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Understanding many body systems is a key challenge in physics. Single atom resolved imaging techniques have unlocked access to microscopic correlations in ultracold quantum gases. However they cannot be used when the relevant length scales are obscured by the resolution of the detection technique. We present a matterwave magnification scheme, based on evolutions in optical potentials, tailored to magnify the wave function of atoms, such that all length scales can be resolved. To showcase this method, we image atoms in the strongly interacting regime, establishing a new way to characterize correlated systems., Comment: 7 pages, 4 figures

Concern about the state of literacy instruction in America's classrooms has recently exploded. As a result, policymakers, school system leaders, and teachers have increasingly sought to remake how children learn to read in order to improve literacy outcomes--a pursuit that has gained heightened urgency in the aftermath of the pandemic. This work, often referred to as the "science of reading," has taken many shapes, but all emphasize the use of phonics-based instruction and early intervention to improve early readers' foundational literacy skills. This report considers Oakland Unified School District's (OUSD) efforts to reimagine early literacy instruction to improve student outcomes and close gaps between historically marginalized students and their peers. This report presents findings from an in-depth look at early literacy tutoring in OUSD. This report sets out to understand the key features of the literacy tutoring program in practice, to examine the school- and districtwide conditions that shaped its efficacy and sustainability, and to explore how tutoring shaped students' literacy outcomes. Conclusions are based on a mixed-method study that included interviews with school and partner staff, a survey of literacy tutors, and and analysis of data on students' literacy outcomes. [This project was made possible by the generous support from The Oakland REACH.]

We present an optical aberration correction technique for ultracold quantum gas experiments which directly utilizes the quantum gas as a wavefront sensor. The direct use of the quantum gas enables correcting aberrations that are otherwise impractical to measure, e.g. introduced by vacuum windows. We report a root-mean-square precision and accuracy of 0.01{\lambda} and 0.03{\lambda}, respectively, and also show independently the reduction of aberrations through measurement of the trap frequency of our optical tweezer. These improvements were achieved for a tweezer size that is well below our imaging resolution. The present work is in particular intended to serve as a tutorial for experimentalists interested in implementing similar methods in their experiment., Comment: 11 pages, 6 figures

We realize a Laughlin state of two rapidly rotating fermionic atoms in an optical tweezer. By utilizing a single atom and spin resolved imaging technique, we sample the Laughlin wavefunction, thereby revealing its distinctive features, including a vortex distribution in the relative motion, correlations in the particles' relative angle, and suppression of the inter-particle interactions. Our work lays the foundation for atom-by-atom assembly of fractional quantum Hall states in rotating atomic gases.

Public schooling has always been politically fraught, but current disagreements over issues related to race, sexuality, gender, and COVID-19 have reached a tipping point. According to this report from the Center on Reinventing Public Education and RAND, half of school system leaders say that these disagreements are disrupting schooling. Almost one in three district leaders also said their educators had received verbal or written threats about politically controversial topics since fall 2021. The findings come from surveys issued to 300 district and charter network leaders and interviews with superintendents. Their responses shed light on how political polarization has affected classrooms and how districts are responding. This report presents results from the fall 2022 survey of the American School District Panel (ASDP). The ASDP is a research partnership between RAND and CRPE. The panel also collaborates with several other education organizations, including the Council of the Great City Schools and Kitamba, to help improve outcomes for students throughout the United States.

Hydrodynamics provides a successful framework to effectively describe the dynamics of complex many-body systems ranging from subnuclear to cosmological scales by introducing macroscopic quantities such as particle densities and fluid velocities. According to textbook knowledge, it requires coarse graining over microscopic constituents to define a macroscopic fluid cell, which is large compared to the interparticle spacing and the mean free path. In addition, the entire system must consist of many such fluid cells. The latter requirement on the system size has been challenged by experiments on high-energy heavy-ion collisions, where collective particle emission, typically associated with the formation of a hydrodynamic medium, has been observed with few tens of final-state particles. Here, we demonstrate emergence of hydrodynamics in a system with significantly less constituents. Our observation challenges the requirements for a hydrodynamic description, as in our system all relevant length scales, i.e. the system size, the inter-particle spacing, and the mean free path are comparable. The single particle resolution, deterministic control over particle number and interaction strength in our experiment allow us to explore the boundaries between a microscopic description and a hydrodynamic framework in unprecedented detail., Comment: 11 pages, 6 figures

