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Summary and introduction


Software documentation



Software documentation


Software documentation

nextnano GmbH


The following page (in construction) describes the simulation of devices with open boundary conditions such as RTDs with the nextnano.NEGF software.

Note that in the current version (2020-06-18), only single band calculations are supported for such open boundary conditions.

Simulation of devices with open boundary conditions

In order to simulate a system with open boundary conditions (instead of the default field-periodic boundary condition), contacts have to be defined by adding a <Contacts> section in the input file:

   <DensityLeft unit="cm^-3">1e18</DensityLeft>
   <DensityRight unit="cm^-3">1e18</DensityRight>

   <Broadening unit="meV">10.0</Broadening>

In this section, the carrier densities in the left and right contact have to been defined using the <DensityLeft> and <DensityRight> commands, as shown above. The unit is cm$^{-3}$.

The material of the left and right contacts needs to be defined by te command <MaterialLeft> and <MaterialRight>. The string value has to be an alias defined in the <Materials> section of the input file.

A broadening energy can be defined by the command <Broadening>. Indeed, scattering is not accounted in the contact, so that this commands allows a phenomenological broadening of the density of states in the contact.

The command <Ballistic> can be used to calculate ballistic transport between the contacts (i.e. no scattering process considered) if its value is set to yes.

qcl/simulation_of_resonant_tunneling_diodes_rtds.txt · Last modified: 2020/06/19 14:22 by thomas.grange