High-speed Pockels modulation and second-order nonlinearities are key components in optical systems, but CMOS-compatible platforms like silicon and silicon nitride lack these capabilities. Micro-transfer printing of thin-film lithium niobate offers a solution, but suspending large areas of thin films for long interaction lengths and high-Q resonators is challenging, resulting in a low transfer yield. We present a new source preparation method that enables reliable transfer printing of thin-film lithium niobate. We demonstrate its versatility by successfully applying it to gallium phosphide and silicon, and provide an estimate of the transfer yield by subsequently printing 25 lithium niobate films without fail.
Several established photonic platforms lack a nonzero Pockels and nonlinear coefficient. We developed a micro-transfer printing method to heterogeneously integrate thin-film lithium niobate and gallium phosphide with an experimentally shown transfer yield of near-unity.
During the COVID-19 outbreak in 2020, national governments took restrictive measures, such as a visitors ban, prohibition of group activities and quarantine, to protect nursing home residents against infections. As 'safety' prevailed, residents and close relatives had no choice but to accept the restrictions. Their perspectives are relevant because the policies had a major impact on them, but they were excluded from the policy decisions. In this study we looked into the moral attitudes of residents, close relatives and volunteers regarding the restrictions in retrospect, and what moral lessons they considered important.We conducted 30 semi-structured interviews with residents and close relatives and one focus group meeting with volunteers working in nursing homes. Data were transcribed verbatim and analyzed inductively. Subsequently, three Socratic dialogue meetings with residents, close relatives and volunteers were organized in which first analysis outcomes were discussed and dialogues were fostered into moral lessons for future pandemics. Outcomes were combined with moral theory following an empirical bioethics design.Critical perspectives regarding the COVID-19 restrictions grew in time. Various moral values were compromised and steered moral lessons for our future. The participants recognized three moral lessons as most important. First, constructing tailored (well-balanced) solutions in practice is desirable. Second, proper recognition is needed for the caring role that close relatives fulfill in practice. Third, a responsive power distribution should be in place that includes all stakeholder perspectives who are affected by the restrictions.Comparing the results with moral theory strengthens the plea for inclusion of all stakeholder groups in decision-making processes. To further concretize the moral lessons, tailored solutions can be realized with the use of moral case deliberations. Proper recognition includes actions addressing moral repair and including counter-stories in the debate. Responsive power distribution starts with providing clear and trustworthy information and including all perspectives.
We demonstrate a generic heterogeneous integration process flow for low-index photonic platforms, based on a two-step microtransfer printing approach. In this work, a silicon coupler is used for low-loss integration of III/V on silicon nitride.
