Add the effective DOS and the energy band gap models

tests/test_components/test_heat_charge.py

@@ -11,6 +11,8 @@
 from tidy3d.components.tcad.types import (
     AugerRecombination,
     CaugheyThomasMobility,
+    ConstantEffectiveDOS,
+    ConstantEnergyBandGap,
     SlotboomBandGapNarrowing,
 )
 from tidy3d.exceptions import DataError
@@ -39,9 +41,9 @@ class CHARGE_SIMULATION:
             permittivity=11.7,
             N_d=0,
             N_a=0,
-            N_c=2.86e19,
-            N_v=3.1e19,
-            E_g=1.11,
+            N_c=ConstantEffectiveDOS(N=2.86e19),
+            N_v=ConstantEffectiveDOS(N=3.1e19),
+            E_g=ConstantEnergyBandGap(eg=1.11),
             mobility_n=CaugheyThomasMobility(
                 mu_min=52.2,
                 mu=1471.0,
@@ -952,23 +954,30 @@ def Si_p(self):
         semiconductor = CHARGE_SIMULATION.intrinsic_Si.charge
         semiconductor = semiconductor.updated_copy(
             N_a=CHARGE_SIMULATION.acceptors,
+        )
+        return CHARGE_SIMULATION.intrinsic_Si.updated_copy(
+            charge=semiconductor,
+            heat=td.SolidMedium(conductivity=1),
             name="Si_p",
         )
-        return CHARGE_SIMULATION.intrinsic_Si.updated_copy(charge=semiconductor)
 
     @pytest.fixture(scope="class")
     def Si_n(self):
         semiconductor = CHARGE_SIMULATION.intrinsic_Si.charge
         semiconductor = semiconductor.updated_copy(
             N_d=CHARGE_SIMULATION.donors,
+        )
+        return CHARGE_SIMULATION.intrinsic_Si.updated_copy(
+            charge=semiconductor,
+            heat=td.SolidMedium(conductivity=1),
             name="Si_n",
         )
-        return CHARGE_SIMULATION.intrinsic_Si.updated_copy(charge=semiconductor)
 
     @pytest.fixture(scope="class")
     def SiO2(self):
         return td.MultiPhysicsMedium(
             charge=td.ChargeInsulatorMedium(permittivity=3.9),
+            heat=td.SolidMedium(conductivity=2),
             name="SiO2",
         )
 
@@ -1049,18 +1058,13 @@ def capacitance_global_mnt(self):
     # Define charge settings as fixtures within the class
     @pytest.fixture(scope="class")
     def charge_tolerance(self):
-        return td.IsothermalSteadyChargeDCAnalysis(
-            temperature=300,
-            tolerance_settings=td.ChargeToleranceSpec(rel_tol=1e5, abs_tol=1e3, max_iters=400),
-            fermi_dirac=True,
-        )
-
-    @pytest.fixture(scope="class")
-    def charge_dc_regime(self):
-        return td.DCVoltageSource(voltage=[1])
+        return td.ChargeToleranceSpec(rel_tol=1e5, abs_tol=1e3, max_iters=400)
 
     def test_charge_simulation(
         self,
+        Si_n,
+        Si_p,
+        SiO2,
         oxide,
         p_side,
         n_side,
@@ -1070,9 +1074,14 @@ def test_charge_simulation(
         bc_n,
         bc_p,
         charge_tolerance,
-        charge_dc_regime,
     ):
         """Ensure charge simulation produces the correct errors when needed."""
+        # NOTE: start tests with isothermal spec
+        isothermal_spec = td.IsothermalSteadyChargeDCAnalysis(
+            temperature=300,
+            tolerance_settings=charge_tolerance,
+            fermi_dirac=True,
+        )
         sim = td.HeatChargeSimulation(
             structures=[oxide, p_side, n_side],
             medium=td.MultiPhysicsMedium(
@@ -1083,7 +1092,7 @@ def test_charge_simulation(
             size=CHARGE_SIMULATION.sim_size,
             grid_spec=td.UniformUnstructuredGrid(dl=0.05),
             boundary_spec=[bc_n, bc_p],
-            analysis_spec=charge_tolerance,
+            analysis_spec=isothermal_spec,
         )
 
