def get_opc(self):
'''
Construct <OpCollection> for a chain.
Return:
<OpCollection>, the operator collection.
'''
impurity=self.impurity
bath=self.bath
nsite=bath.nsite+1
spaceconfig1=impurity.spaceconfig
config=list(spaceconfig1.config)
config[-2]=nsite
spaceconfig=SuperSpaceConfig(config)
elist,tlist=self.elist_rescaled,self.tlist_rescaled
tlist2=swapaxes(tlist.conj(),-1,-2)
ebonds=[Bond(zeros(2),i,i) for i in xrange(len(elist))]
tbonds=[Bond([1.,0],i,i+1) for i in xrange(len(tlist))]
tbonds2=[Bond([-1.,0],i+1,i) for i in xrange(len(tlist))]
opc=op_on_bond('E',spaceconfig=spaceconfig,mats=elist,bonds=ebonds)
opc=opc+op_on_bond('T',spaceconfig=spaceconfig,mats=concatenate([tlist2,tlist],axis=0),bonds=tbonds2+tbonds)
opc.label='H'
opc+=impurity.get_interaction()
return op2collection(opc).compactify()
def __init__(self,t,mu,M,N,periodic=False,usekspace=False):
if usekspace and not periodic:
raise ValueError('Don\'t be silly, how can you use kspace with non-periodic system!')
self.t,self.mu,self.M=t,mu,M
self.N=N
self.periodic=periodic
if usekspace:
spaceconfig=SpaceConfig([1,2,2,1],kspace=True)
hgen=KHGenerator(spaceconfig=spaceconfig,propergauge=False)
else:
spaceconfig=SpaceConfig(chorder([1,2,2*self.N,1]),kspace=False)
hgen=RHGenerator(spaceconfig=spaceconfig)
#define the operator of the system
hgen.register_params({
'-t':-self.t,
'M':self.M,
'-mu':-self.mu,
})
#define a structure and initialize bonds.
rlattice=Chain(N=N,catoms=[array([0.]),array([0.8])],a=array([2.]))
if periodic:
rlattice.usegroup(TranslationGroup(rlattice.N[:,newaxis]*rlattice.a,per=ones(1,dtype='bool')))
hgen.uselattice(rlattice)
b1s=rlattice.cbonds[1] if usekspace else rlattice.getbonds(1) #the nearest neighbor
b2s=rlattice.cbonds[2] if usekspace else rlattice.getbonds(2) #the nearest neighbor
#add the hopping term.
op_t1=op_simple_hopping(label='hop1',spaceconfig=spaceconfig,bonds=b1s+b2s)
hgen.register_operator(op_t1,param='-t')
op_n=op_simple_onsite(label='n',spaceconfig=spaceconfig)
hgen.register_operator(op_n,param='-mu')
#add the interaction term
I2=identity(2)
op_M_even=op_on_bond(label='Sx',spaceconfig=spaceconfig,mats=[sx]*len(b1s),bonds=b1s)
op_M_odd=op_on_bond(label='-Sx',spaceconfig=spaceconfig,mats=[-sx]*len(b2s),bonds=b2s)
hgen.register_operator(op_M_even,param='M')
hgen.register_operator(op_M_odd,param='M')
self.hgen=hgen
def get_opc(self):
'''
Construct <OpCollection> for a chain.
Return:
<OpCollection>, the operator collection.
'''
impurity = self.impurity
bath = self.bath
# the new space configuration.
nsite = self.nsite
spaceconfig1 = impurity.spaceconfig
config = list(spaceconfig1.config)
config[-2] = nsite
spaceconfig = SuperSpaceConfig(config)
elist, tlist = self.bath.elist, self.bath.tlist
if impurity.H0 is not None:
elist = concatenate([self.impurity.H0[newaxis, ...], elist],
axis=0)
tlist = concatenate([self.bath.t0[newaxis, ...], tlist], axis=0)
tlist2 = swapaxes(tlist.conj(), -1, -2)
ebonds = [Bond(i, i, zeros(2)) for i in range(len(elist))]
tbonds = [Bond(i, i + 1, [1., 0]) for i in range(len(tlist))]
tbonds2 = [-b for b in tbonds]
opc = op_on_bond('E',
spaceconfig=spaceconfig,
mats=elist,
bonds=ebonds)
opc = opc + op_on_bond('T',
spaceconfig=spaceconfig,
mats=concatenate([tlist2, tlist], axis=0),
bonds=tbonds2 + tbonds)
opc.label = 'H'
opc += impurity.get_interaction()
opcl = op2collection(opc)
insert_Zs(opcl, spaceconfig1)
return opcl
def __init__(self,t,Delta,mu,nsite,periodic=False,manybody=True):
self.t,self.mu,self.Delta=t,mu,Delta
self.nsite=nsite
self.periodic=periodic
self.manybody=manybody
if manybody:
spaceconfig=SuperSpaceConfig(chorder([1,1,self.nsite,1]))
else:
spaceconfig=SpaceConfig(chorder([2,1,self.nsite,1]))
hgen=RHGenerator(spaceconfig=spaceconfig)
#define the operator of the system
hgen.register_params({
'-t':-self.t if not self.manybody else 2*self.t,
'Delta':self.Delta,
'-mu':-self.mu,
})
#define a structure and initialize bonds.
rlattice=Chain(N=nsite)
if periodic:
rlattice.usegroup(TranslationGroup(rlattice.N[:,newaxis]*rlattice.a,per=ones(1,dtype='bool')))
hgen.uselattice(rlattice)
b1s=rlattice.getbonds(1) #the nearest neighbor
#add the hopping term.
