Physical Realization of a Lifshitz Point in Liquid Crystals

A theoretically based proposal of a concrete physical realization of a Lifshitz point is given for the first time. This point should occur on the H-T diagram of a chiral liquid crystal exhibiting a second-order transition between the smectic phases A and helicoidal C (H is a magnetic field parallel to the smectic layers). The phase diagram near this point is shown to be similar to the one obtained in the case of uniaxial magnetization.