Quantum Hall plasmonics for quantum computation

Quantum Hall edge plasmons have some characteristic features that can be useful to measure and control solid state qubits. For example, it was recently demonstrated that their chirality can be exploited to implement passive non-reciprocal devices, such as gyrators and circulators, that exhibit good scalability performance. The improved scalability is related to the high ratio between the transverse voltage and the current, which is typical of the quantum Hall effect. Since the velocity of the edge excitations is inversely proportional to this ratio, shorter wavelengths have higher frequencies than in usual microwave devices. This high off-diagonal resistance can also be exploited to implement nearly dissipationless transmission lines and resonators with high characteristic impedance. This talk will focus on the latest theoretical developments on this topic. Different ways to implement these plasmonic transmission lines, e.g. with distributed or lumped elements, will be discussed and a quantitative analysis of different coupling schemes to semiconducting qubits will be presented.