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The scaling of Si transistor technology has resulted in a remarkable improvement in the performance of integrated circuits over the last decades. However, scaled transistors also require reduced electrical interconnect dimensions, which lead to greater losses and power dissipation at circuit level. This is mainly caused by enhanced surface scattering of charge carriers in copper interconnect wires at dimensions below 30 nm. A promising approach to mitigate this issue is to use directional conductors, i.e. materials with anisotropic Fermi surface, where proper alignment of crystalline orientation and transport direction can minimize surface scattering. In this work, we perform a resistivity scaling study of the anisotropic semimetal NbP as a function of crystalline orientation. We use here focused ion beam to pattern and scale down NbP crystallites to dimensions comparable to the electron scattering length at cryogenic temperatures. The experimental transport properties are correlated with the Fermi surface characteristics through a theoretical model, thus identifying the physical mechanisms that influence the resistivity scaling of anisotropic conductors. Our methodology provides an effective approach for early evaluation of anisotropic materials as future ultra-scalable interconnects, even when they are unavailable as epitaxial films., Comment: 18 pages, 3 figures

When a charged particle is subject to both a periodic potential and magnetic field, oscillations in its conductivity occur when the field-induced cyclotron radius is commensurate with the period of the potential. This effect has been observed in two-dimensional systems including electron gases and graphene, and is related to the Hofstadter spectrum of magnetic minibands. Here we show that commensuration oscillations also can arise in the ballistic transport regime of a nanostructured 3D material, with the Weyl semimetal NbP. These oscillations encode information about the quasiparticles at the Fermi-surface, including their momentum, charge, mass, and rotational symmetry. In particular, we use the magnetic field and temperature dependence of the commensuration oscillations to extract the Fermi-momenta and quasiparticle mass, in good agreement with Shubnikov-de Haas quantum oscillations. Furthermore, we investigate the relationship between the engineered superlattice symmetry and resistivity response based on the symmetry of the Fermi surface and charge of the quasiparticles. These results demonstrate how nanopatterned superlattices can be used to characterize a 3D materials' fermiology, and also point towards new ways of engineering quantum transport in these systems., Comment: 25 Pages, 4 main figures, 4 supplementary figures

The chiral anomaly, a hallmark of chiral spin-1/2 Weyl fermions, is an imbalance between left- and right-moving particles that underpins both high and low energy phenomena, including particle decay and negative longitudinal magnetoresistance in Weyl semimetals. The discovery that chiral crystals can host higher-spin generalizations of Weyl quasiparticles without high-energy counterparts, known as multifold fermions, raises the fundamental question of whether the chiral anomaly is a more general phenomenon. Answering this question requires materials with chiral quasiparticles within a sizable energy window around the Fermi level, that are unaffected by trivial extrinsic effects such as current jetting. Here we report the chiral anomaly of multifold fermions in CoSi, which features multifold bands within about 0.85 eV around the Fermi level. By excluding current jetting through the squeezing test, we measure an intrinsic, longitudinal negative magnetoresistance. We develop the semiclassical theory of magnetotransport of multifold fermions that shows that the negative magnetoresistance originates in their chiral anomaly, despite a sizable and detrimental orbital magnetic moment contribution, previously unaccounted for. A concomitant nonlinear Hall effect supports the multifold-fermion origin of magnetotransport. Our work confirms the chiral anomaly of higher-spin generalizations of Weyl fermions, currently inaccessible outside the solid-state.

This primer summarizes the Education Sciences Reform Act (ESRA), the Educational Technical Assistance Act (ETAA), and the National Assessment of Educational Progress Authorization Act (NAEPAA). The report is organized in a manner that aligns with P.L. 107-279, the law that enacted the three acts. The ESRA authorizes much of the federal government's efforts to collect statistics and conduct research on the U.S. educational system. Part A of the ESRA establishes the Institute of Education Sciences (IES) as an independent research institute and the National Board of Educational Sciences to advise and approve priorities for data collection and research. Parts B thru E of the ESRA authorize four National Education Centers that carry out the research and data collection duties of IES. The ETAA authorizes support for technical assistance activities and the development of state systems that integrate student-level data from preschool through postsecondary education and employment. The NAEPAA authorizes support for assessments of the academic achievement of students across the United States. Although authorities in the acts expired in FY2008, funding has continued through annual appropriations legislation. In FY2023, $734 million was appropriated to support IES' activities.

The topology of the Fermi surface significantly influences the transport properties of a material. Firstly measured through quantum oscillation experiments, the Fermi surfaces of crystals are now commonly characterized using angle-resolved photoemission spectroscopy (ARPES), given the larger information volume it provides. In the case of Weyl semimetals, ARPES has proven remarkably successful in verifying the existence of the Weyl points and the Fermi arcs, which define a Weyl Fermi surface. However, ARPES is limited in resolution, leading to significant uncertainty when measuring relevant features such as the distance between the Weyl points. While quantum oscillation measurements offer higher resolution, they do not reveal insights into the cross-sectional shape of a Fermi surface. Moreover, both techniques lack critical information about transport, like the carriers mean free path. Here, we report measurements unveiling the distinctive peanut-shaped cross-section of the Fermi surface of Weyl fermions and accurately determine the separation between Weyl points in the Weyl semimetal NbP. To surpass the resolution of ARPES, we combine quantum oscillation measurements with transverse electron focusing (TEF) experiments, conducted on microstructured single-crystals. The TEF spectrum relates to the Fermi surface shape, while the frequency of the quantum oscillations to its area. Together, these techniques offer complementary information, enabling the reconstruction of the distinctive Weyl Fermi surface geometry. Concurrently, we extract the electrical transport properties of the bulk Weyl fermions. Our work showcases the integration of quantum oscillations and transverse electron focusing in a singular experiment, allowing for the measurements of complex Fermi surface geometries in high-mobility quantum materials.

Income-driven repayment (IDR) plans are a subset of student loan repayment plans that cap a borrower's monthly payment at a percentage of their discretionary income, which is defined as a portion of a borrower's adjusted gross income (AGI) that exceeds a specified multiple of the federal poverty line (FPL) for the borrower's family size. A borrower may be in negative amortization under an IDR plan, which means that their monthly payment can be less than the interest that accrues in a given month, and the accumulation of unpaid interest may lead to an increase in their loan balance. Any loan balance that remains outstanding after the borrower has made qualifying payments according to an IDR plan for a maximum repayment period is to be forgiven. Over the last nearly 30 years, Congress and the Department of Education (ED) have created the following existing IDR plans: the Income-Contingent Repayment (ICR) plan, two Income-Based Repayment (IBR) plans, the Pay As You Earn (PAYE) repayment plan, and the Revised Pay As You Earn (REPAYE) repayment plan. In January 2023, ED published a Notice of Proposed Rulemaking (NPRM) to make a number of substantial amendments to the federal student loan IDR plans. This report discusses the most frequently asked questions related to the proposed rules in the following areas: (1) background on IDR plans; (2) changes specific to the REPAYE repayment plan such as to borrower eligibility, monthly payments, interest benefits, and the maximum repayment period; (3) changes applicable to all IDR plans; other provisions related to delinquent and defaulted borrowers; and (4) the estimated cost of the proposed rules.

Outstanding federal student loan debt exceeds $1.6 trillion and is owed by approximately 45 million borrowers. Thus, a policy to broadly cancel federal student loan debt would directly apply to a discrete segment of the U.S. population. Cancelling some amount of federal student loan debt would alleviate loan repayment burdens for qualifying borrowers, but depending on the policy design and individual borrower circumstances, borrowers may experience different levels of relief, possibly resulting in different effects on their personal finances. Broad-based student loan cancellation would have significant implications for the federal budget. A primary determinant of the cost to the government would be the total amount of student loan debt to be cancelled. Other cost determinants would include how the loan cancellation policy was to be effectuated, associated administrative costs, and borrower behavior. Cancelling federal student loan debt may have implications for the federal student loan system. Loan cancellation, particularly a one-time cancellation effort, might not address underlying issues relating to unmanageable amounts of student loan debt. Some recent research suggests that policies to provide across-the-board loan cancellation may result in higher-income households receiving a higher share of loan cancellation benefits than lower-income households in terms of total dollar amounts cancelled and savings in annual debt service payments. Other research, examining potential effects on wealth inequality, shows mixed evidence on the potential effects of student loan cancellation. Some original analyses presented in this report to complement existing research focus on longitudinal data from a 12-year follow up on the cohort of borrowers who started postsecondary education in academic year 2003-2004. These analyses suggest that certain groups of borrowers (Black, American Indian, and lower income Title IV student loan borrowers) have made less progress in paying down the original principal amount of their student loan debt when compared with borrowers of other races or ethnicities or household income levels. Among other findings, these analyses also suggest that individuals who borrowed larger amounts were less likely to have made progress in paying down the original principal amount borrowed than borrowers with lower principal amounts. These analyses also suggest that while 26% of borrowers had no remaining loan balance, among those with outstanding loans a large share (60%) had an outstanding balance greater than 90% of the original amount borrowed.

