def system(N=0,s=1e-18*1e4):
# dimensions of the system
Lx = 3e-6*1e2 #[m]
Ly = 3e-6*1e2 #[m]
# extent of the junction from the left contact [m]
junction = .1e-6*1e2
## initial: 60,50,10... 40,20,40
# Mesh
x = np.concatenate((np.linspace(0,.2e-6*1e2, 30, endpoint=False),
np.linspace(0.2e-6*1e2, 1.4e-6*1e2, 60, endpoint=False),
np.linspace(1.4e-6*1e2, 2.7e-6*1e2, 60, endpoint=False),
np.linspace(2.7e-6*1e2, Lx-0.02e-6*1e2, 30, endpoint=False),
np.linspace(Lx-0.02e-6*1e2, Lx, 10)))
#y = np.linspace(0, 1.25e-6, 40)
y = np.concatenate((np.linspace(0, 1.25e-6*1e2, 60, endpoint=False),
np.linspace(1.25e-6*1e2, 1.75e-6*1e2, 50, endpoint=False),
np.linspace(1.75e-6*1e2, Ly, 60)))
# Create a system
sys = sesame.Builder(x, y)
def region(pos):
x, y = pos
return x < junction
# Add the donors
nD = 1e17 # [m^-3]
sys.add_donor(nD, region)
# Add the acceptors
region2 = lambda pos: 1 - region(pos)
nA = 1e15 # [m^-3]
sys.add_acceptor(nA, region2)
# Use perfectly selective contacts
sys.contact_type('Ohmic','Ohmic')
#Sn_left, Sp_left, Sn_right, Sp_right = 1e50, 0, 0, 1e50
Sn_left, Sp_left, Sn_right, Sp_right = 1e50, 1e50, 1e50, 1e50
sys.contact_S(Sn_left, Sp_left, Sn_right, Sp_right)
Nc = 8e17
Nv = 1.8e19
q = 1.60217662*1e-19
kb = 1.38064852*1e-23
t = 300
vt = kb*t/q
# Dictionary with the material parameters
mat = {'Nc':Nc, 'Nv':Nv, 'Eg':1.5, 'epsilon':9.4, 'Et': 0*vt*np.log(Nc/Nv),
'mu_e':320, 'mu_h':40, 'tau_e':10*1e-9, 'tau_h':10*1e-9}
# Add the material to the system
sys.add_material(mat)
# gap state characteristics
#s = 1e-24 # trap capture cross section [m^2]
E = 0.4 + .5*vt*np.log(Nc/Nv) # energy of gap state (eV) from midgap
# Specify the two points that make the line containing additional charges
p1 = (.1e-6*1e2, 1.5*1e-6*1e2) #[m]
p2 = (2.9e-6*1e2, 1.5*1e-6*1e2) #[m]
# Pass the information to the system
sys.add_line_defects([p1, p2], N, s, E=E, transition=(1,0))
sys.add_line_defects([p1, p2], N, s, E=E, transition=(0,-1))
return sys
def runTest7():
L = 4e-4 # length of the system in the x-direction [m]
dd = .05e-4
Ly = 2e-4
# Mesh
x = np.concatenate(
(np.linspace(0, 1e-4 - dd, 70, endpoint=False),
np.linspace(1e-4 - dd, 1e-4 + dd, 20, endpoint=False),
np.linspace(1e-4 + dd, 3e-4 - dd, 140, endpoint=False),
np.linspace(3e-4 - dd, 3e-4 + dd, 20,
endpoint=False), np.linspace(3e-4 + dd, L, 70)))
y = np.concatenate(
(np.linspace(0, 1e-4 - dd, 70, endpoint=False),
np.linspace(1e-4 - dd, 1e-4 + dd, 20,
endpoint=False), np.linspace(1e-4 + dd, 2e-4, 70)))
#x = np.linspace(0,L, 1000)
# Create a system
sys = sesame.Builder(x, y)
tau = 1e-8
vt = 0.025851991024560
Nc1 = 1e17
Nv1 = 1e18
Nc2 = 1e17
Nv2 = 1e18
# Dictionary with the material parameters
mat1 = {
'Nc': Nc1,
'Nv': Nv1,
'Eg': 1.,
'epsilon': 10,
'Et': 0,
'mu_e': 100,
'mu_h': 40,
'tau_e': tau,
'tau_h': tau,
'affinity': 4.15
}
mat2 = {
'Nc': Nc2,
'Nv': Nv2,
'Eg': 1.1,
'epsilon': 100,
'Et': 0,
'mu_e': 100,
'mu_h': 40,
'tau_e': tau,
'tau_h': tau,
'affinity': 4.05
}
junction = 2e-4 # extent of the junction from the left contact [m]
def region1(pos):
x, y = pos
val = x <= 1e-4
