Dynamics of superatom quantum dots: single photon emission

Most current platforms for quantum information technology rely on low temperature, either produced by cryogenic cooling as in the case of quantum dots or laser cooling as in the case of atom and ion traps. In all cases this cooling carries a considerable overhead which reduces the potential for scaling. In this proposal we explore a novel quantum technology based on highly excited room temperature atoms. The key quantum ingredient is the strong interactions between highly excited Rydberg states. The term Rydberg is used to describe an atom in a state where the average position of the outer electron is very far from the nucleus, of order 10,000 farther away than for a ground state atom. Rydberg atoms are extremely sensitive to electric fields and extremely sensitive to each other. If a laser is applied to excite atoms to a Rydberg state the energy level shifts induced by strong atomic interactions inhibit multiple excitations by a process known as blockade. This blockade mechanism results in a highly entangled quantum state known as a superatom. In the superatom state the single excitation is distributed equally among all the constituent atoms. As the superatom can support only one electronic excitation, it may be considered as the atomic analogue of a semiconductor quantum dot. In contrast to most other quantum information technologies, superatom quantum dots in thermal ensembles require neither cryogenic nor laser cooling, and consequently offer a robust and practical platform for quantum information science.The goal of the project is to develop a high bandwidth probe to detect the dynamics of superatoms in thermal atomic ensembles, and investigate single photon emission from a superatom. The project will lay the foundations for scalable, room temperature, quantum computing.