Effects of Spin Quantum Force in Magnetized Quantum Plasma

Starting from the governing equations for a quantum magnetoplasma including the electron spin -1/2 effects and quantum Bohm potential, we derive Korteweg-de Vries (KdV) equation of the system of quantum magnetohydrodynamics (QMHD). The amplitude and width of magnetosonic soliton with different parameters in the system are studied. It is found that the normalized Zeeman energy E plays a crucial role, for E >= 1 the amplitude r(m xi) and the width w(xi) of solitary wave all decrease as E increases. That is, the introduction of spin quantum force modifies the shape of solitary magnetosonic waves and makes them more narrower and shallower.