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Bottom-up grown nanostructures often suffer from significant dimensional inhomogeneity, and for quantum confined heterostructures, this can lead to a corresponding large variation in electronic properties. A high-throughput characterization methodology is applied to >15,000 nanoskived sections of highly strained GaAsP/GaAs radial core/shell quantum well heterostructures revealing high emission uniformity. While scanning electron microscopy shows a wide nanowire diameter spread of 540–60+60 nm, photoluminescence reveals a tightly bounded band-to-band transition energy of 1546–3+4 meV. A highly strained core/shell nanowire design is shown to reduce the dependence of emission on the quantum well width variation significantly more than in the unstrained case.

Is there a legitimate basis for religious exemptions from laws that prohibit gender identity discrimination on the basis of people’s beliefs? The author argues that much depends upon how gender dysphoria is understood. If it is seen as a problem requiring medical diagnosis and treatment, then arguably there is no religious basis for discrimination, except in a few situations where being a biological male or female is theologically essential to a particular role. Transgender identification, understood as a medical issue, fits within a belief system that God created two sexes of human beings, male and female. Within that belief system one can make room for an understanding that there are those who experience disorders of sex development and those who have such a profound sense of being born in the wrong body that they undertake steps toward medical transition to align their bodies, as far as possible, with the opposite sex. However, recent reinterpretations of what it means to be transgender involve an assertion that it should not be seen as a medical issue, that affirmation of a person’s self-declared gender identity, with or without having hormonal treatment or surgery, is a matter of human rights and that the law should recognize that people may have a gender that, however described, is nonbinary. These views rely on certain beliefs and positions that have a very weak basis in science. They challenge religious beliefs, which accord with mainstream scientific understanding, that human beings are intrinsically a sexually dimorphic species. People of faith need the freedom to reject beliefs that are incompatible with their worldviews. That does not mean that ill-treatment of someone on the basis of their gender identity can ever be justified; but it does support a religious exemption from a legal obligation to accept someone else’s self-declared gender identity. It is one thing to ask me to respect your beliefs about yourself. It is another to ask me to act toward you as if I share your beliefs.

Webb et al.'s study of Family Court judgements involving allegations of child sexual abuse has yielded much valuable statistical data. It demonstrates that only 12 per cent of fully contested cases where an allegation of sexual abuse is made result in a finding that a child is exposed to an unacceptable risk of sexual abuse. This commentary seeks to explain this low percentage by reference to the cohort of cases that fall for judicial determination in the Family Court. The fully contested cases are disproportionately those in which police, child protection department staff or independent evaluators have been unable to reach a clear view. Typically, these cases involve children under 7 years old. The Family Court is the “too hard basket” of the child protection system, and so the low level of findings of unacceptable risk is not necessarily indicative of systemic failure.

Axially stacked quantum dots (QDs) in nanowires (NWs) have important applications in nanoscale quantum devices and lasers. However, there is lack of study of defect-free growth and structure optimization using the Au-free growth mode. We report a detailed study of self-catalyzed GaAsP NWs containing defect-free axial GaAs QDs (NWQDs). Sharp interfaces (1.8-3.6 nm) allow closely stack QDs with very similar structural properties. High structural quality is maintained when up to 50 GaAs QDs are placed in a single NW. The QDs maintain an emission line width of

Objective: To examine laws in three Australian jurisdictions that prohibit therapy to change or suppress a person’s sexual orientation or gender identity. Conclusions: The laws in Victoria and the ACT provide inadequate protection for clinically appropriate psychiatric practice and may deprive patients of mental health care.

Continuous room temperature nanowire lasing from silicon-integrated optoelectronic elements requires careful optimisation of both the lasing cavity Q-factor and population inversion conditions. We apply time-gated optical interferometry to the lasing emission from high-quality GaAsP/GaAs quantum well nanowire laser structures, revealing high Q-factors of 1250 ± 90 corresponding to end-facet reflectivities of R = 0.73 ± 0.02. By using optimised direct–indirect band alignment in the active region, we demonstrate a well-refilling mechanism providing a quasi-four-level system leading to multi-nanosecond lasing and record low room temperature lasing thresholds (~6 μJ cm−2 pulse−1) for III–V nanowire lasers. Our findings demonstrate a highly promising new route towards continuously operating silicon-integrated nanolaser elements., Lasers: Record-breaking lasing nanowires Persistent short pulses of near-infrared laser light can be produced at record low thresholds using tiny nanowire lasers, suitable for small-scale optoelectronic devices, including optical computing chips. The technology has been developed and demonstrated by researchers in the UK, led by Patrick Parkinson at the University of Manchester. Their system is based on semiconducting nanowires composed of gallium arsenide phosphide and gallium arsenide. It combines both key functions of a laser in one material, as the gain medium that amplifies the light emission and the cavity medium for containing and manipulating the light. The researchers engineered the precise behavior of the nanowires to demonstrate highly optimized nano-lasing performance at room temperature lasing thresholds. Their work addresses and overcomes significant challenges that have been limiting developments in this promising field.

