Learning practices through recursive questionnaires

Distance education or distance learning (DL) in undergraduate courses is growing considerably in the last decades (Holmes & Reid, 2017) and got even more attention due to the COVID pandemic (Crawford et al., 2020; Baggaley, 2020). Students pursuing distance learning have often suffered from isolation and lack of a learning community, resulting in high dropout rates. In general, students’ engagement depends strongly on the evaluation methods (Holmes, 2018), and they define how students manage their time in study. Introduction to Physical Sciences 1 (ICF1) is the subject in which this work was developed in a DL course with over 1500 students per semester at CEDERJ (Distance Education Center of the State of Rio de Janeiro). In this work, we modified the method of evaluation of two optional assessments (OA) that was given to the students, whose main goal is to promote the practice, through exercises, of two fundamental contents in physics which students often have doubts and misconceptions from high school: vectors (OA1) and Newton's laws (OA2). This modification was carried out by implementing a recursive formative online assessment that students can answer as many times as they want until a specified due date. The assessment avoids memorizing the answers to the questions by generating new numerical values for each question and randomly mixing their order in every new attempt. After finishing the questionnaire, students receive immediate feedback to correct their mistakes and try to achieve a better score, in such a way that mistakes can be beneficially used as part of their learning process. Each attempt is recorded and all students’ progress is analyzed using a computational Python code. With this approach, the professor can identify and eventually interact with students who need a higher level of attention before the final exams. The former OAs were not clearly evaluating the students and helping them to better understand the required subjects. In the old format, comparisons and copying of questions could be used by the students in such a way that created an illusory impression on them that they were understanding the underlying concepts. Thus, there was a lack of correlation between the scores in the OAs and the final scores of the students. Our analysis after the implementation of the recursive questionnaires, shows that students with high scores in the OA have more chances to pass the course, as expected from an exam that correctly evaluates the students’ performance. This methodology is a valuable asset for the students’ learning process, regardless of whether they are in a DL course or a regular face-to-face course, and for the professors to identify patterns that can foresee students’ difficulties with their learning progress, allowing to address specific students in need even in classes with a large number of students. REFERENCES Baggaley, J. (2020). Educational distancing. Distance Education, 41(4), 582-588. https://doi.org/10.1080/01587919.2020.1821609 Crawford, J., Butler-Henderson, K., Rudolph, J., Malkawi, B., Glowatz, M., Burton, R., Magni, P., & Lam, S. (2020). COVID-19: 20 countries' higher education intra-period digital pedagogy responses. Journal of Applied Learning & Teaching, 3(1), 1-20. http://dx.doi.org/10.37074/jalt.2020.3.1.7 Holmes, C. M. & Reid, C. (2017). A comparison study of on-campus and online learning outcomes for a research methods course. The Journal of Counselor Preparation and Supervision, 9(2), 15. http://dx.doi.org/ 10.7729/92.1182 Holmes, N. (2018). Engaging with assessment: Increasing student engagement through continuous assessment. Active Learning in Higher Education, 19(1), 23-34. https://doi.org/10.1177/146978741772323

Voltage-tunable dual-colour quantum Bragg mirror detector (QBMD)

The electronic quasi-bound state in the continuum concept is explored in an InGaAs/InAlAs heterostructure to create a voltage-tunable dual-colour quantum Bragg mirror detector. This heterostructure is based on one main quantum well embedded between two different superlattices. By bandgap engineering, each superlattice gives rise to quasi-bound states in the continuum with a preferential direction for electron extraction. Due to these states, the photovoltaic photocurrent presents a dual-colour response, one in a positive direction at 340 meV (3.6 µm), and one in a negative direction at 430 meV (2.9 µm). The simultaneous dual-colour detection can be switched to a single-colour detection (340 meV or 430 meV) by applying a bias voltage. At 77 K, the specific detectivity for simultaneous dual-colour is 2.5·10⁸ Jones, while the single-colour detectivities are 2.6·10⁹ Jones at +2.0 V and 7.7·10⁸ Jones at -1.6 V for 340 meV and 430 meV, respectively

Exploring parity anomaly for dual peak infrared photodetection

In this paper, we show a superlattice quantum well infrared photodetector (S-QWIP) grown by metal-organic vapor phase epitaxy with two narrow photocurrent peaks in the mid infrared range due to transitions between the ground state from a quantum well and5212CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPERJ - FUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIROCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMsem informaçãosem informaçãosem informaçãosem informaçã

Progress in symmetric and asymmetric superlattice quantum well infrared photodetectors

Herein, two challenges are addressed, which quantum well infrared photodetectors (QWIPs), based on III-V semiconductors, face, namely: photodetection within the so-called "forbidden gap", between 1.7 and 2.5 microns, and room temperature operation using thermal sources. First, to reach this forbidden wavelength range, a QWIP which consists of a superlattice structure with a central quantum well (QW) with a different thickness is presented. The different QW in the symmetric structure, which plays the role of a defect in the otherwise periodic structure, gives rise to localized states in the continuum. The proposed InGaAs/InAlAs superlattice QWIP detects radiation around 2.1 microns, beyond the materials bandoffset. Additionally, the wavefunction parity anomaly is explored to increase the oscillator strength of the optical transitions involving higher order states. Second, with the purpose of achieving room temperature operation, an asymmetric InGaAs/InAlAs superlattice, in which the QW with a different thickness is not in the center, is used to detect infrared radiation around 4 microns at 300 K. This structure operates in the photovoltaic mode because it gives rise to states in the continuum which are localized in one direction and extended in the other, leading to a preferential direction for current flow531634th International Conference on the Physics of Semiconductors (ICPS)FAPERJ - Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeir