Tuning heat transport in graphene by tension

The speed of sound and flexural phonons in two-dimensional materials depends strongly on the tension in these ultraflexible membranes. Here, the authors experimentally demonstrate that freestanding graphene membranes cool down 33% faster when increasing tension by electrostatic gating. They attribute this effect mainly to improved acoustic impedance match of flexural phonons at the boundaries of the membrane and thus provide a route towards electronic devices and circuits for high-speed control of nanoscale heat transport.