By Peter Weiss
Thermoelectric coolers were expected to render ordinary mechanical refrigerators obsolete, but these semiconductor-based gadgets remain costly bit players in refrigeration. While the electric-powered devices today chill such items as space-borne sensors, plug-in beverage coolers, and luxury car seats, scientific progress on the materials underlying the devices hasn’t moved much since the 1960s (SN: 9/6/97, p. 152: https://www.sciencenews.org/sn_arc97/9_6_97/bob1.htm).
The big chill in thermoelectric research may be thawing. Rama Venkatasubramanian and his colleagues at the Research Triangle Institute in Research Triangle Park, N.C., have started stacking semiconductor compounds in layers, each only a few atoms thick. Thermoelectric materials made this way are 2 times as efficient as the alloys used in current devices.