Amplitude expansion for the Grinfeld instability due to uniaxial stress at a solid surface

The physical origin of the Grinfeld melting instability at the surface of a uniaxially strained solid is briefly discussed. The calculation of the energy is pushed to the fourth order in interface displacement h. It is thus shown that the instability is usually subcritical (first order). Moreover, harmonic generation leads to grooves on the back side (that of the solid).