Nanowire lasers are sought for near-field and on-chip photonic applications as they provide integrable, coherent and monochromatic radiation. A wavelength-scale nanowire acts as both the gain medium and the cavity for the lasing action: the functional performance (threshold and wavelength) is therefore dependent on both the opto-electronic and crystallographic properties of each nanowire. However, scalable bottom-up manufacturing techniques often suffer from inter-nanowire variation, leading to, often dramatic, differences in yield and performance between individual nanowires. Establishing the relationship between manufacturing controls, geometric and material properties and the lasing performance is a crucial step towards optimisation, however, this is challenging to achieve experimentally due to the complex interdependance of such properties. Here, we present a high-throughput correlative approach to characterise over 5000 individual GaAsP/GaAs multiple quantum well nanowire lasers. Fitting the spontaneous emission provides the threshold carrier density, while coherence length measurements measures end-facet reflectivity. We show that the lasing wavelength and threshold are intrinsically related to the width of a single quantum well due to quantum confinement and bandfilling effects. Unexpectedly, there is no strong relationship between the properties of the lasing cavity (facet reflectivity and distributed losses) and the threshold: instead the threshold is negatively correlated with the non-radiative recombination lifetime of the carriers. This approach therefore provides an optimisation strategy that is not accessible through small-scale studies. The quality and width of the quantum wells limit the threshold of these nanowire lasers, rather than the cavity quality.

Optimizing nanowire laser performance is challenging due to wire-to-wire variation of the gain and cavity properties. Our data-led experimental approach harnesses this variation, demonstrating that the gain is the factor limiting the lasing thresholds.

There is a lot of controversy about section 38(3) of the Sex Discrimination Act 1984 (Cth) (‘SDA’) which permits discrimination by faith-based schools against students on the basis of their sexual orientation and gender identity. This article explains the background to this provision, which in its present form was the result of amendments in 2013. It also explains the problems that would arise if the subsection were repealed without making other amendments to the SDA. Faith leaders have consistently made it clear that they do not want the right to expel or discipline students on the basis of sexual orientation or gender identity and so support the repeal of s 38(3). However, other amendments are needed to protect the rights of faith-based schools. These are, in any event, necessary to buttress the (very doubtful) constitutional validity of the 2013 amendments insofar as they concern gender identity. There is also a need for broader changes to the SDA to address the confusion about how the law on gender identity applies to children and adolescents. It is unclear when a child gains a legally protected gender identity; whether a clinical diagnosis of gender dysphoria is needed; what respect needs to be given to the views of parents, even with a Gillick-competent adolescent; and what professional discretion can be exercised by school principals when they consider that supporting the social transition of an adolescent is not in his or her best interests. The SDA needs to be amended to make clear that it does not require schools to support and affirm the ‘social transition’ of a young person against the wishes of a parent or when the school considers in good faith that this is not in the best interests of the young person. Difficult pastoral issues need to be left to professional judgment, drawing upon the best advice available from the young person’s treating medical and mental health practitioners.

Semiconductor nanowire lasers have long been proposed as elements for on-chip photonics, integrated optoelectronic circuitry, post-von Neumann computing and biological applications. They provide localised sources of coherent optical radiation, and can be fabricated from a wide variety of material systems using many growth techniques. Uniting this topic is the use of nanowires as an integrated cavity, waveguide and gain material. In this chapter, the common features of nanowire lasers are described: the underlying laser physics, the design rules for cavity and gain material and contemporary fields of research including optical coupling and plasmonics. An overview of key theoretical developments, experimental demonstrations and outstanding challenges is given.

