def guiding_electric_field():
# Create structure
st = TransferMatrix()
st.set_vacuum_wavelength(lam0)
st.add_layer(1.5 * lam0, air)
st.add_layer(lam0, si)
st.add_layer(1.5 * lam0, air)
st.info()
st.set_polarization('TM')
st.set_field('H')
st.set_leaky_or_guiding('guiding')
alpha = st.calc_guided_modes(normalised=True)
plt.figure()
for i, a in enumerate(alpha):
st.set_guided_mode(a)
result = st.calc_field_structure()
z = result['z']
# z = st.calc_z_to_lambda(z)
E = result['field']
# Normalise fields
# E /= max(E)
plt.plot(z, abs(E) ** 2, label=i)
for z in st.get_layer_boundaries()[:-1]:
# z = st.calc_z_to_lambda(z)
plt.axvline(x=z, color='k', lw=1, ls='--')
plt.legend(title='Mode index')
if SAVE:
plt.savefig('../Images/guided fields.png', dpi=300)
plt.show()
def mcgehee():
st = TransferMatrix()
st.add_layer(0, 1.4504)
st.add_layer(110, 1.7704 + 0.01161j)
st.add_layer(35, 1.4621 + 0.04426j)
st.add_layer(220, 2.12 + 0.3166016j)
st.add_layer(7, 2.095 + 2.3357j)
st.add_layer(200, 1.20252 + 7.25439j)
st.add_layer(0, 1.20252 + 7.25439j)
st.set_vacuum_wavelength(600)
st.set_polarization('s')
st.set_field('E')
st.set_incident_angle(0, units='degrees')
st.info()
# Do calculations
result = st.calc_field_structure()
z = result['z']
y = result['field_squared']
# Plot results
plt.figure()
plt.plot(z, y)
for z in st.get_layer_boundaries()[:-1]:
plt.axvline(x=z, color='k', lw=2)
plt.xlabel('Position in Device (nm)')
plt.ylabel('Normalized |E|$^2$ Intensity ($|E(z)/E_0(0)|^2$)')
if SAVE:
plt.savefig('../Images/McGehee structure.png', dpi=300)
plt.show()