         # At least one ChargeSimulationMonitor should be added
@@ -1118,6 +1127,45 @@ def test_charge_simulation(
             )
             _ = sim.updated_copy(boundary_spec=[new_bc_p, bc_n])
 
+        # test non isothermal spec
+        non_isothermal_spec = td.SteadyChargeDCAnalysis(tolerance_settings=charge_tolerance)
+
+        sim = sim.updated_copy(analysis_spec=non_isothermal_spec)
+        with pytest.raises(pd.ValidationError):
+            # remove heat from mediums
+            new_structs = []
+            for struct in sim.structures:
+                new_structs.append(
+                    struct.updated_copy(medium=struct.medium.updated_copy(heat=None))
+                )
+            _ = sim.updated_copy(structures=new_structs)
+
+        with pytest.raises(pd.ValidationError):
+            # remove charge from mediums
+            new_structs = []
+            for struct in sim.structures:
+                new_structs.append(
+                    struct.updated_copy(medium=struct.medium.updated_copy(charge=None))
+                )
+            _ = sim.updated_copy(structures=new_structs)
+
+        with pytest.raises(pd.ValidationError):
+            # make sure there is at least one semiconductor
+            new_structs = []
+            for struct in sim.structures:
+                if isinstance(struct.medium.charge, td.SemiconductorMedium):
+                    new_structs.append(
+                        struct.updated_copy(
+                            medium=struct.medium.updated_copy(
+                                charge=td.ChargeInsulatorMedium(permittivity=1),
+                                heat=None,
+                            )
+                        )
+                    )
+                else:
+                    new_structs.append(struct)
+            _ = sim.updated_copy(structures=new_structs)
+
     def test_doping_distributions(self):
         """Test doping distributions."""
         # Implementation needed

tidy3d/__init__.py

@@ -20,6 +20,7 @@
 from tidy3d.components.spice.analysis.dc import (
     ChargeToleranceSpec,
     IsothermalSteadyChargeDCAnalysis,
+    SteadyChargeDCAnalysis,
 )
 from tidy3d.components.spice.sources.dc import DCCurrentSource, DCVoltageSource
 from tidy3d.components.spice.sources.types import VoltageSourceType
@@ -63,12 +64,19 @@
     AugerRecombination,
     CaugheyThomasMobility,
     ConstantMobilityModel,
+    ConstantEffectiveDOS,
+    ConstantEnergyBandGap,
+    QuadraticEnergyBandGap,
+    VarshniEnergyBandGap,
     ConvectionBC,
     CurrentBC,
+    DualValleyEffectiveDOS,
     HeatFluxBC,
     HeatFromElectricSource,
     HeatSource,
     InsulatingBC,
+    IsotropicEffectiveDOS,
+    MultiValleyEffectiveDOS,
     RadiativeRecombination,
     ShockleyReedHallRecombination,
     SlotboomBandGapNarrowing,
@@ -441,6 +449,10 @@ def set_logging_level(level: str) -> None:
     "CoaxialLumpedResistor",
     "ConstantDoping",
     "ConstantMobilityModel",
+    "ConstantEffectiveDOS",
+    "IsotropicEffectiveDOS",
+    "MultiValleyEffectiveDOS",
+    "DualValleyEffectiveDOS",
     "ContinuousWave",
     "ContinuousWaveTimeModulation",
     "ContourPathAveraging",
@@ -651,6 +663,7 @@ def set_logging_level(level: str) -> None:
     "Staircasing",
     "SteadyCapacitanceData",
     "SteadyCapacitanceMonitor",
+    "SteadyChargeDCAnalysis",
     "SteadyEnergyBandData",
     "SteadyEnergyBandMonitor",
     "SteadyFreeCarrierData",
@@ -696,4 +709,7 @@ def set_logging_level(level: str) -> None:
     "set_logging_console",
     "set_logging_file",
     "wavelengths",
+    "ConstantEnergyBandGap",
+    "QuadraticEnergyBandGap",
+    "VarshniEnergyBandGap",
 ]