The informed consent model of care for people who identify as transgender is predicated on the idea that a careful mental health assessment and a formal diagnosis of gender dysphoria are not necessary preconditions before starting a person on cross-sex hormones. This article considers the legality of the informed consent model in relation to adolescents under 18 in Australia in the light of the decisions of the Family Court in Re Kelvin (2017) 327 FLR 15; [2017] FamCAFC 258 (Re Kelvin) and Re Imogen (No 6) (2020) 61 Fam LR 344; [2020] FamCA 761. The approach taken by the Family Court is predicated on the treatment being a response to a clinically diagnosed disorder, diagnosed after proper assessment. Re Kelvin indicates that assessment and treatment should be conducted by a multidisciplinary team in accordance with internationally recognised standards and guidelines. For these reasons, practising under an informed consent model of care without a mental health assessment or working within a multidisciplinary team, is unlawful.

Controllable doping in semiconductor nanowires is essential for development of optoelectronic devices. Despite great progress, a fundamental challenge remains in controlling the uniformity of doping, particularly in the presence of relatively high levels of geometrical inhomogeneity in bottom-up growth. A relatively high doping level of 1E18 cm-3 corresponds to just ~1000 activated dopants in a 2µm long, 50nm diameter nanowire. High-throughput photoluminescence spectroscopy enables the collection of doping distributions across many (>10k) nanowires, but geometric variation adds additional uncertainty to the modelling. We present an approach that uses large datasets of doping and emission intensity to infer both doping and diameter across a growth, and apply Bayesian methods to study the underlying distributions in Zn-doped aerotaxy-grown GaAs nanowires. This new big-data enabled approach provides a route to exploit inherent inhomogeneity to reveal fundamental recombination mechanisms.

Semiconductor nanowire lasers are single-element structures that can act as both gain material and cavity for optical lasing. They have typical dimensions on the order of an optical wavelength in diameter and several micrometres in length, presenting unique challenges for testing and characterisation. Optical microscopy and spectroscopy are powerful tools used to study nanowire lasers; here, we review the common techniques and analytical approaches often used and outline potential pitfalls in their application. We aim to outline best practise and experimental approaches used for characterisation of the material, cavity and lasing performance of nanowires towards applications in biology, photonics and telecommunications.

Micro-photoluminescence maps reveal micron-scale spatial variation in intensity, peak emission energy and bandwidth across InGaN/GaN quantum wells. To investigate the effect of this spatial variation on measurements of the dependence of emission efficiency on carrier density, excitation power-dependent emission was collected from a bright and dark region on each of blue-and green emitting samples. The onset of efficiency droop was found to occur at a greater carrier density in the dark regions than in the bright, by factors of 1.2 and 1.8 in the blue and green-emitting samples, respectively. By spatially integrating the emission from progressively larger areas, it is also shown that collection areas greater than ∼50 μm in diameter are required to reduce the intensity variation to less than 10%.

Perovskite colloidal nanocrystals have emerged as important new optical materials, with tuneable light emission across the visible spectrum, narrow linewidths for high colour purity, and quantum efficiencies approaching unity. These materials can be solution processed in large volumes at low cost making them promising for optoelectronic devices. The structure of nanocrystals influences the radiative and non-radiative recombination of carriers within them through trap states and Auger recombination. To optimise the emission properties it is vital to understand the relationship between the optical emission of individual nanocrystals and their structure, size, and composition. Here, we use nano-cathodoluminescence to relate the nanoscale optical emission of individual inorganic perovskite nanocrystals to their size. This approach reveals that larger nanocrystals exhibit brighter luminescence, indicating lower non-radiative losses compared to smaller nanocrystals. We also show nanoscale colour mixing with bright red and blue emission from individual CsPbI3 and CsPbCl3 nanocrystals respectively in mixed films. The optical and structural characterisation serve as a powerful approach to the study of colloidal semiconductor nanocrystals that improves the fundamental understanding of quantum structures leading to improved optoelectronic devices.

Fluence-dependent photoluminescence and ultrafast transient absorption spectroscopy are used to study the dynamic behavior of carriers in CsPbCl3 perovskite nanocrystals. At low excitation fluences, the radiative recombination rate is outcompeted by significant trapping of the charge carriers which then recombine non-radiatively, resulting in weak photoluminescence. As fluence is increased, the saturation of trap states deactivates these non-radiative relaxation paths giving rise to an increase in photoluminescence at first. However, with further increases in fluence, Auger recombination of multiexcitons results in a decline in photoluminescence efficiency. Analysis of this behavior yields an absorption cross-section at 400 nm (3.1 eV) of 0.24 ± 0.05 x 10-14 cm2. Transient photoluminescence and absorption measurements yielded values for single exciton trapping lifetime (1.6 ± 0.7 ns), biexciton and trion lifetimes (20 ± 3 ps and 157 ± 20 ps, respectively), single exciton radiative lifetime (12.7 ± 0.2 ns), intraband cooling lifetime (290 ± 37 fs) and exciton-exciton interaction energy (10 ± 2 meV).

