spheres.stars.star_utils.spin_coherent

spheres.stars.star_utils.spin_coherent(j, coord, from_cartesian=True, from_spherical=False, from_complex=False, from_spinor=False)[source]

Returns the spin-j coherent state which is defined by having all its Majorana stars located at a single point on the sphere. This point can be given in terms of cartesian, spherical, extended complex, and spinorial coordinates.

Parameters

  • j (int) – j value which indexes the \(SU(2)\) representation.

  • coord (nd.array or qt.Qobj or complex/inf) – Coordinates specifying the direction of the spin coherent state.

  • from_cartesian (bool, optional) – Whether the provided coordinates are cartesian (default).

  • from_spherical (bool, optional) – Whether the provided coordinates are spherical.

  • from_complex (bool, optional) – Whether the provided coordinates are extended complex.

  • from_spinor (bool, optional) – Whether the provided coordinates are spinorial.

Returns

spin_coherent – Spin-j coherent state in the specified direction.

Return type

qt.Qobj