%0 Journal Article
%T Circuit QED with a graphene double quantum dot and a reflection-line resonator
%A Guang-Wei Deng
%A Da Wei
%A J. R. Johansson
%A Miao-Lei Zhang
%A Shu-Xiao Li
%A Hai-Ou Li
%A Gang Cao
%A Ming Xiao
%A Tao Tu
%A Guang-Can Guo
%A Hong-Wen Jiang
%A Franco Nori
%A Guo-Ping Guo
%J Physics
%D 2013
%I arXiv
%X Graphene has attracted considerable attention in recent years due to its unique physical properties and potential applications. Graphene quantum dots have been proposed as quantum bits, and their excited-state relaxation rates have been studied experimentally. However, their dephasing rates remain unexplored. In addition, it is still not clear how to implement long-range interaction among qubits for future scalable graphene quantum computing architectures. Here we report a circuit quantum electrodynamics (cQED) experiment using a graphene double quantum dot (DQD) charge qubit and a superconducting reflection-line resonator (RLR). The demonstration of this capacitive coupling between a graphene qubit and a resonator provides a possible approach for mediating interactions between spatially-separated graphene qubits. Furthermore, taking advantage of sensitive microwave readout measurements using the resonator, we measure the charge-state dephasing rates in our hybrid graphene nanostructure, which is found to be of the order of GHz. A spectral analysis method is also developed to simultaneously extract: the DQD-resonator coupling strength, the tunneling rate between the DQD charge states, and the charge-state dephasing rate. Our results show that this graphene cQED architecture can be a compelling platform for both graphene physics research and potential applications.
%U http://arxiv.org/abs/1310.6118v1