def get_Ising(self, h, J=1.):
'''Get the hamiltonian.'''
#the hamiltonian for Ising model
Sz = opunit_Sz(spaceconfig=SpinSpaceConfig([1, 2]))
Sx = opunit_Sx(spaceconfig=SpinSpaceConfig([1, 2]))
H = -J * Sz.as_site(0) * Sz.as_site(1) + h * Sx.as_site(0)
return H
def __init__(self,J,Jz,h,nsite,J2=0,J2z=None):
self.spaceconfig=SpinSpaceConfig([2,1])
I=OpUnitI(hndim=2)
scfg=SpinSpaceConfig([2,1])
Sx=opunit_Sx(spaceconfig=scfg)
Sy=opunit_Sy(spaceconfig=scfg)
Sz=opunit_Sz(spaceconfig=scfg)
#with second nearest hopping terms.
if J2==0:
self.H_serial2=None
return
elif J2z==None:
J2z=J2
SL=[]
for i in xrange(nsite):
Sxi,Syi,Szi=copy.copy(Sx),copy.copy(Sy),copy.copy(Sz)
Sxi.siteindex=i
Syi.siteindex=i
Szi.siteindex=i
SL.append(array([Sxi,Syi,sqrt(J2z/J2)*Szi]))
ops=[]
for i in xrange(nsite-1):
ops.append(J*SL[i].dot(SL[i+1]))
if i<nsite-2 and J2z!=0:
ops.append(J2*SL[i].dot(SL[i+2]))
mpc=sum(ops)
self.H_serial=mpc
def __init__(self, J, Jz, h, nsite, J2=0, J2z=None):
self.spaceconfig = SpinSpaceConfig([1, 2])
I = OpUnitI(hndim=2)
scfg = SpinSpaceConfig([1, 2])
Sx = opunit_Sx(spaceconfig=scfg)
Sy = opunit_Sy(spaceconfig=scfg)
Sz = opunit_Sz(spaceconfig=scfg)
#with second nearest hopping terms.
if J2 == 0:
self.H_serial2 = None
return
elif J2z == None:
J2z = J2
SL = []
for i in xrange(nsite):
Sxi, Syi, Szi = copy.copy(Sx), copy.copy(Sy), copy.copy(Sz)
Sxi.siteindex = i
Syi.siteindex = i
Szi.siteindex = i
SL.append(array([Sxi, Syi, sqrt(J2z / J2) * Szi]))
ops = []
for i in xrange(nsite - 1):
ops.append(J * SL[i].dot(SL[i + 1]))
if i < nsite - 2 and J2z != 0:
ops.append(J2 * SL[i].dot(SL[i + 2]))
mpc = sum(ops)
self.H_serial = mpc
def __init__(self,J1,J2,K,Jp,nsite,impurity_site=None):
self.spaceconfig=SpinSpaceConfig([2,1])
if impurity_site is None:
impurity_site=nsite/2 #nsite/2 and nsite/2-1
self.impurity_site=impurity_site
self.J1,self.J2,self.K,self.Jp=J1,J2,K,Jp
I=OpUnitI(hndim=self.spaceconfig.hndim)
Sx=opunit_Sx(spaceconfig=self.spaceconfig)
Sy=opunit_Sy(spaceconfig=self.spaceconfig)
Sz=opunit_Sz(spaceconfig=self.spaceconfig)
SL=[]
for i in xrange(nsite):
Sxi,Syi,Szi=copy.deepcopy(Sx),copy.deepcopy(Sy),copy.deepcopy(Sz)
Sxi.siteindex=i
Syi.siteindex=i
Szi.siteindex=i
SL.append(array([Sxi,Syi,Szi]))
ops=[]
for i in xrange(nsite-1):
factor1=J1
if i==impurity_site or i==impurity_site-2:
factor1*=Jp
elif i==impurity_site-1:
factor1*=K
ops.append(factor1*SL[i].dot(SL[i+1]))
if i<nsite-2 and i!=impurity_site-1 and i!=impurity_site-2:
factor2=J2
if i==impurity_site-3 or i==impurity_site:
factor2*=Jp
ops.append(factor2*SL[i].dot(SL[i+2]))
mpc=sum(ops)
self.H_serial=mpc
def get_Haldane(self, D, J=1.):
'''Get the hamiltonian.'''