return val
def region2(pos):
x, y = pos
val = (x > 1e-4) & (x < 3e-4) & (y >= 1e-4)
return val
def region3(pos):
x, y = pos
val = (x > 1e-4) & (x < 3e-4) & (y < 1e-4)
return val
def region4(pos):
x, y = pos
val = x >= 3e-4
return val
# Add the material to the system
sys.add_material(mat1, region1)
sys.add_material(mat1, region2)
sys.add_material(mat2, region3)
sys.add_material(mat2, region4)
# Add the donors
nD1 = 1e15 # [cm^-3]
sys.add_donor(nD1, region1)
sys.add_donor(nD1, region2)
nD2 = 1e15 # [cm^-3]
sys.add_acceptor(nD2, region3)
sys.add_acceptor(nD2, region4)
# Define the surface recombination velocities for electrons and holes [m/s]
sys.contact_type('Ohmic', 'Ohmic')
SS = 1e50
Sn_left, Sp_left, Sn_right, Sp_right = SS, SS, SS, SS
sys.contact_S(Sn_left, Sp_left, Sn_right, Sp_right)
# Electrostatic potential dimensionless
solution = sesame.solve_equilibrium(sys, periodic_bcs=False, verbose=False)
veq = np.copy(solution['v'])
solution.update({
'x': sys.xpts,
'y': sys.ypts,
'chi': sys.bl,
'eg': sys.Eg,
'Nc': sys.Nc,
'Nv': sys.Nv,
'epsilon': sys.epsilon
})
# IV curve
solution.update({
'efn': np.zeros((sys.nx * sys.ny, )),
'efp': np.zeros((sys.nx * sys.ny, ))
})
G = 1 * 1e18
f = lambda x, y: G
sys.generation(f)
solution = sesame.solve(sys,
solution,
maxiter=5000,
periodic_bcs=False,
verbose=False)
az = sesame.Analyzer(sys, solution)
tj = -az.full_current()
voltages = np.linspace(.0, .8, 9)
result = solution
# sites of the right contact
nx = sys.nx
s = [nx - 1 + j * nx + k * nx * sys.ny for k in range(sys.nz) \
for j in range(sys.ny)]
# sign of the voltage to apply
if sys.rho[nx - 1] < 0:
q = 1
else:
q = -1
j = []
# Loop over the applied potentials made dimensionless
Vapp = voltages / sys.scaling.energy
for idx, vapp in enumerate(Vapp):
# Apply the voltage on the right contact
result['v'][s] = veq[s] + q * vapp
# Call the Drift Diffusion Poisson solver
result = sesame.solve(sys,
result,
maxiter=1000,
periodic_bcs=False,
verbose=False)
# Compute current
az = sesame.Analyzer(sys, result)
tj = az.full_current() * sys.scaling.current * sys.scaling.length / (
2e-4)
j.append(tj)
jcomsol = np.array([
0.50272, 0.48515, 0.40623, -0.16696, -5.1204, -58.859, -819.11,
-7024.4, -27657
])
jcomsol = jcomsol * 1e-4
error = np.max(
np.abs(
(jcomsol - np.transpose(j)) / (.5 * (jcomsol + np.transpose(j)))))
def runTest2():
L = 4e-6*1e2 # length of the system in the x-direction [m]
dd = .005e-6*1e2
# Mesh
x = np.concatenate((np.linspace(0,L/2-dd, 100, endpoint=False),
np.linspace(L/2-dd, L/2+dd, 20, endpoint=False),
np.linspace(L/2+dd,L, 100)))
# Create a system
sys = sesame.Builder(x, input_length='cm')
tau = 1e8
vt = 0.025851991024560;
Nc1 = 2.2*1e18
Nv1 = 2.2*1e18
Nc2 = 2.2*1e18
Nv2 = 2.2*1e18
# Dictionary with the material parameters
mat1 = {'Nc':Nc1, 'Nv':Nv1, 'Eg':1.5, 'epsilon':1000, 'Et': 0,
'mu_e':100, 'mu_h':40, 'tau_e':tau, 'tau_h':tau,
'band_offset': 4.05}
mat2 = {'Nc':Nc2, 'Nv':Nv2, 'Eg':1.5, 'epsilon':10000, 'Et': 0,
'mu_e':100, 'mu_h':40, 'tau_e':tau, 'tau_h':tau,
'band_offset': 4.05}