Public education depends on expertise, work, money, and cooperation from multiple actors who have different interests and beliefs. These lead to competition and negotiation--in other words, politics. Failure to consider the politics of reform implementation and sustainability has doomed many promising K-12 school improvement initiatives. This paper analyzes more than 10 years of data on the implementation of the portfolio strategy to identify practical lessons on managing the politics of reform K-12 schools. Sustaining complex reforms like the portfolio strategy in a political environment requires leaders to: (1) Continually seek new supporters and renew the support of existing ones; (2) Expect and prepare for attacks and be alert to the unnecessary harms caused by their own actions, which bolster opposition; (3) Develop information strategies that document intermediate results, alert leaders to emergent problems and actively counter hostile narratives; (4) Be attentive to competing agendas and political liabilities within their own alliances; and (5) Prepare for leadership succession so that reforms have a chance to last long enough to make a difference. These observations challenge the conventional wisdom that sustainable reforms can be built only upon the percolating up of good ideas and initiatives from below. Reform leaders are essential to knitting together fragile coalitions who may be motivated by different goals and aligning new programs and initiatives--and politically reinforcing them over time--so their benefits can accumulate.

In the summer of 2020, it became clear to growing numbers of families and community organizations that COVID-19's unprecedented disruptions to public education would not subside in time for the coming school year. Facing the prospect of continued school closures and uncertain public health safeguards, families were forced to make new childcare arrangements, often at the expense of their employment, and had to navigate the stress of dislocation and isolation with little support from the institutions they had long relied upon. Across the country, some families devised their own solution: the pandemic pod. They brought together small groups of students and enlisted adults--hired instructors, or groups of parent volunteers--to supervise students and support their learning. In partnership with their funders, the Center on Reinventing Public Education launched a national initiative that brought together researchers from around the country to track and analyze the pandemic pod movement. Their goal was simple: to learn from the families, educators, and community-based organizations who stepped in during the crisis to solve urgent challenges and, along the way, invented educational solutions that could outlast the pandemic. This report is one part of that larger effort. It offers the first in-depth look at families' and educators' experiences with pandemic pods, drawing upon a national survey of 152 parents and 101 instructors who participated in a pod during the pandemic, and follow-up interviews with 62 survey respondents. The findings suggest that families and educators can carve new, promising paths forward when freed from the rules around how school is supposed to work. At the same time, some of pods' flexibility arose because they were disconnected from the rules and routines that typically govern school systems. While this could yield benefits for students and freed educators to work in ways they found fulfilling, it also meant that students and educators in pods were cut off from critical forms of support.

Despite decades of research that points to the importance of family and staff engagement, the average school district in the United States is not designed to empower families and teachers to shape school improvement. The COVID-19 pandemic offers an opportunity to change that. Pandemic-fueled disruption helped seed ideas with families and educators about how to improve schools, and stimulus funding requirements for public input gave them an opportunity to communicate their vision as part of historic federal investments in K-12 education. Between January 2020 and September 2021, the Center on Reinventing Public Education (CRPE) conducted interviews with parents and teachers in four New England high schools and analyzed district communication in 86 New England school systems. Echoing national trends, few school systems communicated their plans to engage families and educators around stimulus investments. Where they existed, engagement strategies were often inequitable and failed to give families and teachers the support they needed to offer actionable input. School systems interested in better approaches to engaging the public must not start from scratch. Past experiences of including educators, families, and communities in the work of school improvement offers many lessons and suggests new, creative strategies worth trying.

In partnership with the Barr Foundation, the Center on Reinventing Public Education conducted longitudinal interviews with ten teachers and seven parents across four school systems in Connecticut, Rhode Island, Maine, and Massachusetts between January and June of 2021. Our interviews expose how ill-equipped New England schools were to address adolescent well-being during the pandemic. Specifically, our interviews reveal that as adolescents suffered, under-resourced families looked to schools for help that didn't come. While teachers made heroic efforts, they reportedly felt unprepared to deliver the support students needed. And schoolwide efforts were often inconsistent or limited. States and districts should be using this as an opportunity to reassess how they support adolescents and their families. This doesn't require radical redesign, fancy technology, or additional staff. Schools can make important changes with the resources they currently have. Specifically, school systems should: (1) tap community assets to dramatically deepen supports for the well-being of young people and their families; (2) give teachers mentorship and support in social-emotional learning, not just training materials; and (3) use leadership and data to make sure social-emotional well-being a schoolwide priority.

