This section describes how to install QTCAD and its dependencies.

1.1. Software requirements

QTCAD consists of three main Python libraries, and thus requires a properly working Python installation. The recommended Python distribution for QTCAD is Miniconda, which may be installed using the instructions on the official conda website. This will include both Python and conda, the preferred package management tool for QTCAD installation.

QTCAD also uses mesh files as input. These mesh files can be produced with Gmsh. Following the conda QTCAD installation instructions below ensures that Gmsh is properly installed in the QTCAD virtual environement. In any situation where this is not possible, Gmsh may be installed by following the instructions on the official Gmsh website or in the next section. The website also contains Gmsh tutorials. Video tutorials on how to use Gmsh can also easily be found on YouTube.

Similarly, 3D mesh and geometry files may be generated from 2D layouts using the Python API coded in devicegen. Again, the conda installation procedure explained below will install this package automatically. Manual installation of devicegen is explained in the devicegen installation page.

Remark that while QTCAD is a commercial proprietary software, all its dependencies specified above are available for free.

1.2. Hardware requirements

Precise hardware requirements are strongly dependent on the complexity of the problem being solved both in terms of size of the mesh and solvers being employed. Therefore, it is quite non-trivial to provide universal hardware requirements for QTCAD.

Instead, below, we give two examples of systems on which QTCAD simulations may be run successfully. The first system is a laptop which may be used to run basic simulations for meshes with up to approximately 200,000 nodes that define simple devices with one or two quantum dots. This system uses a processor that dates back from 2015 and should be interpreted as a minimal setup. The second system is a more advanced desktop workstation which we routinely use for complex simulations using meshes with up to approximately 2,000,000 nodes.

These configurations should be understood as typical system examples, and not as hard requirements. We have indeed successfully run QTCAD on a wide variety of systems (Windows, Mac, or Linux laptops, desktop workstations, cloud computing services, HPC clusters, etc.). Since computation times depend non-trivially on many factors such as the hardware being used, number of cores employed, solver, mesh dimension, convergence properties of the problem being studied, tolerance of the solvers, or basis-set dimension (in the case of the many-body solver), they are not given here. Instead, we encourage users to experiment with our tutorials and practical applications on their machine. Nevertheless, for simulations of typical few-electron single or double quantum-dot devices, a laptop or a desktop computer should suffice, and HPC clusters should not be necessary.

1.2.1. System 1 (laptop)


6th Gen Intel® Core™ i5-6300U @ 2.40GHz
(4 threads)


No discrete GPU, only integrated graphics
(GPU is used only for plotting in ParaView and mesh rendering in Gmsh)


8 GB


256 GB (SSD)


Windows 10

1.2.2. System 2 (desktop)


13th Gen Intel® Core™ i9-13900K @ 3.00 GHz
(32 threads)




128 GB


1 TB (SSD)


Linux (Ubuntu distribution)

1.2.3. Operating system

We officially support the following operating systems:

  • Windows

  • Linux

  • macOS

1.3. Downloading QTCAD

To download QTCAD, please visit the Nanoacademic client portal at


If you already have a Nanoacademic account, please log in using your password.

Otherwise, please create your account, and then log in.

If this was not already done, please proceed to fill in the required user profile information (name, email address, institution, phone number, etc.).

Once you have a valid profile, please click on the “Products” section and select QTCAD. You should then see the following page:

Getting a free trial version

Fig. 1.3.1 Getting a free QTCAD trial version

Click on “Start your free trial”.

You will then see the following page which will allow you to download your license.

Downloading a free trial license of QTCAD

Fig. 1.3.2 Downloading a free trial license of QTCAD

This will produce a file called license.lic which we discuss further in the License Activation page.

The next step is to click the “Download QTCAD” button. This will bring you to a page containing all available QTCAD versions. Please download the latest one at the top of the page.

1.5. Troubleshooting

If you encounter any issues during the installation process, please contact Nanoacademic for support. We will be happy to help you resolve any problems you may encounter. You may also first look at the Troubleshooting page to see if your issue is already addressed.