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The evolution of science education is a dynamic process driven by advances in pedagogy, technology, and especially, our understanding of how students learn. Educators are exploring innovative teaching and learning methodologies such as active learning, incorporated technology, interdisciplinary approach, flipped classrooms, personalized teaching, and many more. The goal of all these evolving methodologies is to empower students with not only a strong foundation in scientific knowledge but also with the skills and mindset required to thrive in the future world. By adopting these innovative approaches, educators can help students become effective problem solvers, critical thinkers, and life learning citizens. Our focus is redesigning individual student learning activities into group learning activities that will benefit various ways of education by building each others support, connection, and communication. Unloading individual homework and loading in-class group work during a synchronous classroom setting will benefit all levels of learnings effectively. Assigning most of the classwork to be completed during class time has potential benefits since students are more likely to be engaged and focused individually and jointly by sharing and communicating subject matter effectively. We are discussing how to facilitate the group work effectively by creating group assignments for personalized classrooms, setting specific rules and class ethics to follow for the best learning practice, imposing a list of roles to each group member, introducing a list of ground rules related to justice, equity, and diversity inclusion (JDEI) within the group. The students performances, progress and effectiveness are analyzed and compared., Comment: 7 pages, 4 figures, 1 table

The recent development of science education leads educators to explore new teaching and learning methodologies and restructure classes and assignments to bring students' knowledge to the highest level of education by allowing learners to gain various skills that are reflected in their future. We are discussing how to develop and deliver effective online courses by personalizing the class and individualizing the assignments for learners to succeed in Physics. Various teaching and learning activities are aimed at effective learning and interaction to enhance student learning in this class structure. The students' performances and progress are analyzed in four large introductory Physics classes. Student registration and retention are well preserved by providing learners freedom of education, a sense of belonging, mindset-growing encouragements, effective feedback, problem-solving strategies, and one-to-one communications. Academic integrity is well-balanced by individualizing the assignments, personalizing class materials, breaking down problems, and investigating ChatGPT usage. The students' performances are analyzed by evaluating class performance in total grade distribution, missing assignments, and choice-based learning. Student progress is investigated by analyzing their commitment, respect, willingness to improve, and time management toward education. Overall, the class model demonstrates great performance, progress, and achievements that indicate a positive learning environment for all students throughout the semester. Hence, the effective model with personalized assignments, and other strategies that we share will be highly beneficial for science education., Comment: 12 pages, 10 figures

Student performance of virtual introductory physics class (calculus-based mechanics) is analyzed. A fully web-enhanced class was done synchronously. The analysis is done in two categories, averaging all mid-exams (or chapter exams) and cumulative final exams. It shows that students perform well with shorter timed mid-semester assessments (or chapter exams) than the longer timed assessments. Results were then compared with two survey questions to investigate the effect of the background knowledge of physics and calculus on their performance. It shows two interesting results, a) students with basic conceptual background knowledge of physics perform well, b) calculus knowledge does not correlate well with student performance. These findings can be used to rethink and redesign the assessments for calculus-based introductory physics classes. Also, the findings can be used to develop a supplemental support program to enhance student performance., Comment: 7 pages, 3 figures

This is the third series of the lab manuals for virtual teaching of introductory physics classes. This covers fluids, waves, thermodynamics, optics, interference, photoelectric effect, atomic spectra, and radiation concepts. A few of these labs can be used within Physics I and a few other labs within Physics II depending on the syllabi of Physics I and II classes. Virtual experiments in this lab manual and our previous Physics I (arXiv.2012.09151) and Physics II (arXiv.2012.13278) lab manuals were designed for 2.45 hrs long lab classes (algebra-based and calculus-based). However, all the virtual labs in these three series can be easily simplified to align with conceptual type or short time physics lab classes as desired. All the virtual experiments were based on open education resource (OER) type simulations. Virtual experiments were designed to simulate in-person physical laboratory experiments. Student learning outcomes (understand, apply, analyze and evaluate) were studied with detailed lab reports per each experiment and end of the semester written exam which was based on experiments. Special emphasis was given to study the student skill development of computational data analysis., Comment: 82 pages, 38 figures and 56 tables

Introductory electricity and magnetism lab manual was designed to use with virtual Physics II class. The lab manual consists of experiments on electrostatics, electric potential and energy, current and resistance, DC circuits, electromagnetism, and AC circuits. Virtual experiments were based on simulations. Open educational resources (OER) were used for all experiments. Virtual experiments were designed to simulate in-person physical lab experiments. Special emphasis was given to computational data analysis with excel. Formatted excel sheets per each lab were given to students and step by step calculation in excel were explained during the synchronous class. Learning management system (LMS) was used to fully web enhance the lab class. Virtual labs were delivered by using live video conference technology and recorded lab sessions were added to LMS. Lab class were tested with both virtual delivery methods (synchronous and asynchronous). Student learning outcomes (understand, apply, analyze and evaluate) were studied with detailed lab reports and end of the semester lab-based written exam which confirmed the virtual lab class was as effective as the in-person physical lab class., Comment: 68 pages

A set of virtual experiments were designed to use with introductory physics I (analytical and general) class, which covers kinematics, Newton laws, energy, momentum, and rotational dynamics. Virtual experiments were based on video analysis and simulations. Only open educational resources (OER) were used for experiments. Virtual experiments were designed to simulate in-person physical laboratory experiments. All the calculations and data analysis (analytical and graphical) were done with Microsoft excel. Formatted excel tables were given to students and step by step calculations with excel were done during the class. Specific emphasis was given to student learning outcomes such as understand, apply, analyze and evaluate. Student learning outcomes were studied with detailed lab reports per each experiment and end of the semester written exam (which based on experiments). Lab class was fully web-enhanced and managed by using a Learning management system (LMS). Every lab class was recorded and added to the LMS. Virtual labs were done by using live video conference technology and labs were tested with the both synchronous and asynchronous type of remote teaching methods., Comment: 82 pages

The electronic properties of the heavy metal superconductor LaIr3 are reported. The estimated superconducting parameters obtained from physical properties measurements indicate that LaIr3 is a BCS-type superconductor. Electronic band structure calculations show that Ir d- states dominate the Fermi level. A comparison of electronic band structures of LaIr3 and LaRh3 shows that the Ir-compound has a strong spin-orbit-coupling effect, which creates a complex Fermi surface., Comment: 6 pages and 5 figures

We report a reinvestigation of superconducting Sn$_{1-x}$In$_{x}$Te at both low and high In doping levels. Analysis of the superconductivity reveals a fundamental change as a function of \textit{x}: the system evolves from a weakly coupled to a strongly coupled superconductor with increasing indium content. Hall Effect measurements further show that the carrier density does not vary linearly with Indium content; indeed at high Indium content, the samples are overall \textit{n}-type, which is contrary to expectations of the standard picture of In$^{1+}$ replacing Sn$^{2+}$ in this material. Density functional theory calculations probing the electronic state of In in SnTe show that it does not act as a trivial hole dopant, but instead forms a distinct, partly filled In 5\textit{s} - Te 5\textit{p} hybridized state centered around E$_F$, very different from what is seen for other nominal hole dopants such as Na, Ag, and vacant Sn sites. We conclude that superconducting In-doped SnTe therefore cannot be considered as a simple hole doped semiconductor., Comment: 12 pages and 7 figures

We report the electronic properties of the cubic laves phase superconductor CaIr2 (Tc = 5.8 K), in which the Ir atoms have a Pyrochlore lattice. The estimated superconducting parameters obtained from magnetization and specific heat measurements indicate that CaIr2 is a weakly coupled BCS superconductor. Electronic band structure calculations show that the Ir d-states are dominant at the Fermi level, creating a complex Fermi surface that is impacted substantially by spin orbit coupling., Comment: 6 pages, 4 figs and 1 table. arXiv admin note: text overlap with arXiv:1406.2956

Based on the interplay of theory and experiment, a large new family of filled group 9 (Co, Rh and Ir) skutterudites is designed and synthesized. The new materials fill the empty cages in the structures of the known binary CoSb3, RhSb3 and IrSb3 skutterudites with alkaline, alkaline earth, and rare earth atoms to create compounds of the type AyB4X12; A atoms fill the cages to a fraction y, B are the group 9 transition metals, and X is a mixture of electronegative main group elements chosen to achieve chemical stability by adjusting the electron counts to electron-precise values. Forty-three new compounds are reported, antimony-tin and phosphorous-silicon based, with 63 compositional variations presented. The new family of compounds is large and general. The results described here can be extended to the synthesis of hundreds of new group 9 filled skutterudites., Comment: A revised version with the title"A large family of filled skutterudites stabilized by electron count"will appear in Nature Communications

3D Dirac semi-metals (DSMs) are materials that have massless Dirac electrons and exhibit exotic physical properties It has been suggested that structurally distorting a DSM can create a Topological Insulator (TI), but this has not yet been experimentally verified. Furthermore, quasiparticle excitations known as Majorana Fermions have been theoretically proposed to exist in materials that exhibit superconductivity and topological surface states. Here we show that the cubic Laves phase Au$_2$Pb has a bulk Dirac cone above 100 K that gaps out upon cooling at a structural phase transition to create a topologically non trivial phase that superconducts below 1.2 K. The nontrivial Z$_2$ = -1 invariant in the low temperature phase indicates that Au$_2$Pb in its superconducting state must have topological surface states. These characteristics make Au$_2$Pb a unique platform for studying the transition between bulk Dirac electrons and topological surface states as well as studying the interaction of superconductivity with topological surface states.