Nominal dopant-free zinc blende twinning superlattice InP nanowires have been grown with high crystal-quality and taper-free morphology. Here, we demonstrate its superior optical performance and clarify the different carrier recombination mechanisms at different temperatures using a time resolved photoluminescence study. The existence of regular twin planes and lateral overgrowth do not significantly increase the defect density. At room temperature, the as-grown InP nanowires have a strong emission at 1.348 eV and long minority carrier lifetime (∼3 ns). The carrier recombination dynamics is mainly dominated by nonradiative recombination due to surface trapping states; a wet chemical etch to reduce the surface trapping density thus boosts the emission intensity and increases the carrier lifetime to 7.1 ns. This nonradiative recombination mechanism dominates for temperatures above 155 K, and the carrier lifetime decreases with increasing temperature. However, radiative recombination dominates the carrier dynamics at temperature below ∼75 K, and a strong donor-bound exciton emission with a narrow emission linewidth of 4.5 meV is observed. Consequently, carrier lifetime increases with temperature. By revealing carrier recombination mechanisms over the temperature range 10-300 K, we demonstrate the attraction of using InP nanostructure for photonics and optoelectronic applications.

Ion migration is a characteristic feature of organic–inorganic halide perovskites. Importantly, migration of ion vacancies or adsorbed external ions can be manipulated by illumination, and this light-induced ion diffusion can enhance the internal quantum efficiency by reducing the density of charge trap sites. Here, the role of oxygen and halide ions on energy dynamics is investigated by performing in situ measurements of ion diffusion from the air-perovskite interface into the bulk. By correlating temporally, spatially, and spectrally-resolved optical microscopy with high spatial resolution secondary ion mass spectroscopy, it is shown that changes in local photoluminescence are caused by light-induced ion migration with a clear grain-size dependence related to surface-area to volume ratio. As a result, the charge carrier dynamics evolve from low luminescing defect-assisted monomolecular recombination to bright bimolecular recombination under illumination. These findings unambiguously link atomic diffusion to local radiative efficiency in spatially inhomogeneous films, and provide a route to high quantum efficiency through ion distribution engineering.

III-V semiconductor nanowires allow easy hetero-integration of optoelectronic components onto silicon due to efficient strain relaxation, well-understood design approaches and scalability. However continuous room temperature lasing has proven elusive. A key challenge is performing repeatable single-wire characterization { each wire can be different due to local growth conditions present during bottom-up growth. Here, we describe an approach using large-scale population studies which exploit inherent inhomogeneity to understand the complex interplay of geometric design, crystal structure, and material quality. By correlating nanowire length with threshold for hundreds of nanowire lasers, this technique reveals core-reabsorption as the critical limiting process in multiple-quantum-well nanowire lasers. By incorporating higher band-gap nanowire core, this effect is eliminated, providing reflectivity dominated behavior.

Material and functional stability remains a major issues in field of perovskite photovoltaics. To achieve a long device lifetime, it is crucial that we understand and optimize the lifetime of the material itself. One-step antisolvent processing is a facile method to enhance stability. Herein, we report that changes in the degradation process of perovskite films is modified by the antisolvent treatment in comparison to the conventional film without the process which we measure by monitoring the emission. Perovskite films prepared with anti-solvent processing have improved film morphology and reduced evolution of surface metallic lead, which correlated with improved film lifetimes.

Semiconductor nanowire (NW) lasers are a promising technology for the realisation of coherent optical sources with extremely small footprint. To fully realize their potential as building blocks in on-chip photonic systems, scalable methods are required for dealing with large populations of inhomogeneous devices that are typically randomly distributed on host substrates. In this work two complementary, high-throughput techniques are combined: the characterisation of nanowire laser populations using automated optical microscopy, and a high accuracy transfer printing process with automatic device spatial registration and transfer. In this work a population of NW lasers is characterised, binned by threshold energy density and subsequently printed in arrays onto a secondary substrate. Statistical analysis of the transferred and control devices show that the transfer process does not incur measurable laser damage and the threshold binning can be maintained. Analysis is provided on the threshold and mode spectra of the device populations to investigate the potential for using NW lasers for integrated systems fabrication., Comment: 18 pages, 7 figures

