Dynamics of driven interfaces with a conservation law

The dynamics of a growing interface with conservation of total volume under the interface is investigated using both dynamic renormalization-group and computer simulation. The conservation law leads to a new universality class from that discussed by Kardar, Parisi, and Zhang [Phys. Rev. Lett. 56, 889 (1986)]. The growth exponents are calculated and compared with those from the simulation of a conserved restricted solid-on-solid model. Excellent agreement between theory and simulation is found.