Annals of Quantum and Condensed Matter Physics - Articles
Browse published articles from Annals of Quantum and Condensed Matter Physics
Lemaire, A., Aaltonen, S., Bauer, F., Ndlovu, T., Ivanova, T., Ivanova, V., Okeke, T., Lemaire, M.
Cyberbullying has become a major concern in the digital world, with social media platforms facilitating harmful interactions that target individuals. Although there has been significant research, studies specifically focusing on Bengali cyberbullying remain scarce. This paper addresses this gap by analyzing over 70,000 social media comments in the Bengali language. The dataset is preprocessed for sentiment analysis to classify positive and negative comments, followed by topic modeling for negative comments using Latent Dirichlet Allocation (LDA) to extract features from age, gender, ethnicity, religion-based, and miscellaneous comments. Various models are applied, including Support Vector Machine, XGBoost, CNN+BiLSTM+GRU, mBERT, XLM-R, etc. Among the evaluated models, mBERT demonstrated the highest performance, attaining an accuracy of 92%. While the CNN+BiLSTM+GRU hybrid model outperformed with an accuracy of 91%. Further improvements are done by incorporating BERT embeddings into CNN and ANN models, and achieved an accuracy of 93%. To enhance model transparency and trust, Local Interpretable Model-agnostic Explanations is applied to interpret predictions.
Revisiting: Bengali cyberbullying detection: A comprehensive dataset for advanced analysis
Lemaire, A., Aaltonen, S., Bauer, F., Ndlovu, T., Ivanova, T., Ivanova, V., Okeke, T., Lemaire, M.
Cyberbullying has become a major concern in the digital world, with social media platforms facilitating harmful interactions that target individuals. Although there has been significant research, studies specifically focusing on Bengali cyberbullying remain scarce. This paper addresses this gap by analyzing over 70,000 social media comments in the Bengali language. The dataset is preprocessed for sentiment analysis to classify positive and negative comments, followed by topic modeling for negative comments using Latent Dirichlet Allocation (LDA) to extract features from age, gender, ethnicity, religion-based, and miscellaneous comments. Various models are applied, including Support Vector Machine, XGBoost, CNN+BiLSTM+GRU, mBERT, XLM-R, etc. Among the evaluated models, mBERT demonstrated the highest performance, attaining an accuracy of 92%. While the CNN+BiLSTM+GRU hybrid model outperformed with an accuracy of 91%. Further improvements are done by incorporating BERT embeddings into CNN and ANN models, and achieved an accuracy of 93%. To enhance model transparency and trust, Local Interpretable Model-agnostic Explanations is applied to interpret predictions.
Laurent, O., Johansson, F.
Objective . Radiation therapy at ultra-high dose rate (UHDR) has emerged in the past decade as a novel technique with potential to improve the therapeutic index through a phenomenon referred to as ‘FLASH effect’. Its reliable pre-clinical studies and safe clinical deployment would benefit from dosimeters with high spatiotemporal resolution, ideally with capability to perform pulse-by-pulse dosimetry for pulsed beams. Scintillation imaging has shown potential for high spatiotemporal resolution dosimetry that may be well-suited for UHDR beams. Our aim is to develop an ultra-high resolution scintillation imaging dosimetry system for characterization of pulsed UHDR proton beams on a pulse-by-pulse basis. Approach. A gantry-mounted proton therapy synchrocyclotron was used to deliver UHDR beams at ∼90 Gy s −1 average dose rate. A BC-408 plastic scintillator block (30 × 30 × 5 cm 3 ), facing a high-speed camera inside an optically sealed housing, was used for range, relative dose-per-pulse, vertical spot position, Bragg peak (BP) widths, and beam size measurements. Another BC-408 plastic scintillator block (30 × 30 × 0.5 cm 3 ), facing a mirror at 45°, was used to measure the spots’ lateral size and position. A high-speed complementary metal–oxide–semiconductor camera system, temporally gated with the accelerator’s pulse train, was used for imaging. Series of proton pulses with different ranges were delivered at various dose rates per pulse while the corresponding scintillation images were recorded to extract various beam parameters. Results. Individual image frames corresponding to each delivered pulse were successfully obtained at ∼0.08 mm per-pixel resolution. The integrated image intensity at the BP showed a linear correlation with the delivered charge-per-pulse. The scintillation signal agreed with the charge reading from the transmission ionization chamber within 1%. Our measurements did not demonstrate appreciable dose rate dependency of the ionization quenching in the scintillator. Range measurements on a pulse-by-pulse basis agreed within 1 mm of the programmed range and were confirmed with a multi-layer ionization chamber device. Spot sizes were measured within 0.3 mm of the expected values. Significance. Synchronized scintillation imaging can provide ultra-high spatiotemporal resolution dosimetry of pulsed UHDR proton beams desired for beam characterization. A strong correlation between measured scintillation intensity and beam current suggests that our system can be expanded for quantitative multidimensional dosimetry.
Further evidence: Pulse-by-pulse ultra-high resolution scintillation imaging of proton FLASH beams produced by a gantry-mounted synchrocyclotron
Laurent, O., Johansson, F.
Objective . Radiation therapy at ultra-high dose rate (UHDR) has emerged in the past decade as a novel technique with potential to improve the therapeutic index through a phenomenon referred to as ‘FLASH effect’. Its reliable pre-clinical studies and safe clinical deployment would benefit from dosimeters with high spatiotemporal resolution, ideally with capability to perform pulse-by-pulse dosimetry for pulsed beams. Scintillation imaging has shown potential for high spatiotemporal resolution dosimetry that may be well-suited for UHDR beams. Our aim is to develop an ultra-high resolution scintillation imaging dosimetry system for characterization of pulsed UHDR proton beams on a pulse-by-pulse basis. Approach. A gantry-mounted proton therapy synchrocyclotron was used to deliver UHDR beams at ∼90 Gy s −1 average dose rate. A BC-408 plastic scintillator block (30 × 30 × 5 cm 3 ), facing a high-speed camera inside an optically sealed housing, was used for range, relative dose-per-pulse, vertical spot position, Bragg peak (BP) widths, and beam size measurements. Another BC-408 plastic scintillator block (30 × 30 × 0.5 cm 3 ), facing a mirror at 45°, was used to measure the spots’ lateral size and position. A high-speed complementary metal–oxide–semiconductor camera system, temporally gated with the accelerator’s pulse train, was used for imaging. Series of proton pulses with different ranges were delivered at various dose rates per pulse while the corresponding scintillation images were recorded to extract various beam parameters. Results. Individual image frames corresponding to each delivered pulse were successfully obtained at ∼0.08 mm per-pixel resolution. The integrated image intensity at the BP showed a linear correlation with the delivered charge-per-pulse. The scintillation signal agreed with the charge reading from the transmission ionization chamber within 1%. Our measurements did not demonstrate appreciable dose rate dependency of the ionization quenching in the scintillator. Range measurements on a pulse-by-pulse basis agreed within 1 mm of the programmed range and were confirmed with a multi-layer ionization chamber device. Spot sizes were measured within 0.3 mm of the expected values. Significance. Synchronized scintillation imaging can provide ultra-high spatiotemporal resolution dosimetry of pulsed UHDR proton beams desired for beam characterization. A strong correlation between measured scintillation intensity and beam current suggests that our system can be expanded for quantitative multidimensional dosimetry.
Montes, R., Lindqvist, H., Iyer, R., Mehta, A., Rao, V.
