Quantum photonics with spins in semiconductor nanostructures

Electron and hole spins can be confined in a variety of semiconductor nanostructures, including quantum dots, nanowires or monolayers. These spins can have long coherence times and can be addressed using ultra-fast optical techniques. This makes them very suitable for quantum photonics, which promises advances in fields such as quantum communication, sensing and computation. We focus on electron spins confined in self-assembled InAs quantum dots, which are initialized, manipulated and read out using optical techniques. In recent years it has been established that the electron spin’s coherence time is limited by fluctuations in the nuclear spin bath, which couple to the electron spin via the hyperfine interaction. Hole spins are less affected, but they suffer from electric fluctuations due to the hole’s larger spin-orbit interaction. Although techniques are being developed to reduce these sources of noise in the electric and magnetic environment, it is probably not feasible to suppress them completely. Fortunately, we can engineer a system of two tunnel-coupled quantum dots to feature “atomic-clock states”, which are robust against both electric and magnetic fluctuations simultaneously.

Speaker: Dr Jeroen Elzerman (UCL) 

Time: 16:30-17:30

Location: David Sizer Lecture Theatre

Refreshments will be served after the event.