In 2019, the Tasmanian Parliament made major changes to the law, allowing a person to register a gender (which could be male, female, non-binary or another descriptor) and thereby to amend their birth certificate. This could be based upon nothing more than self-identification. Such laws have been enacted elsewhere in Australia and in other parts of the world. It is argued that the new laws reflect ideas about gender that are in radical discontinuity with the medical model on which the law concerning registration of a change of gender was previously based. The Tasmanian legislation is of international interest because it goes further than other laws by stipulating that a person who changes their gender identification is, for the purposes of Tasmanian law, to be treated as being of that gender. It follows that if someone declares themselves to be 'non-binary' or 'agender' then for a great variety of legal purposes, they must be so regarded. The difficulty is that these new ideas have been grafted onto a statute book which assumes there are only two sexes, male and female. The result is legislative incoherence. There are lessons in this for other jurisdictions around the world. Policy decisions have to be made about when distinctions in the law should be based upon biological sex and when they should be based on self-identified gender. The whole statute book needs to be considered in order to ensure that changes create consistent effects across different areas of application.

This article reviews the long battle to reform Australia’s custody and access laws between 1995 and 2011. The result is a law which strongly encourages courts to consider the option of shared physical custody, while also emphasizing the need to protect children from harm, not least from being exposed to family violence. The trench warfare over the text of the legislation between advocacy groups has now largely ceased. Good empirical research on the outcomes of reforms to the family law system assisted in clarifying the issues. However, the role of law in shaping parenting arrangements after separation should not be exaggerated. We can believe too much in law; and therefore, believe too much in law reform.

This article is based upon the findings of a five-year prospective longitudinal study of relocation disputes in Australia, involving interviews with 80 parents and 33 children in 70 families. In the five years following the relocation dispute, much changed for some of these families. A few mothers left without their children; several mothers returned to the original location; some fathers followed. There were also changes in some custody arrangements. The mothers who moved were not surprisingly satisfied with the outcome; however, even mothers who were not allowed to move mostly showed greater improvements in stress levels and mental health than fathers over the five year period, even if the fathers successfully opposed the move. Several mothers adapted to staying if they could see the benefit to their children. All children who moved adapted to the new location and made new friends; however, those who had close relationships with their father found it very hard to be a long distance from him. Drawing upon these interviews, it is argued that decision making in relocation cases must be resolutely child-centered. It cannot be based upon adults’ rights. Children usually benefit from a continuing relationship with a nonresident parent who wants to be involved in their lives. In the adjudication of relocation disputes, careful attention is needed to how close and how developmentally important the child’s relationship is with their nonresident parent. Consideration must also be given to whether the nonresident parent can move to the preferred location of the primary caregiver.

Both gain medium design and cavity geometry are known to be important for low threshold operation of semiconductor nanowire lasers. For many applications nanowire lasers need to be transferred from the growth substrate to a low-index substrate; however, the impact of the transfer process on optoelectronic performance has not been studied. Ultrasound, PDMS-assisted and mechanical rubbing are the most commonly used methods for nanowire transfer; each method may cause changes in the fracture point of the nanowire which can potentially affect both length and end-face mirror quality. Here we report on four common approaches for nanowire transfer. Our results show that brief ultrasound and PDMS-assisted transfer lead to optimized optoelectronic performance, as confirmed by ensemble median lasing threshold values of 98 and 104 μJ cm

Coaxial quantum wells (QWs) are ideal candidates for nanowire (NW) lasers, providing strong carrier confinement and allowing close matching of the cavity mode and gain medium. We report a detailed structural and optical study and the observation of lasing for a mixed group-V GaAsP NW with GaAs QWs. This system offers a number of potential advantages in comparison to previously studied common group-V structures (e.g., AlGaAs/GaAs) including highly strained binary GaAs QWs, the absence of a lower band gap core region, and deep carrier potential wells. Despite the large lattice mismatch (∼1.7%), it is possible to grow defect-free GaAs coaxial QWs with high optical quality. The large band gap difference results in strong carrier confinement, and the ability to apply a high degree of compressive strain to the GaAs QWs is also expected to be beneficial for laser performance. For a non-fully optimized structure containing three QWs, we achieve low-temperature lasing with a low external (internal) threshold of 20 (0.9) μJ/cm2/pulse. In addition, a very narrow lasing line width of ∼0.15 nm is observed. These results extend the NW laser structure to coaxial III-V-V QWs, which are highly suitable as the platform for NW emitters.

