An original gadolinium-hybridized plasmonic gold nanocomposite is fabricated to provide an insightful and attractive strategy to overcome both the physiological and pathological barriers of tumor, and increase the transportation and permeability of imaging agents and drugs in tumor interior for achieving high-sensitive multimodal imaging and simultaneously improving the therapeutic efficacy of cancer.

The electrostatic tunability of graphene is vital in the field of active plasmons and would be beneficial in tunable infrared and terahertz optical element applications. The key to realizing broad tunability is achieving high carrier densities in graphene. Here we use an ion-gel, currently one of the most efficient dielectrics with ultra-high capacitance, to realize broadly tunable graphene plasmons (∼1270 cm(-1)) with low voltage modulation (∼4 V shifted from the Dirac point). We further explore the coupling between graphene plasmons and the molecular vibration modes of the ion-gel, since strong plasmon-phonon coupling can split the plasmon resonance peak into multi-peaks and reduce their tunability. Our experiments demonstrate weak plasmon-phonon coupling in the graphene/ion-gel system, which has limited effects on plasmon properties. These properties make ion-gels an effective dielectric for broadly tunable graphene plasmonic devices, such as new optical modulators, filters and wavelength multiplexers.

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A high-quality field emission electron source made of a highly ordered array of carbon nanotubes (CNTs) coated with a thin film of hexagonal boron nitride (h-BN) is fabricated using a simple and scalable method. This method offers the benefit of reproducibility, as well as the simplicity, safety, and low cost inherent in using B(2)O(3) as the boron precursor. Results measured using h-BN-coated CNT arrays are compared with uncoated control arrays. The optimal thickness of the h-BN film is found to be 3 nm. As a result of the incorporation of h-BN, the turn-on field is found to decrease from 4.11 to 1.36 V μm(-1), which can be explained by the significantly lower emission barrier that is achieved due to the negative electron affinity of h-BN. Meanwhile, the total emission current is observed to increase from 1.6 to 3.7 mA, due to a mechanism that limits the self-current of any individual emitting tip. This phenomenon also leads to improved emission stability and uniformity. In addition, the lifetime of the arrays is improved as well. The h-BN-coated CNT array-based field emitters proposed in this work may open new paths for the development of future high-performance vacuum electronic devices.