoleMPO[3] = 0
        DMMPOket = mpslib.mapply(DMMPO, dipoleMPO, QNargs=QNargs)

    factor = mpslib.norm(DMMPOket, QNargs=QNargs)
    DMMPOket = mpslib.scale(DMMPOket, 1. / factor, QNargs=QNargs)
    DMMPObra = mpslib.add(DMMPOket, None, QNargs=QNargs)

    DMH[-1] *= factor
    DMHket = copy.deepcopy(DMH)
    DMHbra = copy.deepcopy(DMH)

    autocorr = []
    t = 0.0

    def prop(DMMPO, DMH, dt):
        MPOprop, HAM, Etot = ExactPropagator_hybrid_TDDMRG_TDH(mol, J, \
                DMMPO,  DMH, -1.0j*dt, space="GS", QNargs=QNargs)
        DMMPO = mpslib.mapply(DMMPO, MPOprop, QNargs=QNargs)

        DMH[-1] *= np.exp(-1.0j * Etot * dt)
        for iham, hamprop in enumerate(HAM):
            w, v = scipy.linalg.eigh(hamprop)
            DMH[iham] = DMH[iham].dot(v).dot(np.diag(np.exp(-1.0j * dt *
                                                            w))).dot(v.T)

        DMMPO, DMH = hybrid_TDDMRG_TDH(mol, J, DMMPO, DMH, \
                -dt, ephtable, thresh=thresh, QNargs=QNargs, TDDMRG_prop_method=TDDMRG_prop_method, normalize=1.0)

        return DMMPO, DMH

    print("Real time dynamics starts!")

    for istep in xrange(nsteps):
        print("istep=", istep)
        if istep != 0:
            t += dt
            if istep % 2 == 0:
                DMMPObra, DMHbra = prop(DMMPObra, DMHbra, dt)
            else:
                DMMPOket, DMHket = prop(DMMPOket, DMHket, -dt)

        ft = mpslib.dot(mpslib.conj(DMMPObra, QNargs=QNargs),
                        DMMPOket,
                        QNargs=QNargs)
        ft *= np.conj(DMHbra[-1]) * DMHket[-1]
        for idm in xrange(len(DMH) - 1):
            ft *= np.vdot(DMHbra[idm], DMHket[idm])

        if spectratype == "emi":
            ft = np.conj(ft)

        # for emi bra and ket is conjugated
        ft *= np.exp(-1.0j * E_offset * t)

        autocorr.append(ft)
        autocorr_store(autocorr, istep)

    return autocorr