Abstract:
The search of material with improved thermoelectric properties continues to be
important and urgent problem. The first investigation of thermoelectric opportunities of low
dimensional structures began about decade ago in papers. Based on the simple model of
quantum well (QW) and constant relaxation time approximation the authors had demonstrated
theoretically and experimentally the possibility of considerable rise of
thermoelectric figure of merit (ZT) as the consequence of the effect of density of state increase
in such structures. Different approaches to this problem and different QW systems have been
considered . The general conclusion was that the ZT enhancement in quantum wells is
not as drastic as predicted by original simple model. At the same time an alternative way of
achieving higher ZT via the decrease of phonon thermal conductivity in low dimensional
structures has been proposed . More recently, attention turned to the structures of even
lower dimensionality such as quantum dot arrays.