def show_ldos():
h = pickup_hamiltonian() # get the Hamiltonian
ew = abs(qtwrap.get("ldos_ewindow"))
energies = np.linspace(-ew, ew, 100)
delta = qtwrap.get("ldos_delta")
nk = int(qtwrap.get("ldos_nk"))
name = qtwrap.getbox("ldos_operator")
ldos.spatial_energy_profile(h,
operator=h.get_operator(name),
nk=nk,
delta=delta,
energies=energies)
execute_script(
'qh-map2d --input DOSMAP.OUT --xlabel Energy --ylabel "y-position" --zlabel DOS --title "Local DOS"'
)
def initialize():
""" Initialize the calculation"""
g = get_geometry() # get the geometry
ti = get("interlayer")
h = g.get_hamiltonian(has_spin=True, fun=specialhopping.multilayer(ti=ti))
h.add_zeeman([get("Bx"), get("By"), get("Bz")]) # Zeeman fields
h.add_sublattice_imbalance(get("mAB")) # sublattice imbalance
if abs(get("rashba")) > 0.0: h.add_rashba(get("rashba")) # Rashba field
h.add_antiferromagnetism(get("mAF")) # AF order
h.add_crystal_field(qtwrap.get("crystalfield"))
h.shift_fermi(get("fermi")) # shift fermi energy
h.shift_fermi(lambda r: get("bias") * r[2]) # interlayer bias
if abs(get("kanemele")) > 0.0:
h.add_kane_mele(get("kanemele")) # intrinsic SOC
if abs(get("haldane")) > 0.0:
h.add_haldane(get("haldane")) # intrinsic SOC
if abs(get("antihaldane")) > 0.0: h.add_antihaldane(get("antihaldane"))
if abs(get("antikanemele")) > 0.0:
h.add_anti_kane_mele(get("antikanemele"))
if abs(get("inplaneb")) > 0.0:
h.add_inplane_bfield(b=get("inplaneb"), phi=get("inplaneb_phi"))
if abs(get("swave")) > 0.0: h.add_swave(get("swave"))
# h.add_peierls(get("peierls")) # shift fermi energy
return h
def get_geometry(modify=True):
""" Create a 2d honeycomb lattice"""
n = int(qtwrap.get("cell_size")) # size of the unit cell
name = qtwrap.getbox("multilayer_type")
if name == "Twisted bilayer":
g = specialgeometry.twisted_bilayer(n)
elif name == "Aligned bilayer AA":
g = specialgeometry.twisted_multilayer(n, rot=[0, 0])
elif name == "Aligned bilayer AB":
gb = specialgeometry.multilayer_graphene(l=[0, 1])
g = specialgeometry.twisted_multilayer(n, rot=[0], g=gb, dz=6.0)
elif name == "Aligned trilayer ABC":
gb = specialgeometry.multilayer_graphene(l=[0, 1, 2])
g = specialgeometry.twisted_multilayer(n, rot=[0], g=gb, dz=6.0)
elif name == "Twisted trilayer 010":
g = specialgeometry.twisted_multilayer(n, rot=[0, 1, 0])
elif name == "Twisted trilayer 001":
g = specialgeometry.twisted_multilayer(n, rot=[0, 0, 1])
elif name == "Twisted bi-bilayer AB AB":
ps = [["AB", "AB"], [0, 1]]
g = specialgeometry.parse_twisted_multimultilayer(ps, n=n)
elif name == "Twisted bi-bilayer AB BA":
ps = [["AB", "BA"], [0, 1]]
g = specialgeometry.parse_twisted_multimultilayer(ps, n=n)
elif name == "Twisted bi-trilayer ABC":
ps = [["ABC", "ABC"], [0, 1]]
g = specialgeometry.parse_twisted_multimultilayer(ps, n=n)
else:
raise
# g = geometry.honeycomb_lattice()
# g = g.supercell(n)
if modify: g = modify_geometry(g) # remove atoms if necessary
return g
def show_time_evolution():
h = pickup_hamiltonian() # get hamiltonian
try: i = open("SELECTED_SINGLE_ATOM.INFO").read()
except: i = 0
if i=="": i=0
else: i = int(i)
if h.has_spin:
i = i*2