In this paper, we provide a system level perspective on the design of control electronics for large scale quantum systems. Quantum computing systems with high-fidelity control and readout, coherent coupling, calibrated gates, and reconfigurable circuits with low error rates are expected to have superior quantum volumes. Cryogenic CMOS plays a crucial role in the realization of scalable quantum computers, by minimizing the feature size, lowering the cost, power consumption, and implementing low latency error correction. Our approach toward achieving scalable feed-back based control systems includes the design of memory based arbitrary waveform generators (AWG's), wide band radio frequency analog to digital converters, integrated amplifier chain, and state discriminators that can be synchronized with gate sequences. Digitally assisted designs, when implemented in an advanced CMOS node such as 7 nm can reap the benefits of low power due to scaling. A qubit readout chain demands several amplification stages before the digitizer. We propose the co-integration of our in-house developed InP HEMT LNAs with CMOS LNA stages to achieve the required gain at the digitizer input with minimal area. Our approach using high impedance matching between the HEMT LNA and the cryogenic CMOS receiver can relax the design constraints of an inverter-based CMOS LNA, paving the way toward a fully integrated qubit readout chain. The qubit state discriminator consists of a digital signal processor that computes the qubit state from the digitizer output and a pre-determined threshold. The proposed system realizes feedback-based optimal control for error mitigation and reduction of the required data rate through the serial interface to room temperature electronics.

Realization of qubit gate sequences require coherent microwave control pulses with programmable amplitude, duration, spacing and phase. We propose an SRAM based arbitrary waveform generator for cryogenic control of spin qubits. We demonstrate in this work, the cryogenic operation of a fully programmable radio frequency arbitrary waveform generator in 14 nm FinFET technology. The waveform sequence from a control processor can be stored in an SRAM memory array, which can be programmed in real time. The waveform pattern is converted to microwave pulses by a source-series-terminated digital to analog converter. The chip is operational at 4 K, capable of generating an arbitrary envelope shape at the desired carrier frequency. Total power consumption of the AWG is 40-140mW at 4 K, depending upon the baud rate. A wide signal band of 1-17 GHz is measured at 4 K, while multiple qubit control can be achieved using frequency division multiplexing at an average spurious free dynamic range of 40 dB. This work paves the way to optimal qubit control and closed loop feedback control, which is necessary to achieve low latency error mitigation, Comment: 4 pages, IEEE ESSCIRC 2022 conference

In response to the COVID-19 pandemic, most elementary and secondary schools and local educational agencies (LEAs) across the United States stopped offering in-person instruction in February or March 2020. By the middle of April 2020, 48 states, four U.S. territories, the District of Columbia, and the Department of Defense Education Activity ordered or recommended school building closures for the rest of their academic year, affecting at least 50.8 million public school students. Congress has expressed interest in the impact of the pandemic on elementary and secondary schools, especially states' and LEAs' ability to successfully transition to remote learning, as well as the extent to which schools have implemented returns to in-person learning. This report focuses on online learning in elementary and secondary schools during the COVID-19 pandemic and on the most emergent issues associated with the implementation of online learning on a mass scale that took place at the start of the pandemic in spring 2020. It also describes the issues faced by school districts as they consider approaches for providing instruction in the 2021-2022 school year. Finally, it delineates federal efforts to provide assistance to support states and localities dealing with these issues.

October 16, 2024 Contents Introduction Title I: Transparency Part A: Definitions Section 101: Definitions Part B: College Costs and Financial Value Section 111: Financial Aid Offers Section 112: College Scorecard [...]

October 9, 2024 Federal financial assistance for students pursuing postsecondary education is primarily provided through Title IV of the Higher Education Act (HEA). The general intent for such aid is […]

The Teacher Education Assistance for College and Higher Education (TEACH) Grant program was established in 2007 to support students pursuing teaching certifications, particularly in low-income schools. Recipients can receive up to $4,000 annually, but must fulfill teaching service obligations or risk their grants being converted into loans. Over 400,000 grants totaling $1.3 billion have been disbursed since the program's inception, with ongoing discussions about potential changes to address program challenges and improve effectiveness. Recent adjustments have shifted some administrative responsibilities to recipients, allowing for more direct management of participation in TEACH Grants through StudentAid.gov. [Extracted from the article]

Updated December 2, 2022 After years of increasing, growth in counts of federal student loan borrowers, average annual amounts borrowed, and average cumulative debt owed appears to be moderating somewhat. [...]

Updated July 8, 2020 President Donald J. Trump declared a U.S. national emergency on March 13, 2020, in response to the COVID-19 pandemic. The Coronavirus Aid, Relief, and Economic Security [...]