Strong-field ionization, involving tunnel ionization and electron rescattering, enables femtosecond time-resolved dynamics measurements of chemical reactions involving radical cations. Here, we compare the formation of CH3S+ following the strong-field ionization of the isomers CH3SCN and CH3NCS. The former involves the release of neutral CN, while the latter involves an intramolecular rearrangement. We find the intramolecular rearrangement takes place on the single picosecond timescale and exhibits vibrational coherence. Density functional theory and coupled-cluster calculations on the neutral and singly ionized species help us determine the driving force responsible for intramolecular rearrangement in CH3NCS. Our findings illustrate the complexity that accompanies radical cation chemistry following electron ionization and demonstrate a useful tool for understanding the cation dynamics after ionization., Comment: Combined PDF file consisting of the main text (20 pages, 7 figures, 2 tables) and the supplementary material (7 pages, 1 figure, nuclear coordinates of the calculated molecular structures). This article has been accepted for publication in the Journal of Chemical Physics. After it is published, it will be found at https://doi.org/10.1063/5.0117875

In this brief, we set out to understand how unionization may or may not shape practices central to charter schools' ability to serve students. The study, an exploratory one, includes 29 interviews across eight schools that unionized four to six years ago. Our results point to areas of concern, optimism, and future research. We found: (1) Unionization may help codify systems for teacher development, but it could also undermine efforts to advance teacher effectiveness; (2) Unionization may help to address pay inequities between districts and charter schools, but at the risk of financial sustainability; and (3) How unionization plays out may hinge on teachers' choice of bargaining partner and the priorities they pursue in collective bargaining.

Since 2016 the Center on Reinventing Public Education has sought to learn from the work of organizations with navigator services and understand its implications for the K-12 education system. In this brief, we present findings from a preliminary analysis of 10 such organizations. The organizations profiled in this brief offer important lessons for addressing inequitable access in education choice. We found that all organizations engaged in three common activities to reach families furthest from opportunity and improve their access to a quality, good-fit education: (1) Develop relationships with families furthest from opportunity; (2) Help families make sense of their options; and (3) Address systemic inequities by supporting policy and practice to improve the quality of schools in a city. Families face more choice than ever in education, in the form of district magnets, charter schools, new graduation pathways, curricular options, and out-of-school learning options. But supports for families have not kept pace, especially for those who historically have not had access to quality learning experiences. School navigation services are one option for changing this reality. We recommend that to offer these services, organizations must: (1) Balance tradeoffs to reach families and sustain contact; (2) Participate in conversations to address systemic inequities; and (3) Develop services or seek public funds to financially sustain themselves.

Ultrafast science depends on different implementations of the well-known pump-probe method. Here we provide a formal description of ultrafast disruptive probing, a method in which the probe pulse disrupts a transient species that may be a metastable ion or a transient state of matter. Disruptive probing has the advantage of allowing simultaneous tracking of the yield of tens of different processes. Our presentation includes a numerical model and experimental data on multiple products resulting from the strong-field ionization of two different molecules, partially-deuterated methanol and norbornene. In combination with ion imaging and/or coincidence momentum imaging, or as complementary to atom-specific probing or ultrafast diffraction methods, disruptive probing is a particularly powerful tool for the study of strong-field laser-matter interactions., Comment: 9 pages, 5 figures, submitted for publication to PCCP

Neural Painters is a class of models that follows a GAN framework to generate brushstrokes, which are then composed to create paintings. GANs are great generative models for AI Art but they are known to be notoriously difficult to train. To overcome GAN's limitations and to speed up the Neural Painter training, we applied Transfer Learning to the process reducing it from days to only hours, while achieving the same level of visual aesthetics in the final paintings generated. We report our approach and results in this work.