if qtwrap.getbox("channel_time_evolution")=="Down": i += 1
# print(i) ; return
if h.has_eh: i = i*4
tmax = qtwrap.get("tmax_time_evolution") # maximum time
timeevolution.evolve_local_state(h,i=i,ts=np.linspace(0.,tmax,100),
mode="green")
execute_script("qh-multitimeevolution") # plot the result
def initialize():
""" Initialize the calculation"""
g = get_geometry() # get the geometry
h = g.get_hamiltonian(has_spin=True)
h.add_zeeman([get("Bx"),get("By"),get("Bz")]) # Zeeman fields
h.add_sublattice_imbalance(get("mAB")) # sublattice imbalance
h.add_rashba(get("rashba")) # Rashba field
h.add_antiferromagnetism(get("mAF")) # AF order
h.add_crystal_field(qtwrap.get("crystalfield")) # add magnetic field
h.shift_fermi(get("fermi")) # shift fermi energy
h.add_kane_mele(get("kanemele")) # intrinsic SOC
h.add_haldane(get("haldane")) # intrinsic SOC
h.add_antihaldane(get("antihaldane"))
h.add_peierls(get("peierls")) # magnetic field
h.add_swave(get("swave"))
return h
def initialize():
""" Initialize the calculation"""
g = get_geometry() # get the geometry
twisted_matrix = specialhopping.twisted_matrix
has_spin = False
h = g.get_hamiltonian(is_sparse=True,
has_spin=has_spin,
is_multicell=True,
mgenerator=twisted_matrix(ti=get("tinter"),
lambi=7.0))
# workaround to put Fermi energy in zero approx
h.shift_fermi(-get("tinter") / 16.)
h.add_crystal_field(qtwrap.get("crystalfield"))
if abs(get("inplaneb")) > 0.0:
h.add_inplane_bfield(b=get("inplaneb"), phi=get("inplaneb_phi"))
# mu,ml = get("mAB_upper"),get("mAB_lower") # get the masses
# h.add_sublattice_imbalance(lambda r: mu*(r[2]>0.)) # upper mass
# h.add_sublattice_imbalance(lambda r: ml*(r[2]<0.)) # lower mass
efield = get("interlayer_bias")
def bias(r):
if r[2] < 0.0: return efield
else: return -efield
h.shift_fermi(bias)
if h.has_spin:
h.add_zeeman([get("Bx"), get("By"), get("Bz")]) # Zeeman fields
h.add_rashba(get("rashba")) # Rashba field
h.add_antiferromagnetism(get("mAF")) # AF order
h.add_kane_mele(get("kanemele")) # intrinsic SOC
h.shift_fermi(get("fermi")) # shift fermi energy
if is_checked("set_half_filling"): h.set_filling(nk=2)
if False:
h.add_swave(get("swave"))
if False:
if h.has_eh:
print("SCF not implemented with Nambu")
raise
if False:
custom_scf(h) # create the tb90.in
# else:
# h.write("hamiltonian.in")
klist.default(g, nk=int(get("nkpoints"))) # write klist
# klist.tr_path(nk=int(get("nkpoints"))) # write klist
return h
def initialize():
""" Initialize the calculation"""
def check(name):
if abs(get(name)) > 0.0: return True
else: return False
g = get_geometry() # get the geometry
if check("strain"): # custom function
dfun = get("strain") # get function
def fun(r1, r2): # function to compute distance
dr = r1 - r2
dr2 = dr.dot(dr) # distance
if 0.9 < dr2 < 1.1:
if 0.9 < abs(dr[2]) < 1.1: return 1.0 + dfun # first neighbor
return 1.0
else:
return 0.0
h = g.get_hamiltonian(fun) # get the Hamiltonian
else:
h = g.get_hamiltonian(has_spin=True)
j = np.array([get("Bx"), get("By"), get("Bz")])
h.add_zeeman(j) # Zeeman field
h.add_sublattice_imbalance(get("mAB")) # sublattice imbalance
