A North Carolina State University researcher has developed a more efficient, less expensive way of cooling electronic devices -- particularly devices that generate a lot of heat, such as lasers and power devices. The technique uses a “heat spreader” made of a copper-graphene composite, which is attached to the electronic device using an indium-graphene interface film “Both the copper-graphene and indium-graphene have higher thermal conductivity, allowing the device to cool efficiently,” says Dr. Jag Kasichainula, an associate professor of materials science and engineering at NC State and author of a paper on the research. Thermal conductivity is the rate at which a material conducts heat.