The first paper emerging from our collaboration with Carlos was just published in PRL (open access). Zeyu and Oliver showed both analytically and numerically that placing two qubits in a suitably engineered waveguide results in perfect state transfer between the qubits. Whereas a conventional waveguide results in no more than 54% transfer efficiency (see top panel in the image), our new design reaches close to 100% by inverting the pulse shape (see bottom panel).
