The dutch FOm/f approach to gender balance in physics

Almost 20 years ago, the Dutch Foundation for Fundamental Research on Matter (FOM) launched the FOm/f programme to encourage women to continue a career in physics after finishing their PhDs. As of 2016, 86% of the FOm/f laureates hold permanent positions in academic research, while 11 laureates have become full-time physics professors. Key to the success of the FOm/f programme is a customised personal approach. Since September 2015, FOM has been a partner in the European Horizon 2020 GENERA project, which aims to implement Gender Equality Plans customized for physics. The positive experience with the personal approach of the FOm/f programme and dedicated tenure-track programmes for women will be paramount for a future Gender Equality Plan for improving the gender balance in the physics community.</p

GENERA gender in physics days in Europe

The GENERA European Horizon 2020 project aims at designing and implementing gender equality plans customised for physics. The three-year project started in September 2015. GENERA's activities include the national Gender in Physics Day in each European country participating in the GENERA project. Typically, at these days, national physics managers, human resources managers, and gender equality policy officers meet with senior and early-career physicists to review the status quo and formulate recommendations for improving the gender balance in the national physics community. We will report on the recommendations of the first GENERA Gender in Physics Day organised in 2016 in the Netherlands.</p

Layering, freezing and re-entrant melting of hard spheres in soft confinement

Confinement can have a dramatic effect on the behavior of all sorts of particulate systems and it therefore is an important phenomenon in many different areas of physics and technology. Here, we investigate the role played by the softness of the confining potential. Using grand canonical Monte Carlo simulations, we determine the phase diagram of three-dimensional hard spheres that in one dimension are constrained to a plane by a harmonic potential. The phase behavior depends strongly on the density and on the stiffness of the harmonic confinement. Whilst we find the familiar sequence of confined hexagonal and square-symmetric packings, we do not observe any of the usual intervening ordered phases. Instead, the system phase separates under strong confinement, or forms a layered re-entrant liquid phase under weaker confinement. It is plausible that this behavior is due to the larger positional freedom in a soft confining potential and to the contribution that the confinement energy makes to the total free energy. The fact that specific structures can be induced or suppressed by simply changing the confinement conditions (e.g. in a dielectrophoretic trap) is important for applications that involve self-assembled structures of colloidal particles.Comment: 5 pages, 5 figure

Creating and Controlling Polarization Singularities in Plasmonic Fields

Nanoscale light fields near nanoplasmonic objects can be highly structured and can contain highly-subwavelength features. Here, we present the results of our search for the simplest plasmonic system that contains, and can be used to control, the smallest such optical feature: an optical singularity. Specifically, we study the field around subwavelength holes in a metal film and look for polarization singularities. These can be circular (C)-points, at which the polarization is circular, or linear (L)-lines, where the polarization is linear. We find that, depending on the polarization of the incident light, two or three holes are sufficient to create a wealth of these singularities. Moreover, we find for the two-hole system that C-points are created in multiples of eight. This can be explained using symmetry arguments and conservation laws. We are able to predict where these singularities are created, their index and the topology of the field surrounding them. These results demonstrate the promise of this plasmonic platform as a tool for studying and controlling fundamental properties of light fields and may be important to applications where control over these properties is required at the nanoscale

Creating and controlling polarization singularities in plasmonic fields

Nanoscale light fields near nanoplasmonic objects can be highly structured and can contain highly-subwavelength features. Here, we present the results of our search for the simplest plasmonic system that contains, and can be used to control, the smallest such optical feature: an optical singularity. Specifically, we study the field around subwavelength holes in a metal film and look for polarization singularities. These can be circular (C)-points, at which the polarization is circular, or linear (L)-lines, where the polarization is linear. We find that, depending on the polarization of the incident light, two or three holes are sufficient to create a wealth of these singularities. Moreover, we find for the two-hole system that C-points are created in multiples of eight. This can be explained using symmetry arguments and conservation laws. We are able to predict where these singularities are created, their index and the topology of the field surrounding them. These results demonstrate the promise of this plasmonic platform as a tool for studying and controlling fundamental properties of light fields and may be important to applications where control over these properties is required at the nanoscale

