Abstract
It is shown that when the two adjacent n and p arms of a thermocouple Peltier junction are shunted by a heavy silver film an 'infinite cascade' of differential cold and hot junctions is developed which effectively counteracts the flow of heat from the hot to the cold junction. When the thermal load on the cold junction is negligible, an improvement by a factor of between 1.5 and 3 has been obtained for the maximum temperature difference Delta Tmax over that attainable without the film. It is further shown that for this arrangement, in which there are conducting paths transverse to the lengths of the arms, the conventional formulae for the calculation of the maximum attainable temperature difference from the figure of merit of the thermoelectric substances requires modification. In addition to its thermodynamic interest, the method also appears to be of practical importance.