Introduction State vectors Stern Gerlach experiment S N B zÙ o v e n c o l l i m a t o r t o d e t e c t o r In the Stern Gerlach experiment • silver atoms are heated in an oven, from which they escape through a narrow slit, • the atoms pass through a collimator and enter an inhomogenous magnetic field, we assume the field to be uniform in the xy-plane and to vary in the z-direction, • a detector measures the intensity of the electrons emerging from the magnetic field as a function of z. We know that • 46 of the 47 electrons of a silver atom form a spherically symmetric shell and the angular momentum of the electron outside the shell is zero, so the magnetic moment due to the orbital motion of the electrons is zero, • the magnetic moment of an electron is cS, where S is the spin of an electron, • the spins of electrons cancel pairwise, • thus the magnetic moment µ of an silver atom is almost solely due to the spin of a single electron, i.e. µ = cS, • the
