Example of a 2J solar cell calculated with the PDD solver ========================================================= .. image:: PDD_carrier_density.png :width: 40% .. image:: PDD_IV.png :width: 40% .. image:: PDD_qe.png :width: 40% .. code-block:: Python import matplotlib.pyplot as plt import numpy as np from solcore.solar_cell import SolarCell, default_GaAs from solcore.structure import Layer, Junction from solcore import si from solcore import material from solcore.light_source import LightSource from solcore.solar_cell_solver import solar_cell_solver T = 298 substrate = material('GaAs')(T=T) def AlGaAs(T): # We create the other materials we need for the device window = material('AlGaAs')(T=T, Na=5e24, Al=0.8) p_AlGaAs = material('AlGaAs')(T=T, Na=1e24, Al=0.4) n_AlGaAs = material('AlGaAs')(T=T, Nd=8e22, Al=0.4) bsf = material('AlGaAs')(T=T, Nd=2e24, Al=0.6) output = Junction([Layer(width=si('30nm'), material=window, role="Window"), Layer(width=si('150nm'), material=p_AlGaAs, role="Emitter"), Layer(width=si('1000nm'), material=n_AlGaAs, role="Base"), Layer(width=si('200nm'), material=bsf, role="BSF")], sn=1e6, sp=1e6, T=T, kind='PDD') return output my_solar_cell = SolarCell([AlGaAs(T), default_GaAs(T)], T=T, R_series=0, substrate=substrate) Vin = np.linspace(-2, 2.61, 201) V = np.linspace(0, 2.6, 300) wl = np.linspace(350, 1000, 301) * 1e-9 light_source = LightSource(source_type='standard', version='AM1.5g', x=wl, output_units='photon_flux_per_m', concentration=1) # We calculate the IV curve under illumination solar_cell_solver(my_solar_cell, 'iv', user_options={'T_ambient': T, 'db_mode': 'boltzmann', 'voltages': V, 'light_iv': True, 'wavelength': wl, 'optics_method': 'BL', 'mpp': True, 'internal_voltages': Vin, 'light_source': light_source}) # We can plot the electron and hole densities in equilibrium and at short circuit, both calculated automatically # before calculating the IV curve plt.figure(1) for j in my_solar_cell.junction_indices: zz = my_solar_cell[j].short_circuit_data.Bandstructure['x'] + my_solar_cell[j].offset n = my_solar_cell[j].short_circuit_data.Bandstructure['n'] p = my_solar_cell[j].short_circuit_data.Bandstructure['p'] plt.semilogy(zz, n, 'b') plt.semilogy(zz, p, 'r') zz = my_solar_cell[j].equilibrium_data.Bandstructure['x'] + my_solar_cell[j].offset n = my_solar_cell[j].equilibrium_data.Bandstructure['n'] p = my_solar_cell[j].equilibrium_data.Bandstructure['p'] plt.semilogy(zz, n, 'b--') plt.semilogy(zz, p, 'r--') plt.xlabel('Position (m)') plt.ylabel('Carrier density (m\$^{-3}\$)') # And the IV curves of the individual junctions and of the MJ device plt.figure(2) plt.plot(V, abs(my_solar_cell[0].iv(V)), 'b', label='AlGaAs') plt.plot(V, abs(my_solar_cell[1].iv(V)), 'r', label='GaAs') plt.plot(my_solar_cell.iv.IV[0], abs(my_solar_cell.iv.IV[1]), 'k', label='MJ') plt.legend() plt.xlim(0, 2.6) plt.ylim(0, 200) plt.xlabel('Bias (V)') plt.ylabel('Current (A/m\$^2}\$)') # Now we calculate the quantum efficiency solar_cell_solver(my_solar_cell, 'qe', user_options={'T_ambient': T, 'db_mode': 'boltzmann', 'voltages': V, 'light_iv': True, 'wavelength': wl, 'optics_method': 'BL', 'mpp': True, 'internal_voltages': Vin, 'light_source': light_source}) plt.figure(3) plt.plot(wl * 1e9, my_solar_cell[0].eqe(wl), 'b', label='AlGaAs') plt.plot(wl * 1e9, my_solar_cell[1].eqe(wl), 'r', label='GaAs') plt.xlabel('Wavelength (nm)') plt.ylabel('EQE') plt.show()