Normal-state Ettingshausen effect in La2-xSrxCuO4

A method for measurements of small (metallic) Ettingshausen coefficient (P) was developed. The influence of the dominating thermal effects, the Joule and Thomson heats, was eliminated by making use of the odd symmetry of the Ettingshausen temperature gradient with respect to reversal of the direction of the magnetic field and electrical current. The method was applied to La2-xSrxCuO4 (x = 0.03-0.35) high-T-c superconductor in the normal state. We have found that in the whale composition range the Ettingshausen coefficient is of the order of 10(-7) m(3) K J(-1) which is characteristic of typical metals. The coefficient changes sign from positive to negative near x approximate to 0.07. Weak variation of P is in contrast to the behaviour of other transport coefficients for La2-xSrxCuO4, such as the thermoelectric power or the Hall coefficient, which have been reported in the literature to change their values by more than two orders of magnitude with Sr doping.