This is a pair of desktop models. One of the Bloch sphere (a Qubit) https://en.wikipedia.org/wiki/Bloch_sphere
and also the Poincare sphere (polarized light) https://en.wikipedia.org/wiki/Polarization_(waves)#Poincar%C3%A9_sphere
I got sick of trying to imagine rotations in my head, and I really wanted something tangible to hold, so I made these.
Construction is from lasercut acrylic or plywood, glued together. To house everything I used a 120mm acrylic sphere. These are typically sold on ebay as "bath bomb" moulds.
Further details here: