The first operation of an electrically pumped 1.3μm InAs/GaAs quantum-dot laser was previously reported epitaxially grown on Si （100） substrate. Here the direct epitaxial growth condition of 1.3μm InAs/OaAs quantu...The first operation of an electrically pumped 1.3μm InAs/GaAs quantum-dot laser was previously reported epitaxially grown on Si （100） substrate. Here the direct epitaxial growth condition of 1.3μm InAs/OaAs quantum on a Si substrate is further investigated using atomic force microscopy, etch pit density and temperature-dependent photoluminescence （PL） measurements. The PL for Si-based InAs/GaAs quantum dots appears to be very sensitive to the initial OaAs nucleation temperature and thickness with strongest room-temperature emission at 40000 （17Onto nucleation layer thickness）, due to the lower density of defects generated under this growth condition, and stronger carrier confinement within the quantum dots.展开更多
This research proposes a simple and practical method to make low-stray-light gratings, where the substrate shifts about a 1 mm distance in the direction parallel or perpendicular to the exposure interference fringes. ...This research proposes a simple and practical method to make low-stray-light gratings, where the substrate shifts about a 1 mm distance in the direction parallel or perpendicular to the exposure interference fringes. When the substrate shifts, a reference grating next to the substrate is used to adjust in real time the phase of the exposure interference fringes relative to the substrate. Shifting eliminates the exposure defects and therefore decreases the stray light of gratings. Several gratings are successfully made by using this method, which have straighter grooves,smoother surfaces, and lower stray light than gratings made in conventional interference lithography.展开更多
CONSPECTUS:Catalytic biomaterials,an emerging frontier in biomaterials research,offer tremendous potential to circumvent the limitations of traditional treatment approaches,such as low specificity and adverse effects....CONSPECTUS:Catalytic biomaterials,an emerging frontier in biomaterials research,offer tremendous potential to circumvent the limitations of traditional treatment approaches,such as low specificity and adverse effects.By harnessing the intrinsic physicochemical properties of materials,catalytic biomaterials,especially nanoscale catalytic biomaterials(termed catalytic nanomedicine),can directly engage with a range of biogenic substrates to initiate various chemical or biochemical reactions in vivo.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11434010,11574356 and 11504415the Funds from the Royal Society,the Defense Science Technology Laboratory and UK Engineering and Physics Research Council
文摘The first operation of an electrically pumped 1.3μm InAs/GaAs quantum-dot laser was previously reported epitaxially grown on Si （100） substrate. Here the direct epitaxial growth condition of 1.3μm InAs/OaAs quantum on a Si substrate is further investigated using atomic force microscopy, etch pit density and temperature-dependent photoluminescence （PL） measurements. The PL for Si-based InAs/GaAs quantum dots appears to be very sensitive to the initial OaAs nucleation temperature and thickness with strongest room-temperature emission at 40000 （17Onto nucleation layer thickness）, due to the lower density of defects generated under this growth condition, and stronger carrier confinement within the quantum dots.
基金supported by the National Natural Science Foundation of China under Grant No.51427805
文摘This research proposes a simple and practical method to make low-stray-light gratings, where the substrate shifts about a 1 mm distance in the direction parallel or perpendicular to the exposure interference fringes. When the substrate shifts, a reference grating next to the substrate is used to adjust in real time the phase of the exposure interference fringes relative to the substrate. Shifting eliminates the exposure defects and therefore decreases the stray light of gratings. Several gratings are successfully made by using this method, which have straighter grooves,smoother surfaces, and lower stray light than gratings made in conventional interference lithography.
文摘CONSPECTUS:Catalytic biomaterials,an emerging frontier in biomaterials research,offer tremendous potential to circumvent the limitations of traditional treatment approaches,such as low specificity and adverse effects.By harnessing the intrinsic physicochemical properties of materials,catalytic biomaterials,especially nanoscale catalytic biomaterials(termed catalytic nanomedicine),can directly engage with a range of biogenic substrates to initiate various chemical or biochemical reactions in vivo.
