Path Towards Exciton Condensation at High Temperatures

Excitons are composite bosons made of bound electron-hole pairs in semiconductors. With a much smaller mass than atoms, they are expected to Bose-condense at much higher temperature scales. This is especially the case for the tightly bound excitons in two-dimensional (2D) semiconductors; theoretical studies have predicted the possibility of realizing exciton superfluidity near room temperature. In this talk, I will discuss our recent efforts in creating a high-density equilibrium exciton fluid in atomic double layers made of 2D semiconductors. I will present results from both thermodynamics and transport measurements that help establish the emergence of a high-temperature excitonic insulating state. If time permits, I will also discuss the physics of a doped excitonic insulator that can support a Bose-Fermi mixture and an equilibrium trion fluid.

Speaker: Kin Fai Mak, Stanford university