Progress of microscopic thermoelectric effects studied by micro- and nano-thermometric techniques

Heat dissipation is one of the most serious problems in modern integrated electronics with continuously decreasing devices size. Large portion consumed power inevitably dissipated form waste heat which not only restricts device energy-efficiency performance itself, but also leads to severe environment and energy crisis. Thermoelectric Seebeck effect a green energy-recycling method, while thermoelectric Peltier can be employed for management by actively cooling overheated devices, where passive conduction sufficiently enough. However, technological applications thermoelectricity are limited so far their very low conversion efficiencies lack deep understanding microscopic levels. Probing managing therefore fundamentally important particularly nanoscale. In this short review, we will first briefly introduce techniques studying nanoscale thermoelectricity, focusing mainly on scanning thermal microscopy (SThM). SThM powerful tool mapping lattice nanometer spatial resolution hence detecting transport processes. Then review recent experiments utilizing these investigate various nanomaterial systems including both (two-material) heterojunctions (single-material) homojunctions tailored coefficients, spin effects magnetic materials. Next, provide perspective promising our recently developed Scanning Noise Microscope (SNoiM) directly probing non-equilibrium transporting hot charges (instead heat) devices. SNoiM together expected able more complete comprehensive mechanisms thermoelectrics. Finally, make conclusion outlook future development studies