junction = 2e-6*1e2 # extent of the junction from the left contact [m]
def region1(pos):
return pos < junction
# Add the acceptors
region2 = lambda pos: 1 - region1(pos)
# Add the material to the system
sys.add_material(mat1, region1)
sys.add_material(mat2, region2)
# Define Ohmic contacts
sys.contact_type('Ohmic', 'Ohmic')
# Add the donors
nD1 = 1e15 # [m^-3]
sys.add_donor(nD1, region1)
nD2 = 1e15 # [m^-3]
sys.add_acceptor(nD2, region2)
# Define the surface recombination velocities for electrons and holes [m/s]
SS = 1e50
Sn_left, Sp_left, Sn_right, Sp_right = SS, SS, SS, SS
sys.contact_S(Sn_left, Sp_left, Sn_right, Sp_right)
# Electrostatic potential dimensionless
solution = sesame.solve_equilibrium(sys, verbose=False)
veq = np.copy(solution['v'])
G = 1*1e24*1e-6
f = lambda x: G
sys.generation(f)
solution = sesame.solve(sys, solution, verbose=False)
solution.update({'x': sys.xpts, 'chi': sys.bl, 'eg': sys.Eg, 'Nc': sys.Nc, 'Nv': sys.Nv})
voltages = np.linspace(0, 0.9, 10)
result = solution
# sites of the right contact
nx = sys.nx
s = [nx-1 + j*nx + k*nx*sys.ny for k in range(sys.nz)\
for j in range(sys.ny)]
# sign of the voltage to apply
if sys.rho[nx-1] < 0:
q = 1
else:
q = -1
j = []
# Loop over the applied potentials made dimensionless
Vapp = voltages / sys.scaling.energy
for idx, vapp in enumerate(Vapp):
# Apply the voltage on the right contact
result['v'][s] = veq[s] + q*vapp
# Call the Drift Diffusion Poisson solver
result = sesame.solve(sys, result, maxiter=1000, verbose=False)
# Compute current
az = sesame.Analyzer(sys, result)
tj = az.full_current()* sys.scaling.current
j.append(tj)
jcomsol = np.array([0.55569,0.54937,0.5423,0.53436,0.52535,0.51499,0.50217,0.4622,-0.47448,-31.281])
jcomsol = jcomsol * 1e-4
error = np.max(np.abs((jcomsol-np.transpose(j))/(.5*(jcomsol+np.transpose(j)))))
print("error = {0}".format(error))
t1 = 25*1e-7 # thickness of CdS
t2 = 4*1e-4 # thickness of CdTe
# Heterojunctions require dense mesh near the interface
dd = 1e-7 # 2*dd is the distance over which mesh is refined
# Define the mesh
x = np.concatenate((np.linspace(0, dd, 10, endpoint=False), # L contact interface
np.linspace(dd, t1-dd, 50, endpoint=False), # material 1
np.linspace(t1 - dd, t1 + dd, 10, endpoint=False), # interface 1
np.linspace(t1 + dd, (t1+t2) - dd, 100, endpoint=False), # material 2
np.linspace((t1+t2) - dd, (t1+t2), 10))) # R contact interface
# Build system
sys = sesame.Builder(x)
# CdS material dictionary
CdS = {'Nc': 2.2e18, 'Nv':1.8e19, 'Eg':2.4, 'epsilon':10, 'Et': 0,
'mu_e':100, 'mu_h':25, 'tau_e':1e-8, 'tau_h':1e-13,
'affinity': 4.}
# CdTe material dictionary
CdTe = {'Nc': 8e17, 'Nv': 1.8e19, 'Eg':1.5, 'epsilon':9.4, 'Et': 0,
'mu_e':320, 'mu_h':40, 'tau_e':5e-9, 'tau_h':5e-9,
'affinity': 3.9}
# CdS region
CdS_region = lambda pos: pos[0]<=t1
# CdTe region
CdTe_region = lambda pos: pos[0]>t1
def system(params):
# we assume the params are given in order: [rho_GB, E_GB, S_GB, tau]
rho_GB = params[0]
E_GB = params[1]
S_GB = params[2]
tau = params[3]
# Dimensions of the system
Lx = 3e-4 # [cm]
Ly = 3e-4 # [cm]