if check("rashba"): h.add_rashba(get("rashba")) # Rashba field
h.add_antiferromagnetism(get("mAF")) # AF order
h.add_crystal_field(qtwrap.get("crystalfield"))
h.shift_fermi(get("fermi")) # shift fermi energy
if abs(get("kanemele")) > 0.0:
h.add_kane_mele(get("kanemele")) # intrinsic SOC
if abs(get("antikanemele")) > 0.0:
h.add_anti_kane_mele(get("antikanemele"))
if abs(get("haldane")) > 0.0:
h.add_haldane(get("haldane")) # intrinsic SOC
if abs(get("antihaldane")) > 0.0: h.add_antihaldane(get("antihaldane"))
# h.add_peierls(get("peierls")) # shift fermi energy
if abs(get("inplaneb")) > 0.0:
h.add_inplane_bfield(b=get("inplaneb"), phi=get("inplaneb_phi"))
if abs(get("swave")) > 0.0:
h = h.get_multicell()
special_pairing(h)
return h
def initialize():
""" Initialize the calculation"""
g = get_geometry() # get the geometry
t2, t3 = get("t2"), get("t3") # get hoppings
if t2 != 0.0 or t3 != 0.0:
ts = [1., t2, t3]
fm = specialhopping.neighbor_hopping_matrix(g, ts)
h = g.get_hamiltonian(mgenerator=fm, has_spin=True)
else:
h = g.get_hamiltonian(has_spin=True)
h.add_zeeman([get("Bx"), get("By"), get("Bz")]) # Zeeman fields
h.add_sublattice_imbalance(get("mAB")) # sublattice imbalance
h.add_rashba(get("rashba")) # Rashba field
h.add_antiferromagnetism(get("mAF")) # AF order
h.add_crystal_field(qtwrap.get("crystalfield")) # add magnetic field
h.shift_fermi(get("fermi")) # shift fermi energy
h.add_kane_mele(get("kanemele")) # intrinsic SOC
h.add_haldane(get("haldane")) # intrinsic SOC
h.add_antihaldane(get("antihaldane"))
h.add_peierls(get("peierls")) # magnetic field
if get("swave") != 0.0: h.add_swave(get("swave"))
return h
def initialize():
""" Initialize the calculation"""
t0 = time.clock()
os.system("rm SELECTED_ATOMS.INFO") # remove the file for the DOS
g = get_geometry0d() # get the geometry
h = hamiltonians.hamiltonian(g) # get the hamiltonian
h.has_spin = False # spin treatment
if h.has_spin: # spinful hamiltonian
print("Spinful hamiltonian, DO NOT USE VERY LARGE ISLANDS!!!")
h.is_sparse = False
h.first_neighbors() # first neighbor hoppin
h.add_zeeman([get("Bx"), get("By"), get("Bz")]) # Zeeman fields
if abs(get("rashba")) > 0.0:
h.add_rashba(get("rashba")) # Rashba field
h.add_antiferromagnetism(get("mAF")) # AF order
if abs(get("kanemele")) > 0.0:
h.add_kane_mele(get("kanemele")) # intrinsic SOC
h.shift_fermi(get("fermi")) # shift fermi energy
h.turn_sparse() # turn it sparse
else: # spinless treatment
h.is_sparse = True
print("Spinless hamiltonian")
h.first_neighbors() # first neighbor hopping
h.add_sublattice_imbalance(get("mAB")) # sublattice imbalance
h.add_peierls(get("peierls")) # add magnetic field
h.add_crystal_field(qtwrap.get("crystalfield")) # add magnetic field
if get("haldane") != 0.0:
h.add_haldane(get("haldane")) # add Haldane coupling
if get("edge_potential") != 0.0: # if there is edge potential
edgesites = edge_atoms(h.geometry) # get the edge atoms
h.shift_fermi(get("edge_potential") * edgesites) # add onsites
# part for bilayer systems
#####
print("Time spent in creating the Hamiltonian =", time.clock() - t0)
h.geometry.write()
h.save() # save the Hamiltonian
