Circuit Quantum Electrodynamics Architecture for Gate-Defined Quantum   Dots in Silicon
  We demonstrate a hybrid device architecture where the charge states in a double quantum dot (DQD) formed in a Si/SiGe heterostructure are read out using an on-chip superconducting microwave cavity. A quality factor Q = 5,400 is achieved by selectively etching away regions of the quantum well and by reducing photon losses through low-pass filtering of the gate bias lines. Homodyne measurements of the cavity transmission reveal DQD charge stability diagrams and a charge-cavity coupling rate g_c/2pi = 23 MHz. These measurements indicate that electrons trapped in a Si DQD can be effectively coupled to microwave photons, potentially enabling coherent electron-photon interactions in silicon. 
X. Mi, J. V. Cady, D. M. Zajac, J. Stehlik, L. F. Edge, J. R. Petta
cond-mat.mes-hall quant-ph