Magnetization Dynamics in Synthetic Antiferromagnets with Perpendicular Magnetic Anisotropy

Understanding the rich physics of magnetization dynamics in perpendicular synthetic antiferromagnets (p-SAFs) is crucial for developing next-generation spintronic devices. In this work, we systematically investigate the magnetization dynamics in p-SAFs combining time-resolved magneto-optical Kerr effect (TR-MOKE) measurements with theoretical modeling. These model analyses, based on a Landau-Lifshitz-Gilbert approach incorporating exchange coupling, provide details about the magnetization dynamic characteristics including the amplitudes, directions, and phases of the precession of p-SAFs under varying magnetic fields. These model-predicted characteristics are in excellent quantitative agreement with TR-MOKE measurements on an asymmetric p-SAF. We further reveal the damping mechanisms of two procession modes co-existing in the p-SAF and successfully identify individual contributions from different sources, including Gilbert damping of each ferromagnetic layer, spin pumping, and inhomogeneous broadening. Such a comprehensive understanding of magnetization dynamics in p-SAFs, obtained by integrating high-fidelity TR-MOKE measurements and theoretical modeling, can guide the design of p-SAF-based architectures for spintronic applications.Comment: 24 pages, 5 figure

Étude des événements précipitants intenses en Méditerranée (approche par la modélisation climatique régionale)

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Single continuous wave laser induced photodynamic/plasmonic photothermal therapy using photosensitizer-functionalized gold nanostars

Chlorin e6 conjugated gold nanostars (GNS-PEG-Ce6) are used to perform simultaneous photodynamic/plasmonic photothermal therapy (PDT/PPTT) upon single laser irradiation. The early-phase PDT effect is coordinated with the late-phase PPTT effect to obtain synergistic anticancer efficiency. The prepared GNS-PEG-Ce6 shows excellent water dispersibility, good biocompatibility, enhanced cellular uptake and remarkable anticancer efficiency upon irradiation in vivo. Copyright ? 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Gold Nanoparticle-Based Activatable Probe for Sensing Ultra low Levels of Prostate-Specific Antigen

Intramural Research Program (IRP) of the National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH); NIH-NIBIB/NIST NRCIt Is still in high demand to develop extremely sensitive and accurate clinical tools for biomarkers of interest for early diagnosis and monitoring of diseases. In this report, we present a highly sensitive and compatible gold nanoparticle (AuNP)-based fluorescence-activatable probe for sensing ultralow levels of prostate-specific antigen (PSA) in patient serum samples. The limit of detection of the newly developed probe for PSA was pushed down to 0.032 pg/mL, which is more than 2 orders of magnitude lower than that of the conventional fluorescence probe. The ultrahigh sensitivity of this probe was attributed to the high loading efficiency of the dyes on AuNP surfaces and high fluorescence quenching-unquenching abilities of the dye-AuNP pairs. The efficiency and robustness of this probe were investigated In patient serum samples, demonstrating the great potential of this probe in real-world applications

Dual-factor triggered fluorogenic nanoprobe for ultrahigh contrast and subdiffraction fluorescence imaging

National Basic Research Program of China (973 program) [2013CB733802]; Henry M. Jackson Foundation; NIBIB/NIH, U.S.A.Ultrahigh contrast fluorescence molecular imaging has long been pursued over the past few decades from basic sciences to clinics. Although new classes of near-infrared (NIR) molecular probes are emerging, the requirement of fluorophores with high quantum yield, high signal to noise (S/N) ratio, and being activatable to microenvironment changes can hardly be fulfilled. In this study, a new NIR dye embedded fluorogenic nanoprobe (fg-nanoprobe) was developed for ultrahigh contrast in vitro and in vivo imaging with negligible background interference. The achieved S/N ratio was found to be attributed to the synergistic effects of the cellular compartmental triggered fluorogenicity and pH tunable fluorescence on/off character. In addition, this constructed fluorogenic nanoprobe could be coupled with image processing method for super-resolution subdiffraction imaging. The developed fg-nanoprobe integrated photophysical merits of the synthesized NIR fluorophore and advantages of engineered nanoparticle for enhanced fluorescence molecular imaging. This probe may open another avenue for ultrahigh contrast fluorescence molecular imaging in the future. Published by Elsevier Ltd

Gold nanoparticle-based activatable probe for sensing ultralow levels of prostate-specific antigen

It is still in high demand to develop extremely sensitive and accurate clinical tools for biomarkers of interest for early diagnosis and monitoring of diseases. In this report, we present a highly sensitive and compatible gold nanoparticle (AuNP)-based fluorescence-activatable probe for sensing ultralow levels of prostate-specific antigen (PSA) in patient serum samples. The limit of detection of the newly developed probe for PSA was pushed down to 0.032 pg/mL, which is more than 2 orders of magnitude lower than that of the conventional fluorescence probe. The ultrahigh sensitivity of this probe was attributed to the high loading efficiency of the dyes on AuNP surfaces and high fluorescence quenching-unquenching abilities of the dye-AuNP pairs. The efficiency and robustness of this probe were investigated in patient serum samples, demonstrating the great potential of this probe in real-world applications. ? 2013 American Chemical Society

Highly robust, recyclable displacement assay for mercuric ions in aqueous solutions and living cells

We designed a recyclable Hg2+ probe based on Rhodamine B isothiocyanate (RBITC)-poly(ethylene glycol) (PEG)-comodified gold nanoparticles (AuNPs) with excellent robustness, selectivity, and sensitivity. On the basis of a rational design, only Hg2+ can displace RBITC from the AuNP surfaces, resulting in a remarkable enhancement of RBITC fluorescence initially quenched by AuNPs. To maintain stability and monodispersity of AuNPs in real samples, thiol-terminated PEG was employed to bind with the remaining active sites of AuNPs. Besides, this displacement assay can be regenerated by resupplying free RBITC into the AuNPs solutions that were already used for detecting Hg2+. Importantly, the detection limit of this assay for Hg2+ (2.3 nM) was lower than the maximum limits guided by the United States Environmental Protection Agency as well as that permitted by the World Health Organization. The efficiency of this probe was demonstrated in monitoring Hg2+ in complex samples such as river water and living cells. 漏 2012 American Chemical Society