State Transfer Between a Mechanical Oscillator and Microwave Fields in the Quantum Regime

Recently, macroscopic mechanical oscillators have been coaxed into a regime of quantum behavior, by direct refrigeration [1] or a combination of refrigeration and laser-like cooling [2, 3]. This exciting result has encouraged notions that mechanical oscillators may perform useful functions in the processing of quantum information with superconducting circuits [1, 4-7], either by serving as a quantum memory for the ephemeral state of a microwave field or by providing a quantum interface between otherwise incompatible systems [8, 9]. As yet, the transfer of an itinerant state or propagating mode of a microwave field to and from a mechanical oscillator has not been demonstrated owing to the inability to agilely turn on and off the interaction between microwave electricity and mechanical motion. Here we demonstrate that the state of an itinerant microwave field can be coherently transferred into, stored in, and retrieved from a mechanical oscillator with amplitudes at the single quanta level. Crucially, the time to capture and to retrieve the microwave state is shorter than the quantum state lifetime of the mechanical oscillator. In this quantum regime, the mechanical oscillator can both store and transduce quantum information

Develop self adhesive to stick on moist and icy substrates

Normal acrylic-based adhesives that stick to dry surfaces, do not stick to surfaces with a water film. The water decreases the Hamaker constant, which indicates the strength of the Van der Waals forces, by a factor 10. The time needed to squeeze out the water by applying pressure to a label on top of a wet surface, is too long for normal applications. Approaches to remove, use and penetrate the moisture layer are proposed. This work focuses on proposals for water removal and this case is analyzed theoretically and tested experimentally. Pores are needed to transport the water away from the gap between the substrate and the adhesive layer. We show experimentally that adhesives with pores (50 µm diameter, 1 mm spacing) have a larger pull-off force on wet surfaces after applying pressure than adhesives without pores. Theoretical calculations for a 20µm thick adhesive layer of 645 mm2 surface area with 800 holes of 10µm diameter, show that the maximum volume of water retainable in the capillaries is 1.5 .10 -12 m3. This value is 500 times less than the volume of water squeezed out when the layer is reduced to 1µm. Therefore pores need to be made through both the adhesive and film layer where the water can evaporate or an absorbance layer is needed. Alternative strategies proposed to improve adhesion performance on moist icy surfaces include addition of polysaccharides, (poly)electrolytes, nanofibres, functionalized superhydrophobic and superhydrophilic patterns of the adhesive laye