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This report emphasizes the importance of state actions in improving educational opportunities for historically marginalized students, particularly those with disabilities. It highlights the existing achievement gaps and challenges faced by students with disabilities, especially those from minority groups. The report suggests that states have a critical role in strengthening charter schools' capacity to meet the needs of students with disabilities, but it also points out that the current state actions in this area have been limited, primarily focusing on ensuring compliance with laws rather than addressing resource gaps or improving educational outcomes.

The geometric characteristics of Bloch wave functions play a crucial role in electronic transport properties. We show that the thermoelectric performance of materials is governed by the geometric structure of Bloch wave functions within the framework of the Boltzmann equation. The essential geometric notion is the Hilbert-Schmidt quantum distance, measuring the resemblance between two quantum states. We establish a geometric characterization of the scattering rate by extending the concept of quantum distance between two states in momentum space at a distance.Employing isotropic quadratic band touching semimetals, where one can concentrate on the role of quantum geometric effects other than the Berry curvature, we find that the response functions for electrical quantum transport and, therefore, the thermoelectric power factor can be succinctly expressed in terms of the maximum quantum distance, $d_\mathrm{max}$. Specifically, when $d_\mathrm{max}$ reaches one, the power factor doubles compared to the case with trivial geometry ($d_\mathrm{max}=0$). Our finding highlights the significance of quantum geometry in improving the performance of thermoelectric devices.

We study the influence of the quantum geometry on the magnetic responses of quadratic band crossing semimetals. More explicitly, we examine the Landau levels, quantum Hall effect, and magnetic susceptibility of a general two-band Hamiltonian that has fixed isotropic quadratic band dispersion but with tunable quantum geometry, in which the interband coupling is fully characterized by the maximum quantum distance $d_\mathrm{max}$. By continuously tuning $d_\mathrm{max}$ in the range of $0\leq d_\mathrm{max}\leq 1$, we investigate how the magnetic properties of the free electron model with $d_\mathrm{max}=0$ evolve into those of the bilayer graphene with $d_\mathrm{max}=1$. We demonstrate that despite sharing the same energy dispersion $\epsilon(p) =\pm\frac{p^2}{2m}$, the charge carriers in the free electron model and bilayer graphene exhibit entirely distinct Landau levels and quantum Hall responses due to the nontrivial quantum geometry of the wave functions.

We propose a new band engineering scheme on the biphenylene network, a newly synthesized carbon allotrope. First, we investigate the mechanism for the appearance of type II Dirac fermion in a pristine biphenylene network. We show that the essential ingredients are mirror symmetries and the stabilization of the compact localized eigenstates via destructive interference. While the former is used for the band-crossing point along high symmetry lines, the latter makes the obtained Dirac dispersion highly inclined. Then, we demonstrate that many other different kinds of Dirac fermions, such as type-I Dirac, gapped type-II Dirac, and nodal line semimetals, can be developed by fluorinating the biphenylene network periodically in various ways. In this program, the key role of the fluorine atoms is manipulating the condition of the destructive interference and mirror symmetries.

In condensed matter physics, the Kagome lattice and its inherent flat bands have attracted considerable attention for their potential to host a variety of exotic physical phenomena. Despite extensive efforts to fabricate thin films of Kagome materials aimed at modulating the flat bands through electrostatic gating or strain manipulation, progress has been limited. Here, we report the observation of a novel $d$-orbital hybridized Kagome-derived flat band in Ag/Si(111) $\sqrt{3}\times\sqrt{3}$ as revealed by angle-resolved photoemission spectroscopy. Our findings indicate that silver atoms on a silicon substrate form a Kagome-like structure, where a delicate balance in the hopping parameters of the in-plane $d$-orbitals leads to destructive interference, resulting in a flat band. These results not only introduce a new platform for Kagome physics but also illuminate the potential for integrating metal-semiconductor interfaces into Kagome-related research, thereby opening a new avenue for exploring ideal two-dimensional Kagome systems., Comment: 7 pages, 4 figures

The localized nature of a flat band is understood by the existence of a compact localized eigenstate. However, the localization properties of a partially flat band, ubiquitous in surface modes of topological semimetals, have been unknown. We show that the partially flat band is characterized by a non-normalizable compact localized state(NCLS). The partially flat band develops only in a momentum range, where normalizable Bloch wave functions can be obtained by the linear combination of the NCLSs. Outside this momentum region, a ghost flat band, unseen from the band structure, is introduced for the consistent counting argument with the full set of NCLSs. Then, we demonstrate that the Wannier function corresponding to the partially flat band exhibits an algebraic($\sim 1/r^{1+\epsilon}$ in 1D and $\sim 1/r^{3/2+\epsilon}$ in 2D) decay behavior, where $\epsilon$ is a positive number. Namely, one can have the Wannier obstruction even in a topologically trivial band if it is partially flat. Finally, we develop a construction scheme of a tight-binding model of the topological semimetal by designing an NCLS.

