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The control of light fields on subwavelength scales in nanophotonic structures has become ubiquitous, driven by both curiosity and a multitude of applications in fields ranging from biosensing to quantum optics. Mapping these fields in detail is crucial, as theoretical modelling is far from trivial and highly dependent on nanoscale geometry. Recent developments of nanoscale field mapping, particularly with near-field microscopy, have not only led to a vastly increased resolution, but have also resulted in increased functionality. The phase and amplitude of different vector components of both the electric and magnetic fields are now accessible, as is the ultrafast temporal or spectral evolution of propagating pulses in nanostructures. In this Review we assess the current state-of-the-art of subwavelength light mapping, highlighting the new science and nanostructures that have subsequently become accessible. [ABSTRACT FROM AUTHOR]

Control of light-matter interactions at the nanoscale has advanced fields such as quantum optics, photovoltaics and telecommunications. These advances are driven by an improved understanding of the nanoscale behaviour of light, enabled by direct observations of the local electric fields near photonic nanostructures. With the advent of metamaterials that respond to the magnetic component of light, schemes have been developed to measure the nanoscale magnetic field. However, these structures interact not only with the magnetic field, but also with the electric field of light. Here, we demonstrate the essential simultaneous detection of both electric and magnetic fields with subwavelength resolution. By explaining our measurements through reciprocal considerations, we create a route towards designing probes sensitive to specific desired combinations of electric and magnetic field components. Simultaneous access to nanoscale electric and magnetic fields will pave the way for new designs of optical nanostructures and metamaterials. [ABSTRACT FROM AUTHOR]

We use polarization-resolved near-field measurements, in conjunction with electromagnetic theory, to separate and quantify the electric and magnetic optical response of subwavelength holes in thick gold films. Using 1550 nm light, we determine the amplitudes of the electric and magnetic polarizabilities of holes with diameters ranging from 600 to 1000 nm. Additionally, we study the scattered field distributions that arise from the interactions of the holes with surface plasmon polaritons, and show that forward-backward scattering ratios as high as 2.5 : 1 are possible. Our study provides experimental access and theoretical understanding of the full electromagnetic polarizability that describes the optical response of metallic holes at telecom wavelengths, which is a prototypical structure in currently explored optical signal processing and sensing devices. [ABSTRACT FROM AUTHOR]

We map the complex electric fields associated with the scattering of surface plasmon polaritons by single subwavelength holes of different sizes in thick gold films. We identify and quantify the different modes associated with this event, including a radial surface wave with an angularly isotropic amplitude. This wave is shown to arise from the out-of-plane electric dipole induced in the hole, and we quantify the corresponding polarizability, which is in excellent agreement with electromagnetic theory. Time-resolved measurements reveal a time delay of 38 ± 18 fs between the surface plasmon polariton and the radial wave, which we attribute to the interaction with a broad hole resonance. [ABSTRACT FROM AUTHOR]

Stylized and voxelized phantoms have been used to estimate S-values for positron-emitting radionuclides. However, there is a lack of computational phantoms that include head and brain structures of importance for neuroimaging studies, such as brain PET-CT. The aim of this work was to construct a multi-resolution whole-body phantom for Monte Carlo simulations in MCNP code that includes a complete set of head and brain structures. The International Commission on Radiological Protection (ICRP-110) male reference phantom and the Zubal head phantom were used to construct the ICRP-HEAD phantom. This multi-resolution phantom was used to calculate self-absorbed fractions (SAFs) and S-values for seven positron-emitting radionuclides used in PET neuroimaging (C-11, O-15, F-18, Cu-64, I-124, Ga-68, and Y-86). S-values calculated in this work were compared with two head/brain phantoms previously published: the stylized MIRD-15 phantom and the tomographic VIP-Man phantom. The voxel resolution of the phantom resulted well suited for Monte Carlo simulations in MCNP6.2 code. For the same target and source structure, the highest auto absorbed S-values were produced by O-15 and Ga-68, while for different target and source structures, Y-86 produced the highest S-values. The lowest S-values were produced by Cu-64. Comparison of S-values with those calculated from the MIRD-15 phantom showed significant differences, while a better agreement was found with those calculated from the VIP-Man phantom. The S-values obtained in this work could help to improve the accuracy of absorbed dose in brain and head structures for positron-emitting radionuclides used in PET neuroimaging. • A multi-resolution whole-body phantom was constructed in MCNP code that include a complete set of head and brain structures. • A voxel phantom was constructed based on the ICRP-110 adult male reference phantom and on the Zubal head phantom. • Self-absorbed fractions (self-AFs) and S-values were calculated for seven positron-emitting radionuclides. • The constructed ICRP-head phantom provides a more accurate representation of the head and brain structures. [ABSTRACT FROM AUTHOR]

This article, titled "OC21.05: Assessing racial disparities in sonographic detection of endometrial cancer," compares the effectiveness of different methods (transvaginal sonogram, sonohysterogram, and endometrial aspiration) in detecting endometrial cancer or hyperplasia (ECH) between black and non-black women. The study included 1,840 women over the age of 50 who underwent endometrial evaluation. The results showed that there were no significant racial disparities in the detection rates of ECH between black and non-black women. However, the completion rate of transvaginal sonograms was lower in black women compared to non-black women, with fibroids negatively impacting the likelihood of completion. [Extracted from the article]

To evaluate the performance of transvaginal sonogram (TVS), sonohysterogram (SIS) and endometrial aspiration (EA) in detecting type 2 (T2) endometrial cancers (EC), compared to type 1 (T1) EC. Conclusions TVS, SIS and EA had excellent T2EC detection rates which were similar or better than for T1EC. Methods failure rates: T1EC - TVS 6.6%, SIS 1.6%, EA 1.6%; T2EC - TVS 17.9%, SIS 0.0%, EA 7.1%. [Extracted from the article]

A correction to the article "Simultaneous Measurement of Nanoscale Electric and Magnetic Optical Fields," that was published in the December 15, 2013 issue is presented.

Hurricanes, tsunamis, rogue waves and tornadoes are rare natural phenomena that embed an exceptionally large amount of energy, which appears and quickly disappears in a probabilistic fashion. This makes them difficult to predict and hard to generate on demand. Here we demonstrate that we can trigger the onset of rare events akin to rogue waves controllably, and systematically use their generation to break the diffraction limit of light propagation. We illustrate this phenomenon in the case of a random field, where energy oscillates among incoherent degrees of freedom. Despite the low energy carried by each wave, we illustrate how to control a mechanism of spontaneous synchronization, which constructively builds up the spectral energy available in the whole bandwidth of the field into giant structures, whose statistics is predictable. The larger the frequency bandwidth of the random field, the larger the amplitude of rare events that are built up by this mechanism. Our system is composed of an integrated optical resonator, realized on a photonic crystal chip. Through near-field imaging experiments, we record confined rogue waves characterized by a spatial localization of 206 nm and with an ultrashort duration of 163 fs at a wavelength of 1.55 μm. Such localized energy patterns are formed in a deterministic dielectric structure that does not require nonlinear properties. [ABSTRACT FROM AUTHOR]

SEAS performance was calculated for both current ECH and for all ECH cases (including ECH that developed > 1 year after SEAS). Conclusions TVS, SIS and SEAS had excellent sensitivity and NPP for current ECH, but SA performed best overall. Evaluate Simultaneous Endometrial Aspiration and Sonohysterography (SEAS) as a method of detecting Endometrial Cancer and Hyperplasia (ECH) in Postmenopausal Bleeding (PMB). [Extracted from the article]

A comparison of transmission spectra from periodic, quasiperiodic, and randomly spaced slit arrays in thick gold films reveals resonant plasmonic excitations that arise solely due to the long-range order of the quasiperiodic structures. Specifically, first-order plasmonic resonances at the air-gold interface of the quasiperiodic arrays are identified at a broader range of wavelengths than those observed from periodic structures with the same average slit distance. Thus, a quasiperiodic plasmonic coupler that couples both visible and near-infrared light to surface plasmon polaritons is designed and demonstrated. [ABSTRACT FROM AUTHOR]