Quest of thermoelectricity in topological insulators: A density functional theory study

In this Paper, we have studied the structural, electronic and thermoelectric properties of LuAuPb and YAuPb compound respectively with frame work of density functional theory and Boltzmann equations. Our calculations show that both these compounds are gapless materials. Under strain, electronic and thermoelectric properties of these compounds are also studied. Under 5% strain, the maximum energy band gap opens up in LuAuPb compound. The thermoelectric properties of these compounds are studied between temperature range of 100-1000 K. Thermoelectric properties of these compound as a function of temperature are studied for the first time in this work. Seebeck measurements indicate that both these compounds are n-type in nature. The calculated electrical conductivity of these compounds under 5% strain increases with increase in temperature. The trends of electrical conductivity confirms that these compounds are semiconductor in nature. As temperature increases the electronic thermal conductivity of these compounds also increase. The maximum figure of merit is achieved for LuAuPb compound which is equal to 0.4.