def __init__(self, N, js, Es, ts, Us, Ws=None, gs=None, parasite=0):
model = scattering.Model(
Es=Es,
links=[(i, (i + 1) % N, ts[i]) for i in range(N)],
Us=Us,
W=Ws)
if gs is None:
gs = normalize([1, 1])
channels = []
channels.append(scattering.Channel(site=js[0], strength=gs[0]))
channels.append(scattering.Channel(site=js[1], strength=gs[1]))
parasites = []
if parasite > 0:
parasites = [scattering.Channel(site=i, strength=parasite) for i in range(N)]
scattering.Setup.__init__(self, model, channels, parasites)
self.info = {
'N': N,
'js': js,
'Es': Es,
'ts': ts,
'Us': Us,
'gs': gs,
'parasite': parasite,
'name': 'ring'
}
def __init__(self, N, js, Es, ts, Us, gs=None, parasite=0):
"""
Generate a scattering setup with two main channels connected to a chain of BH sites.
O - O - O - O - .. - O
0 1 2 3 N
Parameters
----------
N : int
Number of sites
js : list
List of the two sites which the two channels connect to
Es : list
List of onsite energies
ts : list
List of values for each hopping, [t0:1, t1:2, ... tN-1:N]
Us : list
List of values for onsite interaction
gs: list
List of coupling strengths for each channel. Defaults to normalized.
parasite : float
Additional uniform decay constant. Defaults to 0.
"""
model = scattering.Model(Es=Es,
links=[(i, i + 1, ts[i])
for i in range(N - 1)],
Us=Us)
if gs is None:
gs = normalize([1, 1])
channels = []
channels.append(scattering.Channel(site=js[0], strength=gs[0]))
channels.append(scattering.Channel(site=js[1], strength=gs[1]))
parasites = []
if parasite > 0:
parasites = [
scattering.Channel(site=i, strength=parasite) for i in range(N)
]
scattering.Setup.__init__(self, model, channels, parasites)
self.info = {
'N': N,
'js': js,
'Es': Es,
'ts': ts if len(ts) > 0 else [0],
'Us': Us,
'gs': gs,
'parasite': parasite,
'name': 'chain'
}
def __init__(self, L, W, H, js, Es, ts, Us, gs=None, parasite=0):
N = W * L * H # number of sites
# construct links list
links = []
i = 0
for x in xrange(L):
for y in xrange(W):
for z in xrange(H):
n = x + L * y + W * L * z
if x < L - 1:
links.append([n, n + 1, ts[i]])
if y < W - 1:
links.append([n, n + L, ts[i]])
if z < H - 1:
links.append([n, n + L * W, ts[i]])
i += 1
model = scattering.Model(Es=Es, links=links, Us=Us)
if gs is None:
gs = normalize([1, 1])
channels = []
channels.append(scattering.Channel(site=js[0], strength=gs[0]))
channels.append(scattering.Channel(site=js[1], strength=gs[1]))
parasites = []
if np.abs(parasite) > 0:
parasites = [
scattering.Channel(site=i, strength=parasite)
for i in xrange(N)
]
scattering.Setup.__init__(self, model, channels, parasites)
self.info = {
'N': N,
'L': L,
'W': W,
'H': H,
'js': js,
'Es': Es,
'ts': ts,
'Us': Us,
'gs': gs,
'parasite': parasite,
'name': 'cube'
}
def __init__(self, N, Es, ts, Us, Ws=None, xs=None, gs=None, parasite=0):
# defaults
Ws = np.zeros((N, N)) if Ws is None else Ws
xs = np.zeros((N, 1)) if xs is None else xs
# model
model = scattering.Model(Es=Es,
links=[(i, i + 1, ts[i])
for i in range(N - 1)],
Us=Us,
W=Ws)
# coupling strengths
if gs is None:
gs = normalize([1, 1])
# sites
sites = np.arange(0, N)
channels = []
channels.append(
scattering.Channel(sites=sites, strengths=gs, positions=xs))
channels.append(
scattering.Channel(sites=sites,
strengths=gs,
positions=-np.array(xs)))
parasites = None
if parasite > 0:
parasites = [
scattering.Channel(site=i, strength=parasite) for i in range(N)
]
scattering.Setup.__init__(self, model, channels, parasites)
self.info = {
'N': N,
'Es': Es,
'ts': ts,
'Us': Us,
'Ws': Ws,
'gs': gs,
'xs': xs,
'parasite': parasite,
'name': 'proximatechain'
}
def __init__(self, L, W, js, Es, ts, Us, gs=None, parasite=0):
links = []
i = 0
for x in range(L):
for y in range(W):
n = x + L * y
if x < L - 1:
links.append([n, n + 1, ts[i]])
i += 1
if y < W - 1:
links.append([n, n + L, ts[i]])
i += 1
model = scattering.Model(Es=Es, links=links, Us=Us)
if gs is None:
gs = normalize([1, 1])
channels = []
channels.append(scattering.Channel(site=js[0], strength=gs[0]))
channels.append(scattering.Channel(site=js[1], strength=gs[1]))
N = L * W
parasites = []
if parasite > 0:
parasites = [
scattering.Channel(site=i, strength=parasite) for i in range(N)
]
scattering.Setup.__init__(self, model, channels, parasites)
self.info = {}
self.info['N'] = W * L
self.info['L'] = L # length of chain
self.info['W'] = W
self.info['js'] = js
self.info['Es'] = Es
self.info['ts'] = ts
self.info['Us'] = Us
self.info['gs'] = gs
self.info['parasite'] = parasite
self.info['name'] = 'plane'