```
documentclass{article}
usepackage{amsmath}
usepackage{amssymb}
usepackage{amsfonts}
usepackage{tikz}
usetikzlibrary{positioning,arrows,calc,math,angles,quotes}
usepackage{blochsphere}
usepackage{braket}
begin{document}
%%%% Change these parameters to change the position of psi, or the size/rotation of the sphere
defrotationSphere{-110}
defradiusSphere{3cm}
defpsiLat{45}
defpsiLon{45}
begin{blochsphere}[radius=radiusSphere,opacity=0.1,rotation=rotationSphere]
%drawBallGrid[style={opacity=.3}]{360}{90}
% Draw the sphere...
%drawLongitudeCircle[]{rotationSphere} % draw the longitude that face us to delimit the sphere
%draw another circle
drawLongitudeCircle[style={lightgray}]{0}
% ... and the equatorial plane
drawLatitudeCircle[style={dashed}]{0}
% Define the different points on the bloch sphere
labelLatLon{ket0}{90}{0};
labelLatLon{ket1}{-90}{0};
labelLatLon{ketminus}{0}{180};
labelLatLon{ketplus}{00}{0};
labelLatLon{ketpluspi2}{0}{-90}; % Longitude seems to be defined in the "wrong" direction, hence the minus
labelLatLon{ketplus3pi2}{0}{-270};
labelLatLon{psi}{psiLat}{-psiLon};
% Draw and label the axis
draw[-latex] (0,0) -- (ket0) node[above,inner sep=.5mm] at (ket0) {footnotesize $z$};
draw[-latex] (0,0) -- (ketplus) node[below,inner sep=.5mm] at (ketplus) {footnotesize$x$};
draw[-latex] (0,0) -- (ketpluspi2) node[below,inner sep=.5mm] at (ketpluspi2) {footnotesize $y$};
% Draw |psi>
draw[-latex] (0,0) -- (psi) node[above]{footnotesize $ket{psi}$};
% Draw the angles
coordinate (origin) at (0,0);
{
% Will draw the angle/projection one the equatorial plane
setDrawingPlane{0}{0}
% Draw the projection: cos is used to compute the length of the projection
draw[current plane,dashed] (0,0) -- (-90+psiLon:{cos(psiLat)*radiusSphere}) coordinate (psiProjectedEquat) -- (psi);
% Draw the angle
pic[current plane, draw,fill=orange!50,fill opacity=.5, text opacity=1,"footnotesize $phi$", angle eccentricity=2.2]{angle=ketplus--origin--psiProjectedEquat};
}
{ setLongitudinalDrawingPlane{psiLon}
% Draw the angle
pic[current plane, draw,fill=orange!50,fill opacity=.5, text opacity=1,"footnotesize $theta$", angle eccentricity=1.5]{angle=psi--origin--ket0};
}
end{blochsphere}
end{document}
```