Noncritical behavior in Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 relaxor ferroelectric crystals detected by acoustic emission method

[011]-oriented unpoled relaxor ferroelectric Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 crystals are studied by means of acoustic emission and dielectric methods in dependence on both temperature and dc bias electric field. The rhombohedral-cubic ferroelectric phase transition and the dielectric maximum as well as the intermediate temperature are successfully detected. Both rhombohedral-cubic ferroelectric phase transition and the dielectric maximum are studied in dependence on dc bias electric field, too. No the critical end point, but the tricritical one is detected. Existence of the supercritical behavior is discussed in these crystals.