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Novel charge and energy transport phenomena arise in molecular-scale junctions.In this lecture,I will first describe the fundamentals of charge and transport in molecular scale junctions and introduce experimental techniques developed in our lab and other research groups aimed at studying these phenomena.Specifically,I will describe scanning probe techniques that have been developed to enable the study of electrical conductance and thermopower of molecular junctions.Further,I will describe other techniques that have been developed to enable active control of transport in molecular junctions.Finally,I explain in detail recent efforts in our lab to understand: a)the relationship between the electronic structure and heat dissipation characteristics of atomic and molecular junctions,and b) the relationship between the thermal conductance and the structure of atomic-scale junctions.In order to accomplish the first goal,we have nanofabricated novel scanning probes—with integrated thermocouples—that enable direct quantification of heat dissipation in atomic-scale junctions.We will describe,in detail,how these probes were employed to elucidate asymmetric heat dissipation characteristics of atomic-scale junctions.In order to accomplish the second goal—probing heat transport at the atomic-scale—it is necessary to accurately measure very small heat currents(10-100 picowatts).To overcome this challenging experimental obstacle,we have fabricated novel scanning probes that can resolve heat currents with a resolution better than 10 pW.We will briefly discuss the design and capabilities of these probes.