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Abstract The magnetic properties of permalloy-based trilayers of the form Py 0.8 Cu 0.2 /Py 0.4 Cu 0.6 /Py/IrMn were studied as the spacer layer undergoes a paramagnetic to ferromagnetic phase transition. We find the coupling between the free Py 0.8 Cu 0.2 layer and the exchange bias pinned Py to be strongly temperature-dependent: there is negligible coupling above the Curie temperature of the Py 0.4 Cu 0.6 spacer layer, strong ferromagnetic coupling below that temperature, and a tunable coupling between these extremes. Polarized neutron reflectometry was used to measure the depth profile of the magnetic order in the system, allowing us to correlate the order parameter with the coupling strength. The thickness dependence shows that these are interface effects with an inverse relationship to thickness, and that there is a magnetic proximity effect that enhances the Curie temperature of the spacer layer with characteristic length scale of about 7 nm. As a demonstration of potential functionality of such a system, the structure is shown to spontaneously flip from the antiparallel to parallel magnetic configuration once the spacer layer has developed long-range magnetic order. 

Despite a growing body of research on the outcomes of holistic admissions and eliminating standardized test score requirements throughout education, few have documented how organizations transition to holistic review. Implementation, however, may help explain variation in impacts of holistic admissions. This article draws upon theories of organizational routines to examine adoption of holistic review in 13 STEM PhD programs from five universities. We conducted 60- to 90-min interviews with admissions leaders, including a COVID-19 transcript review activity. Data reveal change is multilevel, involving new policy/structural, practice/cultural, and cognitive/interpretive routines, which carry promise for disrupting institutionalized inequities where the politics of changing these routines can be managed. We discuss implications for policy, organizational practice, and future research on academic evaluations.

 

Using analysis of variance on a sample consisting of 1,499 US students across 21 US PhD programs, we show that there is no significant difference in the time it takes US male and female physics PhD students to complete their degree programs. This result comes in spite of a statistically significant 18 percentile point gap in median GRE-P scores between genders. Additional analyses reveal that there is no statistical difference between US students reported as White, Black/Hispanic/Multiracial/Native American, and Asian. Expanding our sample to also include 1,143 Non-US students, we find a small but significant effect of citizenship status on time to PhD completion where the average time for Non-US students to complete a physics PhD is about two months less than their US student counterparts. These results show that in spite of known gaps in standardized admissions exams between genders, these differences are not reflected in subsequent graduate school performance. Our findings reinforce the need for graduate admissions committees to go beyond quantitative metrics and conduct a holistic assessment of an applicant's potential to perform research effectively and to earn a PhD. 

The use of the Physics GRE in graduate admissions has gained considerable attention in recent years. While studies have shown the problematic nature of the exam quantitatively, it is time that student experiences were also included in the discussion. In this qualitative study, we interviewed 69 current graduate physics and astronomy students about their process of deciding where to apply to graduate school. Physics GRE requirements played a substantial role in this decision, with 48 students mentioning the test as part of their process to narrow programs down to a personalized short-list. Participants discussed potential barriers (e.g., financial and travel) that affected some students, but not others, which created an unequal playing field for grad school applicants. Secondly, while the participants noticed a shift towards more departments having "optional'' GRE language, female student participants still felt the need to take and submit their Physics GRE scores, while male student participants truly saw "optional'' as optional. These results suggest that graduate programs requiring the Physics GRE are doing more than asking prospective graduate students to simply take a physics test, and that the use of 'optional' requirement language may be inadvertently disadvantaging the very students that they are trying to recruit. 

We provide statistical measures and additional analyses showing that our original analyses were sound. We use a generalized linear mixed model to account for program-to-program differences with program as a random effect without stratifying with tier and found the GRE-P (Graduate Record Examination physics test) effect is not different from our previous findings, thereby alleviating concern of collider bias. Variance inflation factors for each variable were low, showing that multicollinearity was not a concern. We show that range restriction is not an issue for GRE-P or GRE-V (GRE verbal), and only a minor issue for GRE-Q (GRE quantitative). Last, we use statistical measures of model quality to show that our published models are better than or equivalent to several alternates. 

Faculty members involved in graduate admissions decisions have to determine who will be offered admissions to their respective graduate programs. In this study, we interviewed faculty at four institutions who currently serve or have served on their program's graduate admissions committee. The focus of this study was twofold: first, to explore what qualities faculty value in graduate students and second, to identify what sources of evidence faculty utilize in determining if a student possesses a desired quality. Results from these interviews showed that while qualities such as content knowledge and programming skills were valued, non-cognitive qualities such as self-motivation, resilience, and self-learning were also highly desired. The faculty noted that while current admissions practices can easily identify if a student has taken certain coursework, they typically lack the means to quickly assess non-cognitive qualities, which must often be inferred from the contents of personal statements and letters of recommendation. These results suggest that transparency on the part of graduate programs to better advertise the qualities they desire will assist letter writers and students writing personal statements to increase the impact of their application materials. 

Physics departments are increasingly working to improve diversity in graduate programs by using more holistic strategies in their admission and retention practices. However, completion rates for traditionally underserved groups are still problematic. By understanding and accounting for faculty and student divergence on challenges faced in retention, graduate programs will be better equipped to enact change. In this study of two graduate programs (one physics and the other astrophysics), faculty and graduate students were asked why graduate students leave their program, and to identify ways to reduce attrition. While the goal of improving retention was shared between faculty and graduate students, their visions for how retention could be improved were not aligned. Faculty believed that retention could be improved by reforming admissions practices to select for students with attributes critical for success in graduate school, such as resilience. In contrast, the graduate students noted more systemic or socio-cultural factors as impacting retention. 

This study aims to understand the effectiveness of typical admissions criteria in identifying students who will complete the Physics Ph.D. Multivariate statistical analysis of roughly one in eight physics Ph.D. students from 2000 to 2010 indicates that the traditional admissions metrics of undergraduate grade point average (GPA) and the Graduate Record Examination (GRE) Quantitative, Verbal, and Physics Subject Tests do not predict completion as effectively admissions committees presume. Significant associations with completion were found for undergraduate GPA in all models and for GRE Quantitative in two of four studied models; GRE Physics and GRE Verbal were not significant in any model. It is notable that completion changed by less than 10% for U.S. physics major test takers scoring in the 10th versus 90th percentile on the Quantitative test. Aside from these limitations in predicting Ph.D. completion overall, overreliance on GRE scores in admissions processes also selects against underrepresented groups.