tidy3d/components/material/tcad/charge.py

@@ -9,6 +9,8 @@
 from tidy3d.components.tcad.doping import DopingBoxType
 from tidy3d.components.tcad.types import (
     BandGapNarrowingModelType,
+    EffectiveDOSModelType,
+    EnergyBandGapModelType,
     MobilityModelType,
     RecombinationModelType,
 )
@@ -254,21 +256,21 @@ class SemiconductorMedium(AbstractChargeMedium):
 
     """
 
-    N_c: pd.PositiveFloat = pd.Field(
+    N_c: EffectiveDOSModelType = pd.Field(
         ...,
         title="Effective density of electron states",
         description=r"$N_c$ Effective density of states in the conduction band.",
         units="cm^(-3)",
     )
 
-    N_v: pd.PositiveFloat = pd.Field(
+    N_v: EffectiveDOSModelType = pd.Field(
         ...,
         title="Effective density of hole states",
         description=r"$N_v$ Effective density of states in the valence band.",
         units="cm^(-3)",
     )
 
-    E_g: pd.PositiveFloat = pd.Field(
+    E_g: EnergyBandGapModelType = pd.Field(
         ...,
         title="Band-gap energy",
         description="Band-gap energy",

tidy3d/components/spice/analysis/dc.py

@@ -49,19 +49,11 @@ class ChargeToleranceSpec(Tidy3dBaseModel):
     )
 
 
-class IsothermalSteadyChargeDCAnalysis(Tidy3dBaseModel):
+class SteadyChargeDCAnalysis(Tidy3dBaseModel):
     """
     Configures relevant steady-state DC simulation parameters for a charge simulation.
     """
 
-    temperature: pd.PositiveFloat = pd.Field(
-        300,
-        title="Temperature",
-        description="Lattice temperature. Assumed constant throughout the device. "
-        "Carriers are assumed to be at thermodynamic equilibrium with the lattice.",
-        units=KELVIN,
-    )
-
     tolerance_settings: ChargeToleranceSpec = pd.Field(
         default=ChargeToleranceSpec(), title="Tolerance settings"
     )
@@ -83,3 +75,17 @@ class IsothermalSteadyChargeDCAnalysis(Tidy3dBaseModel):
         "where very high doping may lead the pseudo-Fermi energy level to approach "
         "either the conduction or valence energy bands.",
     )
+
+
+class IsothermalSteadyChargeDCAnalysis(SteadyChargeDCAnalysis):
+    """
+    Configures relevant steady-state DC simulation parameters for a charge simulation.
+    """
+
+    temperature: pd.PositiveFloat = pd.Field(
+        300,
+        title="Temperature",
+        description="Lattice temperature. Assumed constant throughout the device. "
+        "Carriers are assumed to be at thermodynamic equilibrium with the lattice.",
+        units=KELVIN,
+    )

tidy3d/components/spice/types.py

@@ -2,6 +2,9 @@
 
 from typing import Union
 
-from tidy3d.components.spice.analysis.dc import IsothermalSteadyChargeDCAnalysis
+from tidy3d.components.spice.analysis.dc import (
+    IsothermalSteadyChargeDCAnalysis,
+    SteadyChargeDCAnalysis,
+)
 
-ElectricalAnalysisType = Union[IsothermalSteadyChargeDCAnalysis]
+ElectricalAnalysisType = Union[SteadyChargeDCAnalysis, IsothermalSteadyChargeDCAnalysis]