Low-temperature pyroelectricity in thermodynamically nonequilibrium media

The temperature dependence of the pyroelectric coefficient gamma(sigma)(T) of pyroelectrics in thermodynamic equilibrium at T-->0 varies in accordance with Nernst's theorem by the law gamma(sigma)(T)proportional to T-n greate r than or equal to 3, which means a sharp drop in gamma(sigma)(T) for T < 1 .5 K and precludes the efficient use of pyroelectrics in technical applicat ions. It is shown experimentally that this fundamental limitation does not apply to thermodynamically nonequilibrium polar media, for which gamma(sigm a)(T)congruent to const for T < 1.5 K. (C) 2000 American Institute of Physi cs. [S1063-777X(00)01607-8].