The dutch FOm/f approach to gender balance in physics

Almost 20 years ago, the Dutch Foundation for Fundamental Research on Matter (FOM) launched the FOm/f programme to encourage women to continue a career in physics after finishing their PhDs. As of 2016, 86% of the FOm/f laureates hold permanent positions in academic research, while 11 laureates have become full-time physics professors. Key to the success of the FOm/f programme is a customised personal approach. Since September 2015, FOM has been a partner in the European Horizon 2020 GENERA project, which aims to implement Gender Equality Plans customized for physics. The positive experience with the personal approach of the FOm/f programme and dedicated tenure-track programmes for women will be paramount for a future Gender Equality Plan for improving the gender balance in the physics community

GENERA gender in physics days in Europe

The GENERA European Horizon 2020 project aims at designing and implementing gender equality plans customised for physics. The three-year project started in September 2015. GENERA's activities include the national Gender in Physics Day in each European country participating in the GENERA project. Typically, at these days, national physics managers, human resources managers, and gender equality policy officers meet with senior and early-career physicists to review the status quo and formulate recommendations for improving the gender balance in the national physics community. We will report on the recommendations of the first GENERA Gender in Physics Day organised in 2016 in the Netherlands

Harmonics Generation by Surface Plasmon Polaritons on Single Nanowires

We present experimental observations of visible wavelength second- and third-harmonic generation on single plasmonic nanowires of variable widths. We identify that near-infrared surface plasmon polaritons, which are guided along the nanowire, act as the source of the harmonics generation. We discuss the underlying mechanism of this nonlinear process, using a combination of spatially resolved measurements and numerical simulations to show that the visible harmonics are generated via a combination of both local and propagating plasmonic modes. Our results provide the first demonstration of nanoscale nonlinear optics with guided, propagating plasmonic modes on a lithographically defined chip, opening up new routes toward integrated optical circuits for information processing

Core-Shell Plasmonic Nanohelices

We introduce core-shell plasmonic nanohelices, highly tunable structures that have a different response in the visible for circularly polarized light of opposite handedness. The glass core of the helices is fabricated using electron beam induced deposition and the pure gold shell is subsequently sputter coated. Optical measurements allow us to explore the chiral nature of the nanohelices, where differences in the response to circularly polarized light of opposite handedness result in a dissymmetry factor of 0.86, more than twice of what has been previously reported. Both experiments and subsequent numerical simulations demonstrate the extreme tunability of the core-shell structures, where nanometer changes to the geometry can lead to drastic changes of the optical responses. This tunability, combined with the large differential transmission, make core-shell plasmonic nanohelices a powerful nanophotonic tool for, for example, (bio)sensing applications.QN/Kuipers LabQN/Quantum Nanoscienc

Layering, freezing, and re-entrant melting of hard spheres in soft confinement

Confinement can have a dramatic effect on the behavior of all sorts of particulate systems, and it therefore is an important phenomenon in many different areas of physics and technology. Here, we investigate the role played by the softness of the confining potential. Using grand canonical Monte Carlo simulations, we determine the phase diagram of three-dimensional hard spheres that in one dimension are constrained to a plane by a harmonic potential. The phase behavior depends strongly on the density and on the stiffness of the harmonic confinement. While we find the familiar sequence of confined hexagonal and square-symmetric packings, we do not observe any of the usual intervening ordered phases. Instead, the system phase separates under strong confinement, or forms a layered re-entrant liquid phase under weaker confinement. It is plausible that this behavior is due to the larger positional freedom in a soft confining potential and to the contribution that the confinement energy makes to the total free energy. The fact that specific structures can be induced or suppressed by simply changing the confinement conditions (e.g., in a dielectrophoretic trap) is important for applications that involve self-assembled structures of colloidal particles