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Science education inclusive of learners’ cultures requires understanding how students position scientific knowledge with regard to identity-laden beliefs, such as religions. To address this need, we developed a research tool administered across linguistic and societal contexts. In this article, we present the conceptual frameworks the instrument articulates and draws upon. We then test the construct validity and internal consistency of its dimensions based on data collected from a main sample of 238 English-speaking American, Dutch and Norwegian students, all in their final year of compulsory school education, as well as from a secondary sample of 372 French-speaking Belgian students that we use to further discuss the results from the main sample. The results obtained through exploratory and confirmatory factor analyses and by Cronbach’s alpha analysis are consistent with our theoretical model. We discuss implications for the use of this instrument by researchers, as well as formal or informal science educators.

A collective outcome or decision from a crowd often prevails over that of a single expert. Here we study this phenomenon through the lens of quantum machine learning. We compare the performance of an expert, a highly trained quantum network, to a crowd, several poorly trained ones, for quantum information processing tasks such as quantum tomography and entanglement recognition. We also show quantum-enhanced performance from a temporal crowd by using time multiplexing on a single poorly trained quantum network. Given the same resources for training, we show that the crowd outperforms the expert by a definitive margin. Ministry of Education (MOE) Published version We acknowledge the support by the Singapore Ministry of Education under its AcRF Tier 2 Grant No. T2EP50121-0006.

Energy transfer is a ubiquitous phenomenon that delivers energy from a blue-shifted emitter to a red-shifted absorber, which has enabled plentiful photonic applications of light-emitting diodes (LEDs), lasers, solar cells, and display devices1–5. The fast-emerging two-dimensional (2D) semiconductors offer unique opportunities for exploring new energy transfer mechanisms in the atomic-scale limit enabled by confined geometry and van der Waals architectures, which transcend the conventional Förster and Dexter types. Herein, we have successfully designed and constructed a planar optical microcavity-confined MoS2/hBN/WS2 heterojunction, which realizes the strong coupling among donor exciton, acceptor exciton, and cavity photon mode for the first time. Such a configuration demonstrates the unconventional energy transfer via ultrafast polariton relaxation, leading to the brightening of MoS2 neutral exciton with a record-high enhancement factor of ~ 440, i.e., two-order-of-magnitude higher than the data reported to date. A short characteristic time of ~ 1.3 ps is extracted by setting up a high-resolution k-space transient-reflectivity spectroscopy. This ultrafast polariton relaxation is attributed to the significantly enhanced intra- and inter-branch exciton-exciton scattering to overcome the hot phonon bottleneck effect, as revealed by theoretical calculation with coupled rate equations. Our study not only opens a new direction of microcavity 2D semiconductor heterojunctions for high-brightness ultrafast polaritonic light sources, but also provides a new paradigm to study the ultrafast polariton carrier dynamics.

Multiquantum-well (MQW) perovskite is one of the forerunners in high-efficiency perovskite LED (PeLEDs) research. Despite the rapid inroads, PeLEDs suffer from the pertinent issue of efficiency decrease with increasing brightness, commonly known as "efficiency roll-off". The underlying mechanisms are presently an open question. Herein, we explicate the E-field effects on the exciton states in the archetypal MQW perovskite (C6H5C2H4NH3)2PbI4, or PEPI, in a device-like architecture using field-assisted transient spectroscopy and theoretical modeling. The applied E-field results in a complex interplay of spectral blueshifts and enhancement/quenching of the different exciton modes. The former originates from the DC Stark shift, while the latter is attributed to the E-field modulation of the transfer rates between bright/dark exciton modes. Importantly, our findings uncover crucial insights into the photophysical processes under E-field modulation contributing to efficiency roll-off in MQW PeLEDs. Electrical modulation of exciton properties presents exciting possibilities for signal processing devices. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version Q.Z. is supported by the Singapore Ministry of Education under its AcRF Tier 2 Grant MOE2019-T2-2-2-066. T.K., K.D., and T.C.H.L. are supported by the AcRF Tier 2 Grant MOE2019-T2-1-004. T.C.S., S.Y., and M.F. acknowledge the support from the Singapore National Research Foundation NRF-NRFI-2018-04 and AcRF Tier 2 Grants MOE2019-T2-1-006 and MOE-T2EP50120-0004.

Parametric nonlinear optical processes are at the heart of nonlinear optics underpinning the central role in the generation of entangled photons as well as the realization of coherent optical sources. Exciton-polaritons are capable to sustain parametric scattering at extremely low threshold, offering a readily accessible platform to study bosonic fluids. Recently, two-dimensional transition-metal dichalcogenides (TMDs) have attracted great attention in strong light–matter interactions due to robust excitonic transitions and unique spin-valley degrees of freedom. However, further progress is hindered by the lack of realizations of strong nonlinear effects in TMD polaritons. Here, we demonstrate a realization of nonlinear optical parametric polaritons in a WS2 monolayer microcavity pumped at the inflection point and triggered in the ground state. We observed the formation of a phase-matched idler state and nonlinear amplification that preserves the valley population and survives up to room temperature. Our results open a new door towards the realization of the future for all-optical valley polariton nonlinear devices. Ministry of Education (MOE) Submitted/Accepted version We acknowledge the following funding sources: National Natural Science Foundation of China under grant no. 12020101003 and funding support from State Key Laboratory of Low-Dimensional Quantum Physics of Tsinghua University (Q.X.); Singapore Ministry of Education via the AcRF Tier 3 Programme ‘Geometrical Quantum Materials’ and AcRF Tier 2 project under grant nos. MOE2018-T3-1-002 and MOE2018-T2-2-068 (T.C.H.L.). Ministry of Education, University and Research of Italy via the PRIN project ‘Interacting Photons in Polariton Circuits—INPhoPOL’, FISR-COVID project ‘Wavesense’ and Joint Bilateral Agreement CNR-RFBR (Russian Foundation for Basic Research) project `Hardware implementation of a polariton neural network for neuromorphic computing`, Triennal Program 2021–2023, under grant nos. 2017P9FJBS_001 and FISR2020IP_04324 (D.S.).