# Mesh
x = np.concatenate(
(np.linspace(0, 0.2e-4, 30, endpoint=False),
np.linspace(0.2e-4, 1.4e-4, 60, endpoint=False),
np.linspace(1.4e-4, 2.7e-4, 60, endpoint=False),
np.linspace(2.7e-4, 2.98e-4, 30,
endpoint=False), np.linspace(2.98e-4, Lx, 10)))
y = np.concatenate(
(np.linspace(0, 1.25e-4, 60, endpoint=False),
np.linspace(1.25e-4, 1.75e-4, 50,
endpoint=False), np.linspace(1.75e-4, Ly, 60)))
# Create a system
sys = sesame.Builder(x, y)
# Dictionary with the material parameters
mat = {
'Nc': 8e17,
'Nv': 1.8e19,
'Eg': 1.5,
'epsilon': 9.4,
'Et': 0,
'mu_e': 320,
'mu_h': 40,
'tau_e': tau,
'tau_h': tau
}
# Add the material to the system
sys.add_material(mat)
# Extent of the junction from the left contact [cm]
junction = .1e-4 # [cm]
# Define a function specifiying the n-type region
def region1(pos):
x, y = pos
return x < junction
# Define a function specifiying the p-type region
def region2(pos):
x, y = pos
return x >= junction
# Add the donors
nD = 1e17 # Donor density [cm^-3]
sys.add_donor(nD, region1)
# Add the acceptors
nA = 1e15 # Acceptor density [cm^-3]
sys.add_acceptor(nA, region2)
# Define contacts: CdS and CdTe contacts are Ohmic
sys.contact_type('Ohmic', 'Ohmic')
# Define the surface recombination velocities for electrons and holes [cm/s]
Sn_left, Sp_left, Sn_right, Sp_right = 1e7, 1e7, 1e7, 1e7
# This function specifies the simulation contact recombination velocity [cm/s]
sys.contact_S(Sn_left, Sp_left, Sn_right, Sp_right)
# Specify the two points that make the line containing additional charges
p1 = (0.1e-4, 1.5e-4) # [cm]
p2 = (2.9e-4, 1.5e-4) # [cm]
# Add donor defect along GB
sys.add_defects([p1, p2], rho_GB, S_GB, E=E_GB, transition=(1, 0))
# Add acceptor defect along GB
sys.add_defects([p1, p2], rho_GB, S_GB, E=E_GB, transition=(0, -1))
return sys
# extent of the junction from the left contact [cm]
junction = .1e-4 # [cm]
# Mesh
x = np.concatenate((np.linspace(0, .2e-4, 30, endpoint=False),
np.linspace(0.2e-4, 1.4e-4, 60, endpoint=False),
np.linspace(1.4e-4, 2.9e-4, 70,
endpoint=False), np.linspace(2.9e-4, 3e-4,
10)))
y = np.concatenate((np.linspace(0, 1.75e-4, 50, endpoint=False),
np.linspace(1.75e-4, 2.75e-4, 50,
endpoint=False), np.linspace(2.75e-4, Ly, 50)))
# Create a system
sys = sesame.Builder(x, y, periodic=False)
# Dictionary with the material parameters
mat = {
'Nc': 8e17,
'Nv': 1.8e19,
'Eg': 1.5,
'epsilon': 9.4,
'Et': 0,
'mu_e': 320,
'mu_h': 40,
'tau_e': 10 * 1e-9,
'tau_h': 10 * 1e-9,
'B': 1e-10
}
def runTest1():
L = 3e-4 # length of the system in the x-direction [cm]
dd = 1e-7*1e2
# Mesh
x = np.concatenate((np.linspace(0,5e-7*1e2-dd,50, endpoint=False),
np.linspace(5e-7*1e2-dd,5e-7*1e2+dd,20, endpoint=False),
np.linspace(5e-7*1e2+dd,1e-6*1e2, 100, endpoint=False),
np.linspace(1e-6*1e2, L, 200)))
# Create a system
sys = sesame.Builder(x,input_length='cm')
tau = 1e-8
vt = 0.025851991024560
Nc1 = 8*1e17
Nv1 = 1.8*1e19
Nc2 = 8*1e17
Nv2 = 1.8*1e19
# Dictionary with the material parameters
mat1 = {'Nc':Nc1, 'Nv':Nv1, 'Eg':2.4, 'epsilon':10, 'Et': 0,
'mu_e':320, 'mu_h':40, 'tau_e':tau, 'tau_h':tau,
