  We theoretically study the diamagnetic levitation and the thermal-driven
motion of graphite. Using the quantum-mechanically derived magnetic
susceptibility, we compute the equilibrium position of levitating graphite over
a periodic arrangement of magnets, and investigate the dependence of the
levitation height on the susceptibility and the geometry. We find that the
levitation height is maximized at a certain period of the magnets, and the
maximum height is then linearly proportional to the susceptibility of the
levitating object. We compare the ordinary AB-stacked graphite and a randomly
stacked graphite, and show that the latter exhibits a large levitation length
particularly in low temperatures, because of its diamagnetism inversely
proportional to the temperature. Finally, we demonstrate that the temperature
gradient moves the levitating object towards the high temperature side, and
estimate the generated force as a function of susceptibility.