As the COVID-19 pandemic continues, emerging evidence provides a deeper understanding of the pandemic's impact on the more than 8 million young people with disabilities. This includes youth who receive special education services under the Individuals with Disabilities Education Act (IDEA) or who qualify under the Rehabilitation Act of 1973 (Section 504) in the U.S. For this latest special-education paper, the authors reviewed more than 100 research reports, peer-reviewed journal articles, news stories, and summaries of legal cases. They also reviewed the U.S. Department of Education's website and state websites. The evidence collected includes quantitative and qualitative research findings, themes from news stories, outcomes of lawsuits, and policy guidance. Together, this evidence shows that the ongoing challenges of the pandemic compounded and further complicated the educational experiences of students with disabilities. This report is the second installment of an updated set of papers that assess the best available evidence on how the COVID-19 pandemic has affected America's students. [For the previous report, "How Has the Pandemic Affected Students with Disabilities? A Review of the Evidence to Date," see ED615189.]

A singular flat band(SFB), a distinct class of the flat band, has been shown to exhibit various intriguing material properties characterized by a geometric quantity of the Bloch wave function called the quantum distance. We present a general construction scheme for a tight-binding model hosting an SFB, where the quantum distance profile can be controlled. We first introduce how to build a compact localized state(CLS), a characteristic eigenstate of the flat band, providing the flat band with a band-touching point, where a specific value of the maximum quantum distance is assigned. Then, we develop a scheme designing a tight-binding Hamiltonian hosting an SFB starting from the obtained CLS, satisfying the desired hopping range and symmetries by applying the construction scheme. While the scheme can be applied to any dimensions and lattice structures, we propose several simple SFB models on the square and kagome lattices. Finally, we establish a bulk-boundary correspondence between the maximum quantum distance and the boundary modes for the open boundary condition, which can be used to detect the quantum distance via the electronic structure of the boundary states., Comment: 10 pages, 6 figures

The role of robots is expanding from tool to collaborator. Socially assistive robots (SARs) are an example of collaborative robots that assist humans in the real world. As robots enter our social sphere, unforeseen risks occur during human-robot interaction (HRI), as everyday human space is full of uncertainties. Risk introduces an element of trust, so understanding human trust in the robot is imperative to initiate and maintain interactions with robots over time. While many scholars have investigated the issue of human-robot trust, a significant portion of that discussion is rooted in the human-automation interaction literature. As robots are no longer mere instruments, but social agents that co-exist with humans, we need a new lens to investigate the longitudinal dynamic nature of trust in HRI. In this position paper, we contend that focusing on the dynamic nature of trust as a new inquiry will help us better design trustworthy robots., Comment: Accepted at ACM CHI Conference workshop, WS32: Socially Assistive Robots as Decision Makers: Transparency, Motivations, and Intentions

It is known that materials with broken time-reversal symmetry can have Hall response. Here we show that in addition to the conventional currents, a new type of nonlinear Hall current can occur in the time-reversal breaking materials within the second-order response to in-plane electric and vertical magnetic fields. Such a Hall response is generated by the oscillation of the electromagnetic field and has a quantum origin arising from a novel dipole associated with the Berry curvature and band velocity. We demonstrate that the massive Dirac model of LaAlO3/LaNiO3/LaAlO3 quantum well can be used to detect this Hall effect. Our work widens the theory of the Hall effect in the time-reversal breaking materials by proposing a new kind of nonlinear electromagnetic response., Comment: 6 pages, 4 figures

We investigate the origin of the ubiquitous existence of flat bands in the network superstructures of atomic chains, where one-dimensional(1D) atomic chains array periodically. While there can be many ways to connect those chains, we consider two representative ways of linking them, the dot-type and triangle-type links. Then, we construct a variety of superstructures, such as the square, rectangular, and honeycomb network superstructures with dot-type links and the honeycomb superstructure with triangle-type links. These links provide the wavefunctions with an opportunity to have destructive interference, which stabilizes the compact localized state(CLS). The CLS is a localized eigenstate whose amplitudes are finite only inside a finite region and guarantees the existence of a flat band. In the network superstructures, there exist multiple flat bands proportional to the number of atoms of each chain, and the corresponding eigenenergies can be found from the stability condition of the compact localized state. Finally, we demonstrate that the finite bandwidth of the nearly flat bands of the network superstructures arising from the next-nearest-neighbor hopping processes can be suppressed by increasing the length of the chains consisting of the superstructures., Comment: 8pages, 4figures

The COVID-19 pandemic has disrupted education around the world and created extraordinary new challenges for students, families, educators, and policymakers. Its impacts on students' learning and well-being are far reaching, though not yet fully understood. However, early evidence indicates disproportionate effects on students with disabilities, a diverse group of seven million young people, or 14 percent of all U.S. students. Prolonged school closures separated many students with disabilities from the hands-on instructional supports and physical or cognitive therapies set forth by their Individualized Education Programs (IEPs) and adapting online learning platforms to ensure accessibility by students with a range of disabilities proved challenging for many educators and districts. While nearly all students have struggled to keep pace in 2020 and 2021, those who rely on specialized supports during ordinary times were doubly disadvantaged. In June of 2021, the Center on Reinventing Education (CRPE) and the Center for Learner Equity gathered a panel of seven experts in educating students with disabilities to assess and reflect on current research. This paper offers an agenda for researchers, policymakers, practitioners, and the philanthropic community in the years ahead. Perhaps the clearest takeaway from the review is the urgent need to know more about the experiences of students with disabilities.