'affinity': 4.15}
mat2 = {'Nc':Nc2, 'Nv':Nv2, 'Eg':1.5, 'epsilon':10, 'Et': 0,
'mu_e':320, 'mu_h':40, 'tau_e':tau, 'tau_h':tau,
'affinity': 4.05}
junction = 5e-7*1e2 # extent of the junction from the left contact [m]
def region1(pos):
x = pos
return x < junction
# Add the acceptors
region2 = lambda pos: 1 - region1(pos)
# Add the material to the system
sys.add_material(mat1, region1)
sys.add_material(mat2, region2)
# Add the donors
nD1 = 1e17 # [cm^-3]
sys.add_donor(nD1, region1)
nD2 = 1e15 # [cm^-3]
sys.add_acceptor(nD2, region2)
# Define Ohmic contacts
sys.contact_type('Ohmic', 'Ohmic')
# Define the surface recombination velocities for electrons and holes [m/s]
SS = 1e50*1e2
Sn_left, Sp_left, Sn_right, Sp_right = SS, SS, SS, SS
sys.contact_S(Sn_left, Sp_left, Sn_right, Sp_right)
solution = sesame.solve(sys, compute='Poisson', verbose=False)
veq = np.copy(solution['v'])
G = 1*1e24*1e-6
f = lambda x: G
sys.generation(f)
solution = sesame.solve(sys, guess=solution, verbose=False)
solution.update({'x': sys.xpts, 'chi': sys.bl, 'eg': sys.Eg, 'Nc': sys.Nc, 'Nv': sys.Nv})
voltages = np.linspace(0, 0.8, 9)
result = solution
# sites of the right contact
nx = sys.nx
s = [nx-1 + j*nx for j in range(sys.ny)]
# sign of the voltage to apply
if sys.rho[nx-1] < 0:
q = 1
else:
q = -1
j = []
# Loop over the applied potentials made dimensionless
Vapp = voltages / sys.scaling.energy
for idx, vapp in enumerate(Vapp):
# Apply the voltage on the right contact
result['v'][s] = veq[s] + q*vapp
# Call the Drift Diffusion Poisson solver
result = sesame.solve(sys, guess=result, maxiter=1000, verbose=False)
# Compute current
az = sesame.Analyzer(sys, result)
tj = az.full_current()* sys.scaling.current
j.append(tj)
jcomsol = np.array([0.32117,0.31672,0.31198,0.30683,0.30031,0.28562,0.20949,-0.39374,-7.0681])
jcomsol = jcomsol * 1e-4 # converting to A/cm^2
error = np.max(np.abs((jcomsol-np.transpose(j))/(.5*(jcomsol+np.transpose(j)))))
print("error = {0}".format(error))
def runTest8():
L = 4e-4 # length of the system in the x-direction [m]
dd = .05e-4
Ly = 2e-4
# Mesh
x = np.concatenate(
(np.linspace(0, 1e-4 - dd, 70, endpoint=False),
np.linspace(1e-4 - dd, 1e-4 + dd, 20, endpoint=False),
np.linspace(1e-4 + dd, 3e-4 - dd, 140, endpoint=False),
np.linspace(3e-4 - dd, 3e-4 + dd, 20,
endpoint=False), np.linspace(3e-4 + dd, L, 70)))
y = np.concatenate(
(np.linspace(0, 1e-4 - dd, 70, endpoint=False),
np.linspace(1e-4 - dd, 1e-4 + dd, 20,
endpoint=False), np.linspace(1e-4 + dd, 2e-4, 70)))
# Create a system
sys = sesame.Builder(x, y)
tau = 1e-8
vt = 0.025851991024560
Nc1 = 1e17
Nv1 = 1e18
Nc2 = 1e17
Nv2 = 1e18
# Dictionary with the material parameters
mat1 = {
'Nc': Nc1,
'Nv': Nv1,
'Eg': 1.,
'epsilon': 10,
'Et': 0,
'mu_e': 100,
'mu_h': 40,
'tau_e': tau,
'tau_h': tau,
'affinity': 4.15
}
mat2 = {
'Nc': Nc2,
'Nv': Nv2,
'Eg': 1.1,
'epsilon': 100,
'Et': 0,
'mu_e': 100,
'mu_h': 40,
'tau_e': tau,
'tau_h': tau,
'affinity': 4.05
}
junction = 2e-4 # extent of the junction from the left contact [m]
def region1(pos):
x, y = pos
val = x <= 1e-4