#the hamiltonian for Ising model
Sx = opunit_Sx(spaceconfig=SpinSpaceConfig([1, 3]))
Sy = opunit_Sy(spaceconfig=SpinSpaceConfig([1, 3]))
Sz = opunit_Sz(spaceconfig=SpinSpaceConfig([1, 3]))
H = J * (
Sz.as_site(0) * Sz.as_site(1) + Sx.as_site(0) * Sx.as_site(1) +
Sy.as_site(0) * Sy.as_site(1)) + D * Sz.as_site(0) * Sz.as_site(0)
return H
def test_loc_observe():
nsite = 10
(E, mps), info = get_spec(nsite, trunc_steps=[], return_vecs=True)
model = info['model']
sx = opunit_Sx(spaceconfig=model.spaceconfig)
sz = opunit_Sz(spaceconfig=model.spaceconfig)
sy = opunit_Sy(spaceconfig=model.spaceconfig)
# measure Sx(i)
ion()
for isite in range(nsite):
res = get_expect(sz.as_site(isite), mps)[0, 0].diagonal()
# res=fft.fft(res)
plot(res)
pdb.set_trace()
def __init__(self, g, h, nsite, J=1):
self.spaceconfig = SpinSpaceConfig([2, 1])
self.J, self.g, self.h, self.nsite = J, g, h, nsite
scfg = self.spaceconfig
I = OpUnitI(hndim=scfg.hndim)
Sx = opunit_Sx(spaceconfig=scfg) * 2
Sz = opunit_Sz(spaceconfig=scfg) * 2
opc = 0
for i in range(nsite):
hi = h - J if i == 0 or i == nsite - 1 else h
opc = opc + (hi * Sz.as_site(i) + g * Sx.as_site(i))
if i != nsite - 1:
opc = opc + J * Sz.as_site(i) * Sz.as_site(i + 1)
self.opc = opc
def __init__(self,J,h,nsite):
self.spaceconfig=SpinSpaceConfig([2,1])
self.J,self.h,self.nsite=J,h,nsite
I=OpUnitI(hndim=2)
Sz=opunit_Sz(spaceconfig=self.spaceconfig)
Sx=opunit_Sx(spaceconfig=self.spaceconfig)
wi=zeros((3,3),dtype='O')
wi[:,0],wi[2,1:]=(I,Sx,-h*Sz),(Sx,I)
WL=[copy.deepcopy(wi) for i in xrange(nsite)]
WL[0]=WL[0][2:]
WL[-1]=WL[-1][:,:1]
self.H=MPO(WL)
mpc=self.H.serialize()
mpc.compactify()
if isinstance(mpc,(OpString,OpUnit)):
mpc=OpCollection([mpc])
self.H_serial=mpc
self.qnumber='R'
def __init__(self,J,Jz,D,nsite,periodic=False):
self.spaceconfig=SpinSpaceConfig([3,1])
I=OpUnitI(hndim=self.spaceconfig.hndim)
Sx=opunit_Sx(spaceconfig=self.spaceconfig)
Sy=opunit_Sy(spaceconfig=self.spaceconfig)
Sz=opunit_Sz(spaceconfig=self.spaceconfig)
SL=[]
for i in xrange(nsite):
Sxi,Syi,Szi=copy.copy(Sx),copy.copy(Sy),copy.copy(Sz)
Sxi.siteindex=i
Syi.siteindex=i
Szi.siteindex=i
SL.append(array([Sxi,Syi,sqrt(Jz/J)*Szi]))
ops=[]
for i in xrange(nsite):
if periodic or i!=nsite-1:
ops.append(J*SL[i%nsite].dot(SL[(i+1)%nsite]))
ops.append(D*SL[i][2]*SL[i][2])
mpc=sum(ops)
mpc.compactify()
self.H_serial=mpc