Make a logo, possibly using QuantumToolbox.jl

[albertomercurio]

Make a logo for the package, possibly using the QuantumToolbox.jl package.

What I have in mind is for example creating the Wigner function a triangular cat state

$$ \ket{\psi} = \ket{\alpha} + \ket{e^{i \frac{2}{3} \pi} \alpha} + \ket{e^{i \frac{4}{3} \pi} \alpha} $$

and possibly mapping the colors following the Julia logo.

Then, we can add a documentation page demonstrating how this logo was made, showing step by step the code.

[ytdHuang]

Good idea !

[ytdHuang]

@albertomercurio

I suggest the background color of the logo to be transparent.

Then, we can prepare two different logo (for light- and dark-theme website), and put it in the folder docs/src/assets/.

The file name must be:

• logo.png: logo for light-theme website, maybe with the black color characters (QuantumToolbox) in the logo
• logo-dark.png: logo for dark-theme website, maybe with the white color characters (QuantumToolbox) in the logo: QuantumToolbox)

In this case, the Documenter.jl will automatically detect the logo files if it is located in docs/src/assets/.

Also, we can insert the logo to README.md by adding the following lines in the beginning:

![Fancy logo](./docs/src/assets/logo-dark.png#gh-dark-mode-only)
![Fancy logo](./docs/src/assets/logo.png#gh-light-mode-only)