This chapter explores the different ways that children can participate in custody and child protection cases. It is not only articulate older children and young people who ought to have an input into decisions. Children can “speak” in a variety of ways, and not only through words. To allow them to participate effectively, adults need to assist them through “scaffolding” their participation. Hearing the voice of the child also involves dilemmas. Children may not want to be involved for a variety of different reasons, some of which they may not feel free to disclose. The chapter concludes by offering four principles about how to hear from children in cases involving parenting arrangements.

This paper provides some background to the final report of the Australian Law Reform Commission on reforms to family law and reviews some of the key recommendations. It is argued that while simplification of Part VII of the Act, concerning parenting after separation, will be beneficial, no case has been made out for the wholesale abandonment of the 2006 reforms. The law has an educative role, particularly for those who need some assistance from lawyers and mediators in order to agree upon parenting arrangements. The proposed property reforms are modest, and do not go far enough to inject some principle, coherence and order into the law; however, they are a good start. Some refinements are proposed. The case management proposals have real potential to address unethical adversarial conduct by a minority of lawyers. It is argued that it is important that the family law profession engage constructively with the proposals. The position that few if any reforms are needed is an untenable one. Working to implement beneficial change will be better than having less well-thought out proposals thrust upon the profession.

Both gain medium design and cavity geometry are known to be important for low threshold operation of semiconductor nanowire lasers. For many applications nanowire lasers need to be transferred from the growth substrate to a low-index substrate; however, the impact of the transfer process on optoelectronic performance has not been studied. Ultrasound, PDMS-assisted and mechanical rubbing are the most commonly used methods for nanowire transfer; each method may cause changes in the fracture point of the nanowire which can potentially affect both length and end-face mirror quality. Here we report on four common approaches for nanowire transfer. Our results show that brief ultrasound and PDMS-assisted transfer lead to optimized optoelectronic performance, as confirmed by ensemble median lasing threshold values of 98 and 104 μJ cm−2 respectively, with nanowires transferred by ultrasound giving a high lasing yield of 72%. The mean threshold difference between samples is shown to be statistically significant: while a significant difference in mean length from different transfer methods is seen, it is shown by SEM that end-facet quality is also affected and plays an important role on threshold gain for this nanowire architecture.

Currently, there are certain provisions in Australian law that exempt faith-based organisations from the operation of laws that prohibit discrimination on grounds of gender identity or 'being transgender'. This paper explores whether there is a religious basis for discrimination on the ground of gender identity, with particular reference to how faith-based schools make decisions about children and young people who seek to transition to a new gender identity – with or without parental agreement. While it has long been the case that a very small proportion of people, from early childhood right through to adulthood, identify as feeling they are of the opposite sex, there are reasons to be concerned about the number of adolescents who are now claiming to be 'transgender' – especially natal females. The research indicates that many of these children and young people have multiple mental health problems or are on the autism spectrum, and may have experienced abuse and other adverse life events. There is also some evidence for social contagion amongst friendship groups. The etiology of transgender identification remains poorly understood from a medical perspective. Identification with a gender identity different to natal sex is often accompanied by various beliefs that are incapable of either validation or falsification by science. These include that biological sex and gender are two different things; that gender is what you feel, that gender is fluid, and that it is possible to be “non-binary”. These beliefs conflict not only with religious understandings of the created order, but also with a mainstream understanding that gender is innate and people are not just 'assigned' a gender at birth. The Christian response to children or young people who are experiencing gender identity issues must be pastoral and compassionate, and focused on their best interests; but this does not mean agreeing with their beliefs. There is thus a basis for a religious exemption to prohibitions on discrimination based upon gender identity, if the law is understood to require that the person be accepted as the gender with which they now identify. However, if the law is understood as requiring only that a person should not engage in discriminatory conduct (for example refusing service in a restaurant), then there is no valid basis for a religious exemption. Beyond the issue of religious exemptions, there are compelling reasons not to legislate that any professional working with children or young people has to accept a young person’s self-identified gender identity against his or her professional judgment. Schools need to be free to adopt a pastoral approach, guided by appropriate health professionals, and based upon their assessment of what is in the best interests of the child or young person.