The subject of public charter schools and students with disabilities is both important and sensitive. These students have the potential to benefit greatly from the smaller size and specialized focus of many public charter schools, but questions persist regarding whether all or even most charters are as receptive to enrolling students with disabilities as they are to serving students who do not have disabilities. Furthermore, do differences in enrollment of students with disabilities explain differences in funding between the two sectors? To shine a brighter light on this vital question, we have conducted a careful study of the funding surrounding the education of students with disabilities in public charter schools using data from fiscal year 2018 in 18 cities where charters hold a substantial share of K-12 education enrollment. This report provides a summary of our findings. Additional details regarding how special education services are provided to students with disabilities in each of our 18 cities are provided in a separate Appendix of City Snapshots. As public schools, charter schools must adhere to the same federal legal requirements as their traditional public school (TPS) counterparts. When charters are their own local education agency (LEA), the charters themselves ultimately are responsible for ensuring that students with disabilities receive the special education and related services and supports to which they are entitled under the law. When charters are part of another LEA, through their home district or state, the other entity is ultimately responsible for providing services to students who have disabilities. These key realities are part of the context of how funding for special education flows to public charter schools across the country.

Effect of Co substitution on Mn$_3$Ga is investigated using first-principles study for structural and magnetic properties. Without Co, ferrimagnetic Heusler compound Mn3Ga is in tetragonal phase. With Co substitution, depending on Co concentration (x) Mn$_3$Ga prefers tetragonal (cubic) phase when x \leq 0.5 (x \geq 0.5). Ferrimagnetism is robust regardless of x in both phases. While magnetic moments of two Mn do not vary significantly with x, Co magnetic moment in two phases exhibit different behaviors, leading to distinct features in total magnetic moment (M_{tot}). When x \leq 0.5, in tetragonal phase, Co magnetic moment is vanishingly small, resulting in a decrease of M_{tot} with x. In contrast, when x \geq 0.5, in cubic phase, Co magnetic moment is roughly 1$\mu_B$, which is responsible for an increase of Mtot. Electronic structure is analyzed with partial density of states for various x. To elucidate the counterintuitively small Co moment, the magnetic exchange interaction is investigated where exchange coefficient between Co and Mn is much smaller in x \leq 0.5 case than x \geq 0.5 one., Comment: 5 pages 4 figures

Inclusion starts at the top, and when the deep commitment of school and districts leaders is absent, individual teachers' efforts to create and sustain inclusive learning environments where students with disabilities can soar risk being little more than exercises in frustration. With this premise in mind, this brief shares the voices of individuals identified as "Beacons"--that is, leaders who have demonstrated a deep commitment to improving outcomes for students with disabilities. Their stories shed light onto the origins of their commitment, providing insight into how it translates into tangible actions designed to create learning environments in which all students can thrive. While some of their stories are similar, overall, their experiences document a rich and diverse pathway to inspiring leadership. [Nelson Smith assisted in writing this report. Afterword written by Lauren Morando Rhim.]

Charter schools' autonomy and flexibility provides them with the opportunity to find ways to close the performance gap between students with and without disabilities, but deep-seated, systemic challenges often cause individual charters to struggle to do so on their own. For cities with an established charter sector, a city-wide, collaborative strategy involving all stakeholders to overcome these systemic challenges is proposed. By working together, charter schools can fulfill their potential with regard to educating students with disabilities. In the wake of the COVID-19 pandemic, identifying effective strategies to accelerate learning for students with disabilities and optimize the flexibility extended to charter schools is essential. This brief introduces critical components of a strategic, city-based framework, along with details regarding how this multi-pronged approach can drive systemic and sustainable change that will lead to better access and outcomes for students with disabilities. Each component has value independently, but when combined in a coherent manner so that each augments the others, the framework has the potential to ensure that students with disabilities have access to a robust continuum of educational opportunities in districts that have widespread public school choice and, in particular, charter schools. If individual charter schools, regional government officials, authorizers, and funders work together to create a new system that spreads the responsibility, incentivizes schools to support students with disabilities, and nurtures talent to support these goals, charter schools can be agents of change for closing the gap between students with disabilities and the general education population. [This paper is the result of a collaboration with Pathway 2 Tomorrow: Local Visions for America's Future (P2T).]