QDev Seminar: J.M. Taylor – University of Copenhagen

QDev Seminar: J.M. Taylor

Joint Center for Quantum Information and Computer Science
and Joint Quantum Institute

Coupling spins and photons in the microwave domain

While electrons couple directly to photons via their charge, spin-based coupling is suppressed by the weakness of perturbative quantum electrodynamics. Here we consider several complementary approaches for coupling individual charges and spins in semiconductor quantum dots to each other using photons as an intermediary. An emerging paradigm — microwave circuit QED-based resonators in the strong coupling regime with a electric-dipole allowed spin qubit — provides a reasonable starting point. However, extensions into the mesoscopic domain, in which the photon becomes synonymous with particle-hole excitations of a Fermi sea, show that this paradigm can extend into much shorter range dynamics than previously considered. Furthermore, I will show that in some cases the strong coupling of the charge sector of these systems to phonons enables new photonics applications, including the creation of single photon sources, masers, and even a controlled chemical potential for microwave photons.