Reversing quantum trajectories with analog feedback

We demonstrate the active suppression of transmon qubit dephasing induced by dispersive measurement, using parametric amplification and analog feedback. By real-time processing of the homodyne record, the feedback controller reverts the stochastic quantum phase kick imparted by the measurement on the qubit. The feedback operation matches a model of quantum trajectories with measurement efficiency $\tilde{\eta} \approx 0.5$, consistent with the result obtained by postselection. We overcome the bandwidth limitations of the amplification chain by numerically optimizing the signal processing in the feedback loop and provide a theoretical model explaining the optimization result.Comment: 5 pages, 4 figures, and Supplementary Information (7 figures

Th1 Lymphokine Production Profiles of Nickel-Specific CD4+ T-Lymphocyte Clones from Nickel Contact Allergic and Non-Allergic Individuals

Panels of nickel-specific T-lymphocyte clones (TLC) were prepared from nickel-allergic and non-allergic donors. TLC from both panels showed similar levels of expression of TCRα/β, CD4, CD2, CD25, and CD29 and recognized nickel in association with class II HLA molecules with restriction determinants in HLA-DR, HLA-DP, and HLA-DQ. The lymphokine secretion was analyzed in TLC from both panels upon antigen-specific or non-specific stimulation and was compared with the secretion profiles of representants of pre-established human atopen-specific Th1 and Th2 cells. Nickel-specific TLC from both panels showed a lymphokine secretion pattern similar to the atopen-specific Th1 cells, although there was some variation from clone to clone. Most TLC secreted substantial amounts of IFN-γ, IL-2, TNF-α and GM-CSF, but little or no IL-4 and IL-5. The variation observed mainly concerned IL-2 secretion that could be low or absent in some of the TLC. The general secretion pattern did not change upon different modes of stimulation, including activation via CD3, CD2, or CD28. Because nickel-specific TLC from allergic and non-allergic individuals show a similar Th1 secretion pattern, the present results give no evidence that aberrant lymphokine secretion by CD4+ T cells determines the contact allergic state, as was found for atopic allergy in a previous study

Ferroelectric Thin-Film Capacitors and Piezoelectric Switches for Mobile Communication Applications

Thin-film ferroelectric capacitors have been integrated with resistors and active functions such as ESD protection into small, miniaturized modules, which enable a board space saving of up to 80%. With the optimum materials and processes, integrated capacitors with capacitance densities of up to 100 nF/mm2 for stacked capacitors combined with breakdown voltages of 90 V have been achieved. The integration of these high-density capacitors with extremely high breakdown voltage is a major accomplishment in the world of passive components and has not yet been reported for any other passive integration technology. Furthermore, thin-film tunable capacitors based on barium strontium titanate with high tuning range and high quality factor at 1 GHz have been demonstrated. Finally, piezoelectric thin films for piezoelectric switches with high switching speed have been realized

Geotechnical Engineering in Contracts for Civil Projects

Geo-Impuls is a Dutch nationwide programme with the aim to reduce geotechnical related failures in projects. During the last 5 years, a large number of teams have been working within three themes (techniques, communications and contracts) on a procedure for coping with the natural uncertainties of the Dutch subsoil. The large variation in the mainly soft subsoil in the Netherlands involves geotechnical risks. These risks need to be managed and controlled. The main focus of one of the themes of Geo-Impuls – theme ‘Geo-Engineering in Contracts’ – is how to deal with these risks during the different phases of a project and especially during the drawing up of the contract. Which party is able to manage geotechnical risks most effectively in which phase of the project? In addition, which party is responsible for which risks? Moreover, how can this responsibility be reduced, allocated and established? These questions are of current interest due to a shift in the methods of contracting. Nowadays the traditional form of contracting changes towards a more integrated form. Several parties are responsible for the project design or realization instead of only one party. Furthermore, the way of selecting the contractors is also changing. All this makes it difficult to make clear-cut agreements on how to deal with the geotechnical risks. It is no longer the responsibility of only the geotechnical consultant, but of the whole project team. Within ‘Geo-Engineering in Contracts’, research has been done on how to determine a method to deal with geotechnical risks in all phases of the project. Eventually, the following topics were identified and researched by different teams. 1. The determination of a risk controlled approach for the executing of soil investigation during all phases of the project. 2. The awareness of geotechnical risks and how to allocate these risks to the parties involved during all phases of the project. 3. The presentation of guidelines on how to successfully integrate geotechnical aspect in different contract forms. The article outlines the activities and results of these three topics of the Contracts-teams

Brackish water off-grid desalination systems for developing countries

The REvivED water project aims to contribute to overcoming the drinking water challenge through desalination technology. The goal is to produce safe and affordable drinking water with a significantly reduced energy consumption compared to the current state-of-the-art technology. The overall project comprises several systems and applications with twelve pilots in total, ranging from Electrodialysis (ED) small systems for brackish water desalination to larger scale hybrid (RED/ED-RO) systems for sea water desalination. Specific attention is devoted to develop energy efficient and robust brackish water desalination systems for application in developing countries. To reduce the energy consumption of the desalination process, several design parameters have been optimized, e.g., membranes and spacers characteristics, stack configurations, flow path length. To assure the system robustness, several concepts have been investigated, including pre-treatment options, capacitive electrodes, one pass flow as well as gravity driven flow. Intensive modelling and experimental validation are being carried out for the process and system design. The first brackish water desalination results demonstrate that up to a conductivity of ~4.000 \ub5s/cm the project energy consumption target of 0.4 kWh/m3 can be achieved

MI004 miniaturised, high performance ferroelectric and piezoelectric thin film devices

Thin film ferroelectric capacitors have been integrated with resistors and active functions such as ESD protection into small, miniaturized modules, which enable a board space saving of up to 80%. With the optimum materials and processes, integrated capacitors with capacitance densities of up to 100 nF/mm2 and breakdown voltages of exceeding 90 V have been achieved. The integration of these high density capacitors with extremely high breakdown voltage is a revolution in the world of passive components and has not yet been achieved in any other passive integration technology. Furthermore, thin film tunable capacitors based on barium strontium titanate with high tuning range and high quality factor at 1 GHz have been demonstrated. Finally, piezoelectric thin films for piezoelectric switches with high switching speed have been realized