return val
def region2(pos):
x, y = pos
val = (x > 1e-4) & (x < 3e-4) & (y >= 1e-4)
return val
def region3(pos):
x, y = pos
val = (x > 1e-4) & (x < 3e-4) & (y < 1e-4)
return val
def region4(pos):
x, y = pos
val = x >= 3e-4
return val
# Add the material to the system
sys.add_material(mat1, region1)
sys.add_material(mat1, region2)
sys.add_material(mat2, region3)
sys.add_material(mat2, region4)
# Add the donors
nD1 = 1e15 # [cm^-3]
sys.add_donor(nD1, region1)
sys.add_donor(nD1, region2)
nD2 = 1e15 # [cm^-3]
sys.add_acceptor(nD2, region3)
sys.add_acceptor(nD2, region4)
# Define the surface recombination velocities for electrons and holes [m/s]
sys.contact_type('Ohmic', 'Ohmic')
SS = 1e50
Sn_left, Sp_left, Sn_right, Sp_right = SS, SS, SS, SS
sys.contact_S(Sn_left, Sp_left, Sn_right, Sp_right)
# Electrostatic potential dimensionless
solution = sesame.solve(sys,
compute='Poisson',
periodic_bcs=False,
verbose=False)
veq = np.copy(solution['v'])
solution.update({
'x': sys.xpts,
'y': sys.ypts,
'chi': sys.bl,
'eg': sys.Eg,
'Nc': sys.Nc,
'Nv': sys.Nv,
'epsilon': sys.epsilon
})
# IV curve
solution.update({
'efn': np.zeros((sys.nx * sys.ny, )),
'efp': np.zeros((sys.nx * sys.ny, ))
})
G = 1 * 1e18
f = lambda x, y: G
sys.generation(f)
solution = sesame.solve(sys,
guess=solution,
maxiter=5000,
periodic_bcs=True,
verbose=False)
az = sesame.Analyzer(sys, solution)
tj = -az.full_current()
voltages = np.linspace(.0, .8, 9)
result = solution
# sites of the right contact
nx = sys.nx
s = [nx - 1 + j * nx for j in range(sys.ny)]
# sign of the voltage to apply
if sys.rho[nx - 1] < 0:
q = 1
else:
q = -1
j = []
# Loop over the applied potentials made dimensionless
Vapp = voltages / sys.scaling.energy
for idx, vapp in enumerate(Vapp):
# Apply the voltage on the right contact
result['v'][s] = veq[s] + q * vapp
# Call the Drift Diffusion Poisson solver
result = sesame.solve(sys,
guess=result,
maxiter=1000,
periodic_bcs=True,
verbose=False)
# Compute current
az = sesame.Analyzer(sys, result)
tj = az.full_current() * sys.scaling.current * sys.scaling.length / (
2e-4)
j.append(tj)
jSesame_12_4_2017 = np.array([
0.51880926865443222, 0.49724822874328478, 0.38634212450640715,
-0.41864449697811151, -7.1679242861918242, -76.107867495994327,
-919.58279216747349, -7114.3078754855478, -28453.412760553809
])
jSesame_12_4_2017 = jSesame_12_4_2017 * 1e-4
error = np.max(
np.abs((jSesame_12_4_2017 - np.transpose(j)) /
(.5 * (jSesame_12_4_2017 + np.transpose(j)))))
print("error = {0}".format(error))
import sesame
import numpy as np
L = 3e-4 # length of the system in the x-direction [cm]
# Mesh
xpts = np.concatenate(
(np.linspace(0, 1.2e-4, 100, endpoint=False), np.linspace(1.2e-4, L, 50)))
# Create a system
sys = sesame.Builder(xpts)
# Dictionary with the material parameters
material = {
'Nc': 1e19,
'Nv': 1e19,
'Eg': 1.5,
'affinity': 3.9,
'epsilon': 9.4,
'mu_e': 100,
'mu_h': 100,
'tau_e': 10e-9,
'tau_h': 10e-9,
'Et': 0
}
# Add the material to the system
sys.add_material(material)
junction = 50e-7 # extent of the junction from the left contact [cm]