Pairing is the fundamental requirement for fermionic superfluidity and superconductivity. To understand the mechanism behind pair formation is an ongoing challenge in the study of many strongly correlated fermionic systems. Cooper pairs are the key ingredient to BCS theory as the microscopic explanation of conventional superconductivity. They form between particles of opposite spin and momentum at the Fermi surface of the system. Here, we directly observe Cooper pairs in a mesoscopic two-dimensional Fermi gas. We apply an imaging scheme that enables us to extract the full in-situ momentum distribution of a strongly interacting Fermi gas with single particle and spin resolution. Our ultracold gas allows us to freely tune between a completely non-interacting, unpaired system and weak attractions, where we find Cooper pair correlations at the Fermi surface. When increasing the attractive interactions even further, the pairs gradually turn into deeply bound molecules breaking up the Fermi surface. Our mesoscopic system is closely related to the physics of nuclei, superconducting grains or quantum dots. With the precise control over interactions, particle number and potential landscape in our experiment, the observables we establish in this work provide a new approach to longstanding questions concerning not only such mesoscopic systems but also their connection to the macroscopic world., Comment: 19 pages, 12 figures

This paper studies the end-to-end construction of an NLP Knowledge Graph (KG) from scientific papers. We focus on extracting four types of relations: evaluatedOn between tasks and datasets, evaluatedBy between tasks and evaluation metrics, as well as coreferent and related relations between the same type of entities. For instance, F1-score is coreferent with F-measure. We introduce novel methods for each of these relation types and apply our final framework (SciNLP-KG) to 30,000 NLP papers from ACL Anthology to build a large-scale KG, which can facilitate automatically constructing scientific leaderboards for the NLP community. The results of our experiments indicate that the resulting KG contains high-quality information., Comment: Accepted in ACL 2021

Tasks, Datasets and Evaluation Metrics are important concepts for understanding experimental scientific papers. However, most previous work on information extraction for scientific literature mainly focuses on the abstracts only, and does not treat datasets as a separate type of entity (Zadeh and Schumann, 2016; Luan et al., 2018). In this paper, we present a new corpus that contains domain expert annotations for Task (T), Dataset (D), Metric (M) entities on 2,000 sentences extracted from NLP papers. We report experiment results on TDM extraction using a simple data augmentation strategy and apply our tagger to around 30,000 NLP papers from the ACL Anthology. The corpus is made publicly available to the community for fostering research on scientific publication summarization (Erera et al., 2019) and knowledge discovery., Comment: accepted at EACL 2021

In 2017 the Texas Education Agency (TEA) launched the Systems of Great Schools (SGS) initiative. With a combination of incentives and capacity building, SGS attempts to transform how school districts approach school improvement. It calls on districts to manage school performance in new ways, expand access to school choice options, and take a dynamic approach to managing their supply of schools. As one of TEA's partners said, SGS is "basically changing the operating system of the district." Unlike other recent improvement efforts, SGS has set out not to change individual schools, but entire systems. The promise of this approach rests on the hope that districts, in turn, will reinvent themselves in ways that enable them to eliminate low-performing schools and foster higher-performing schools to take their place. The policy environment in Texas has created conditions that may help realize those hopes. The combination of reprieve from potent state accountability, incentives to partner with external organizations to improve low-performing schools, additional capacity support and grant opportunities, and a strong but flexible framework for locally designed accountability systems help make SGS more appealing, and more feasible, for districts. These policy tools are not new, but the coordinated use of them to create meaningful incentives for districts to voluntarily make system-level changes should be of interest to state leaders elsewhere. Texas' initiative suggests several important lessons for other state leaders interested in adopting "middle-way" programs in other state agencies, which we list in this report: (1) New programs don't necessarily require large new departments, but benefit from creative reorganization and realignment of existing programs and resources toward new strategic goals; (2) While it's important to attend to the organizational and human side of change inside the state agency by finding ways to align with existing work and strategies, it's also crucial to secure political support from the top and outside to make and protect organizational and resource changes; and (3) Successful change efforts require clear communication about the shifts the state expects to make, what success looks like, and how they will support districts to get there. While sustained improvement in participating districts is not guaranteed with SGS, this account of TEA's early experience reimagining state-led change can inform efforts in other states in the post-No Child Left Behind era.

New legislation in California will allow school districts, such as Oakland Unified School District (OUSD), to consider the "financial and academic impact" when approving or denying applications for new charter schools. OUSD has been in fiscal distress in the past and faces fiscal challenges that continue to play out in classrooms across the city. Teachers and families are right to want solutions, but independent reviews show that charter schools are not the primary cause of Oakland's troubles. Indeed, as described in this brief, enrollment in the district's schools has stabilized and revenues are at historic highs. The authors explore evidence related to the causes of OUSD's financial crisis and why previous efforts to right the ship have failed. With a renewed focus, can Oakland reorient itself as a system of schools--with charter schools and the larger community as partners--that will attract families back to the city and help stabilize OUSD finances? This brief points to a possible path forward.