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arXiv · 1712.02077

Amplified and tunable transverse and longitudinal spin-photon coupling in hybrid circuit-QED

Neill Lambert·Mauro Cirio·Matthieu Delbecq·Giles Allison·Marian Marx·Seigo Tarucha·Franco Nori
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Abstract

We describe a method to tune, in-situ, between transverse and longitudinal light-matter coupling in a hybrid circuit-QED device composed of an electron spin degree of freedom coupled to a microwave transmission line cavity. Our approach relies on periodic modulation of the coupling itself, such that in a certain frame the interaction is both amplified and either transverse, or, by modulating at two frequencies, longitudinal. The former realizes an effective simulation of certain aspects of the ultra-strong coupling regime, while the latter allows one to implement a longitudinal readout scheme even when the intrinsic Hamiltonian is transverse, and the individual spin or cavity frequencies cannot be changed. We analyze the fidelity of using such a scheme to measure the state of the electron spin degree of freedom, and argue that the longitudinal readout scheme can operate in regimes where the traditional dispersive approach fails.

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Neill Lambert, Mauro Cirio, Matthieu Delbecq, Giles Allison, Marian Marx, Seigo Tarucha, Franco Nori. 2017-12-06. Amplified and tunable transverse and longitudinal spin-photon coupling in hybrid circuit-QED. https://doi.org/10.1103/physrevb.97.125429

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