op_t1=op_simple_hopping(label='hop1',spaceconfig=spaceconfig,bonds=b1s)
hgen.register_operator(op_t1,param='-t')
op_n=op_simple_onsite(label='n',spaceconfig=spaceconfig)
hgen.register_operator(op_n,param='-mu')
#add the p-wave term
if not manybody:
op_d=op_on_bond(label='pp',spaceconfig=spaceconfig,mats=[(1j if b.bondv[0]>0 else -1j)*sy for b in b1s],bonds=b1s)
hgen.register_operator(op_d,param='Delta')
else:
op_d=sum([BBilinear(
index1=spaceconfig.c2ind(chorder([0,b.atom1,0])), #spin, atom orbit
index2=spaceconfig.c2ind(chorder([0,b.atom2,0])),
spaceconfig=spaceconfig,bondv=b.bondv,factor=1 if b.bondv[0]>0 else -1,indices_ndag=2) #spin, atom orbit
for b in b1s])
op_d=op_d+op_d.HC
hgen.register_operator(op_d,param='Delta')
self.hgen=hgen
self.qnumber='PM'
def __init__(self,t,mu,alpha,U,Delta,Vz,nsite,periodic=False,occ=False,kspace=True,resonance=False):
if kspace and not periodic:
raise ValueError('Don\'t be silly, how can you use kspace with non-periodic system!')
if kspace and occ:
raise ValueError('Don\'t be silly, how can you use kspace with occupation representation!')
if kspace and resonance:
raise ValueError('Don\'t be silly, how can you use kspace to study resonance!')
self.t,self.mu,self.alpha,self.U,self.Delta,self.Vz=t,mu,alpha,U,Delta,Vz
self.nsite=nsite
self.periodic=periodic
self.resonance=resonance
self.occ=occ
nambu=abs(self.Delta)>0 and not occ
#nambu=True
nnambu=2 if nambu else 1
junction_site=nsite/2
if occ:
spaceconfig=SuperSpaceConfig(chorder([1,2,self.nsite,1]))
hgen=RHGenerator(spaceconfig=spaceconfig)
elif kspace:
spaceconfig=SpaceConfig(chorder([nnambu,2,1,1]),kspace=True)
hgen=KHGenerator(spaceconfig=spaceconfig,propergauge=False)
else:
spaceconfig=SpaceConfig(chorder([nnambu,2,self.nsite,1]))
hgen=RHGenerator(spaceconfig=spaceconfig)
#define the operator of the system
hgen.register_params({
'-t/2':-self.t/2.,
'-alpha/2':-self.alpha/2.,
'U':self.U,
'Vz':self.Vz,
'-mu+t':-self.mu+self.t,
'Delta':self.Delta,
't':self.t,
})
#define a structure and initialize bonds.
rlattice=Chain(N=nsite)
if periodic:
rlattice.usegroup(TranslationGroup(rlattice.N[:,newaxis]*rlattice.a,per=ones(1,dtype='bool')))
hgen.uselattice(rlattice)
b1s=rlattice.cbonds[1] if kspace else rlattice.getbonds(1) #the nearest neighbor
b0s=rlattice.cbonds[0] if kspace else rlattice.getbonds(0) #the onsite bonds.
brs=[b for b in b0s if b.atom1>=junction_site]
bls=[b for b in b0s if b.atom1<junction_site]
#add the hopping term and chemical potential.
t0=time.time()
op_t1=op_simple_hopping(label='hop1',spaceconfig=spaceconfig,bonds=b1s)
hgen.register_operator(op_t1,param='-t/2')
t1=time.time()
if resonance:
op_n=op_on_bond(label='n',spaceconfig=spaceconfig,bonds=brs,mats=[kron(sz,identity(2))]*len(brs))
hgen.register_operator(op_n,param='t')
op_nl=op_on_bond(label='nl',spaceconfig=spaceconfig,bonds=bls,mats=[kron(sz,identity(2))]*len(bls))
hgen.register_operator(op_nl,param='-mu+t')
else:
op_n=op_simple_onsite(label='n',spaceconfig=spaceconfig)
hgen.register_operator(op_n,param='-mu+t')
t2=time.time()
#the rashba term
rmats=[1j*(sy if not nambu else kron(sz,sy))*(1 if b.bondv[0]>0 else -1) for b in b1s]
op_r=op_on_bond(label='rashba',spaceconfig=spaceconfig,bonds=b1s,mats=rmats)
hgen.register_operator(op_r,param='-alpha/2')
t3=time.time()
#the magnetic field
op_Vz=op_on_bond(label='Sz',spaceconfig=spaceconfig,bonds=b0s,mats=[sz if not nambu else kron(sz,sz)]*len(b0s))
hgen.register_operator(op_Vz,param='Vz')
t4=time.time()
if abs(Delta)>0:
#the cooper pairing term, if the resonace mode, only the left side is added.
if nambu:
if resonance:
op_D=op_on_bond(label='D',spaceconfig=spaceconfig,bonds=bls,mats=[-kron(sy,sy)]*len(bls))
else:
op_D=op_on_bond(label='D',spaceconfig=spaceconfig,bonds=b0s,mats=[-kron(sy,sy)]*len(b0s))
else:
op_D=op_supercooper(label='D',spaceconfig=spaceconfig,bonds=b0s,mats=[array([[0,1],[0,0]])]*len(b0s))
hgen.register_operator(op_D,param='Delta')
if occ:
#add the interaction term
op_ninj=op_U(label='ninj',spaceconfig=spaceconfig)
hgen.register_operator(op_ninj,param='U')
t5=time.time()
print 'Elapse -> t: %s, n: %s, r: %s, B: %s, D: %s'%(t1-t0,t2-t1,t3-t2,t4-t3,t5-t4)
self.hgen=hgen