The structural and functional properties of organic heterojunctions play a vitally important role in the operation of organic devices, but their properties are difficult to measure directly due to the buried interfaces that are typically formed. We have grown model heterojunctions consisting of two monolayer-thick organic semiconductors and used these bilayers to explore the two-dimensional dynamics of excitons. The heterostructures are formed by sequential deposition of monolayers of perylene-3,4,9,10-tetracarboxylic-3,4,9,10-diimide (PTCDI) and fullerene (C 60 ) on hexagonal boron nitride (hBN). The morphology of these bilayers was characterized using atomic force microscopy and showed clear differences in the C 60 growth kinetics on hBN and PTCDI. The variation in the fluorescence of PTCDI-C 60 heterostructures with increasing fullerene coverage showed a reduction in intensity consistent with exciton diffusion and quenching. We use a simple model for the intensity dependence to determine the two-dimensional exciton diffusion length in a PTCDI monolayer, finding a value of 17 ± 3 nm for this parameter.

The design of efficient graphene-silicon (GSi) Schottky junction photodetectors requires detailed understanding of the spatial origin of the photoresponse. Scanning-photocurrent-microscopy (SPM) studies have been carried out in the visible wavelengths regions only, in which the response due to silicon is dominant. Here we present comparative SPM studies in the visible ($\lambda$ = 633nm) and infrared ($\lambda$ = 1550nm) wavelength regions for a number of GSi Schottky junction photodetector architectures, revealing the photoresponse mechanisms for silicon and graphene dominated responses, respectively, and demonstrating the influence of electrostatics on the device performance. Local electric field enhancement at the graphene edges leads to a more than ten-fold increased photoresponse compared to the bulk of the graphene-silicon junction. Intentional design and patterning of such graphene edges is demonstrated as an efficient strategy to increase the overall photoresponse of the devices. Complementary simulations and modeling illuminate observed effects and highlight the importance of considering graphene's shape and pattern and device geometry in the device design.

Semiconductor nanowires suffer from significant non-radiative surface recombination, however, heavy p-type doping has proven to be a viable option to increase the radiative recombination rate and hence quantum efficiency of emission, allowing demonstration of room-temperature lasing. Using a large-scale optical technique, we have studied Zn-doped GaAs nanowires to understand and quantify the effect of doping on growth and lasing properties. We measure the non-radiative recombination rate (knr) to be (0.14 ± 0.04) ps−1 by modelling the internal quantum efficiency (IQE) as a function of doping level. By applying a correlative method, we identify doping and nanowire length as key controllable parameters determining lasing behavior, with reliable room-temperature lasing occurring for p &3 × 1018 cm−3 and lengths & 4 µm. We report a best-in-class core-only near-infrared nanowire lasing threshold of ∼ 10 µJ cm−2 , and using a data-led filtering step, we present a method to simply identify sub-sets of nanowires with over 90% lasing yield.

Detection of light in the near- and short-wave infrared spectral region is of great interest for applications ranging from imaging to sensing. However, silicon commonly employed for photodetectors is limited in its spectral range to wavelengths of 400… 1100nm due to its band gap of $\sim$1.1eV. Materials for light detection in the wavelength range $\gt1100$ nm are typically III-V-based semiconductors such as e.g. InGaAs which are difficult to integrate with CMOS technology, hindering use in main-stream applications due to technical issues and associated high cost. Here, we present graphene-silicon hybrid structure photodetectors which demonstrate an extended spectral detection range from $\sim$400… 1700nm.

The argument of this Article is that the width of discretion that trial judges have to alter property rights under the Family Law Act 1975 (Cth) (‘the Act’) has been overstated. The property aspects of the Act can only be valid to the extent to which the law is an appropriate application of the marriage and divorce powers in the Constitution or is within the boundaries of the States’ reference of powers about de facto relationships. These constitutional provisions place significant constraints upon judicial discretion. In relation to marriages, the need to adjust property rights must result from the circumstances of the marital relationship or be justified as a consequence of the financial impact upon a party of its breakdown. The authority of Parliament to make laws concerning the alteration of the property rights of de facto partners is limited to cases of relationship breakdown. Furthermore, the Family Court of Australia and the Federal Circuit Court of Australia are both Chapter III courts. That has implications for the kind of discretion that Parliament can lawfully confer upon the trial judge, and the limits of that discretion. Some recent dicta and decisions of the Full Court of the Court suggest a view of judicial discretion which, it is argued, is inconsistent with the nature of judicial power in a Chapter III court. The discretion of trial judges is fettered by three duties: The duty to follow the interpretation of the Act as established authoritatively by appellate decisions, taking account of guidelines in appellate judgments; the duty to give reasons that explain the outcome of the case, and in particular, to justify the alteration of legal and equitable interests in specific items of property; and the duty to avoid arbitrary and capricious decision-making. The current jurisprudence on family property law is not necessarily consistent with these constitutional limitations.

INTRODUCTION The last 40 years or so have seen massive changes in family life in many post-Christian countries. Marriage is no longer the only accepted basis for family formation and, indeed, in many countries more children are born outside of marriage than within it. Ours is, to some extent, a post-marital age. What kinds of relationships, then, should be covered in default rules for property division if the relationship breaks down? These issues are explored through three vignettes: – Cameron and Sandra are in their mid-20s and are contemplating if and how to formalise their relationship. – Amir, a refugee from Afghanistan, is married to Sanaubar. They have three children together. He takes a second (de facto) wife, Basira, and they also have a child together. The relationship with Basira does not last. – Melissa has had a succession of relationships, including a failed marriage. She gains sole ownership of the former matrimonial home in the divorce. Then she lives with Jim for over five years in an intimate domestic relationship; but neither want to marry. Finances are kept separate. In the light of these vignettes, consideration is given to whether dyadic Judaeo-Christian marriage can remain the paradigm for a default law of property division on separation. THE EMERGENCE OF THE POST-MARITAL AGE The last 40 years have seen very rapid social change, especially in terms of family life and moral values about sexual behaviour in Western countries. New Zealand, it seems, is no exception to the patterns of change in post-Christian societies. The idea that many of these societies could actually be post-marital societies, as well as post-Christian societies, may at first be confronting. Marriage still remains reasonably popular as a basis for a long-term commitment amongst university-educated people in Western countries. It remains obligatory as the basis for family life in deeply religious communities. For many in the lesbian, bisexual, gay and transgender (LBGT) communities, achieving legal recognition of their relationships as marriages has been a fervently sought goal. However, as university-educated people moving in professional circles, we need to resist the temptation to see the world around us through the coloured glasses of those with whom we associate. For a large proportion of the population in Western societies, marriage is no longer seen as the conventional norm for founding a family.

III–V semiconductor nanowires combine the properties of III–V materials with the unique advantages of the nanowire geometry, allowing efficient room temperature photodetection across a wide range of photon energies, from a few eV down to meV. For example, due to their nanoscale size, these show great promise as sub-wavelength terahertz (THz) detectors for near-field imaging or detecting elements within a highly integrated on-chip THz spectrometer. We discuss recent advances in engineering a number of sensitive photonic devices based on III–V nanowires, including InAs nanowires with tunable photoresponse, THz polarisers and THz detectors.

In this work, we demonstrate novel THz detectors and modulators based on semiconductor nanowires. We show that single nanowire PC THz receivers exhibit excellent sensitivity, high SNR of 40, and a broad detection bandwidth up to 2 THz, comparable to the bulk InP PC receivers. We also demonstrate ultrafast THz modulation by GaAs nanowire polarisers with a less than 5ps switching time and a modulation depth of −8dB, We show an extinction of over 13% and dynamic range of −9dB, comparable to microsecond-switchable graphene- and metamaterial-based THz modulators.

Despite its widespread acceptance by medical investigators, the use of colposcopy to document ano-genital examinations after sexual assault allegations has attracted controversy. Concerns have been expressed about potentially negative effects arising from the misuse of photo-documentation with some arguing that colposcopic photo-documentation should not occur. We discuss the extent to which these concerns, so far as they relate to the medical examination of children and young people, are supported by the research evidence. We raise and answer four questions: are there negative impacts for children and young people from the use of colposcopy in the medical assessment of suspected child sexual assault? Does the use of colposcopy improve the reliability of the medical assessment? Does the use of colposcopy affect the outcomes in trials, and in particular, criminal prosecutions? Is there any legal or medical benefit to the retention of photo-documentation when the ano-genital examination reveals no abnormalities? We discuss whether the current practices in the use of colposcopy should continue, and what reforms to the law might be needed to protect against the misuse of photo-documentation of ano-genital examinations.

Child protection is a fundamental responsibility of government. There are many aspects of social life which could function well without government involvement. The extent to which the state should be involved in managing the economy, running industries, and even in providing a safety net for old age are issues on which political parties divide. The differences between the states and territories in terms of definitions of child abuse, and the different operating definitions used by welfare departments for the purposes of their own record keeping, have made it very difficult to gain a national picture concerning the known incidence of child abuse in Australia. Not only do the Australian jurisdictions vary enormously in the proportions of cases which are classified as emotional abuse, but the variations are significant in terms of the numbers per 1000 children. In New South Wales, the rate is 3.0 per 1000, and in Victoria, 2.2 per 1000, compared to a national average of 1.8.