We report the superconducting properties of single crystals of the intermetallic perovskite-related compound BaBi$_{3}$. The superconducting transition temperature ($T_{c}=5.82$~K) was obtained from heat capacity measurements. Using the measured values for the critical fields $H_{c1}, H_{c2}$, and the specific heat $C$, we estimate the thermodynamic critical field $H_{c}$(0), coherence length $\xi$(0), Debye temperature $\Theta _{D}$ and coupling constant $\lambda _{ep}$. $\Delta C/\gamma T_{c}$ and $\lambda _{ep}$ suggest that BaBi$_{3}$ is a moderately coupled superconductor and $\gamma $ suggests an enhanced density of states at the Fermi level. Electronic band structure calculations show a complex Fermi surface and a moderately high DOS at the Fermi level. Further analysis of the electronic specific heat shows that the superconducting properties are dominated by s-wave gap., Comment: 6 pages, 4 figures, 1 table. arXiv admin note: text overlap with arXiv:1402.4440

Magnetoresistance is the change of a material's electrical resistance in response to an applied magnetic field. In addition to its intrinsic scientific interest, it is a technologically important property, placing it in "Pasteur's quadrant" of research value: materials with large magnetorsistance have found use as magnetic sensors 1, in magnetic memory 2, hard drives 3, transistors 4, and are the subject of frequent study in the field of spintronics 5, 6. Here we report the observation of an extremely large one-dimensional positive magnetoresistance (XMR) in the layered transition metal dichalcogenide (TMD) WTe2; 452,700 percent at 4.5 Kelvin in a magnetic field of 14.7 Tesla, and 2.5 million percent at 0.4 Kelvin in 45 Tesla, with no saturation. The XMR is highly anisotropic, maximized in the crystallographic direction where small pockets of holes and electrons are found in the electronic structure. The determination of the origin of this effect and the fabrication of nanostructures and devices based on the XMR of WTe2 will represent a significant new direction in the study and uses of magnetoresistivity. *The published version of the paper includes co-authors Tian Liang and Max Hirschberger. **This paper has been published with new MR data to 60T where the MR of WTe2 reaches 13 million percent (at 0.5K) and still shows no signs of saturation. We also have new electron diffraction patterns to lower temperature (10K). We discuss the possible origin of the MR as coming from an electron-hole 'resonance' condition established by a perfect n/p ratio of 1 (more details in a new "extended data" section). This makes WTe2, possibly, the first realization of a perfectly balanced semimetal. ***The paper is published as "Large non-saturating magnetoresistance in WTe2" in Nature (2014), DOI:10.1038/nature13763, Comment: Nature, 2014

We report the superconducting properties of the K$_{x}$WO$_{3}$ tetragonal tungsten bronze. The highest superconducting transition temperature ($T_{c}=2.1$K) was obtained for K$_{0.38}$WO$_{3}$. $T_{c}$ decreases linearly with increasing K content. Using the measured values for the upper critical field $H_{c2}$, and the specific heat $C$, we estimate the orbital critical field $H_{c2}$(0), coherence length $\xi$(0), Debye temperature $\Theta _{D}$ and coupling constant $\lambda _{ep}$. The magnitude of the specific heat jump at $T_{c}$ suggests that the K$_{x}$WO$_{3}$ tetragonal tungsten bronze is a weakly-coupled superconductor. The superconducting phase diagram of the doped tungsten bronze family is presented., Comment: 7 Pages, 6 figures and 1 Table

We report the synthesis and measurements of magnetic, transport, and thermal properties of polycrystalline Nb0.18Re0.82, which has a superconducting transition at Tc ~ 8.8 K. The non-centrosymmetric alpha-Mn structure of the compound is confirmed by X-ray diffraction. Using the measured values for the lower critical field Hc1, upper critical field Hc2, and the specific heat C, we estimate the thermodynamic critical field Hc(0), coherence length {\xi}(0), penetration depth {\lambda}(0), and the Ginzburg-Landau parameter {\kappa}(0). The specific heat jump at Tc, {\Delta}C/{\gamma}Tc = 1.86, suggests that Nb0.18Re0.82 is moderately coupled superconductor. Below Tc the electronic specific heat decays exponentially, suggesting that the gap is isotropic. Our data suggests that the triplet admixture is weak in the polycrystalline form of compound. However, the estimated value of the upper critical field Hc2(0) is close to the calculated Pauli limit indicating the need for single crystal measurements., Comment: 15 pages, 8 figures, submitted to Physical Review B