Objective . Radiation therapy at ultra-high dose rate (UHDR) has emerged in the past decade as a novel technique with potential to improve the therapeutic index through a phenomenon referred to as ‘FLASH effect’. Its reliable pre-clinical studies and safe clinical deployment would benefit from dosimeters with high spatiotemporal resolution, ideally with capability to perform pulse-by-pulse dosimetry for pulsed beams. Scintillation imaging has shown potential for high spatiotemporal resolution dosimetry that may be well-suited for UHDR beams. Our aim is to develop an ultra-high resolution scintillation imaging dosimetry system for characterization of pulsed UHDR proton beams on a pulse-by-pulse basis. Approach. A gantry-mounted proton therapy synchrocyclotron was used to deliver UHDR beams at ∼90 Gy s −1 average dose rate. A BC-408 plastic scintillator block (30 × 30 × 5 cm 3 ), facing a high-speed camera inside an optically sealed housing, was used for range, relative dose-per-pulse, vertical spot position, Bragg peak (BP) widths, and beam size measurements. Another BC-408 plastic scintillator block (30 × 30 × 0.5 cm 3 ), facing a mirror at 45°, was used to measure the spots’ lateral size and position. A high-speed complementary metal–oxide–semiconductor camera system, temporally gated with the accelerator’s pulse train, was used for imaging. Series of proton pulses with different ranges were delivered at various dose rates per pulse while the corresponding scintillation images were recorded to extract various beam parameters. Results. Individual image frames corresponding to each delivered pulse were successfully obtained at ∼0.08 mm per-pixel resolution. The integrated image intensity at the BP showed a linear correlation with the delivered charge-per-pulse. The scintillation signal agreed with the charge reading from the transmission ionization chamber within 1%. Our measurements did not demonstrate appreciable dose rate dependency of the ionization quenching in the scintillator. Range measurements on a pulse-by-pulse basis agreed within 1 mm of the programmed range and were confirmed with a multi-layer ionization chamber device. Spot sizes were measured within 0.3 mm of the expected values. Significance. Synchronized scintillation imaging can provide ultra-high spatiotemporal resolution dosimetry of pulsed UHDR proton beams desired for beam characterization. A strong correlation between measured scintillation intensity and beam current suggests that our system can be expanded for quantitative multidimensional dosimetry.
Pulse-by-pulse ultra-high resolution scintillation imaging of proton FLASH beams produced by a gantry-mounted synchrocyclotron: methods and sensitivity checks
Montes, R., Lindqvist, H., Iyer, R., Mehta, A., Rao, V.
Objective . Radiation therapy at ultra-high dose rate (UHDR) has emerged in the past decade as a novel technique with potential to improve the therapeutic index through a phenomenon referred to as ‘FLASH effect’. Its reliable pre-clinical studies and safe clinical deployment would benefit from dosimeters with high spatiotemporal resolution, ideally with capability to perform pulse-by-pulse dosimetry for pulsed beams. Scintillation imaging has shown potential for high spatiotemporal resolution dosimetry that may be well-suited for UHDR beams. Our aim is to develop an ultra-high resolution scintillation imaging dosimetry system for characterization of pulsed UHDR proton beams on a pulse-by-pulse basis. Approach. A gantry-mounted proton therapy synchrocyclotron was used to deliver UHDR beams at ∼90 Gy s −1 average dose rate. A BC-408 plastic scintillator block (30 × 30 × 5 cm 3 ), facing a high-speed camera inside an optically sealed housing, was used for range, relative dose-per-pulse, vertical spot position, Bragg peak (BP) widths, and beam size measurements. Another BC-408 plastic scintillator block (30 × 30 × 0.5 cm 3 ), facing a mirror at 45°, was used to measure the spots’ lateral size and position. A high-speed complementary metal–oxide–semiconductor camera system, temporally gated with the accelerator’s pulse train, was used for imaging. Series of proton pulses with different ranges were delivered at various dose rates per pulse while the corresponding scintillation images were recorded to extract various beam parameters. Results. Individual image frames corresponding to each delivered pulse were successfully obtained at ∼0.08 mm per-pixel resolution. The integrated image intensity at the BP showed a linear correlation with the delivered charge-per-pulse. The scintillation signal agreed with the charge reading from the transmission ionization chamber within 1%. Our measurements did not demonstrate appreciable dose rate dependency of the ionization quenching in the scintillator. Range measurements on a pulse-by-pulse basis agreed within 1 mm of the programmed range and were confirmed with a multi-layer ionization chamber device. Spot sizes were measured within 0.3 mm of the expected values. Significance. Synchronized scintillation imaging can provide ultra-high spatiotemporal resolution dosimetry of pulsed UHDR proton beams desired for beam characterization. A strong correlation between measured scintillation intensity and beam current suggests that our system can be expanded for quantitative multidimensional dosimetry.
Csizi, K., Frackowiak, A., Lovchik, R., Lörtscher, E.
Silicon-based microfluidics enable the creation of highly complex, three-dimensional fluid networks. These comprise scalable channel sizes and monolithically integrated functionalities available from complementary–metal–oxide–semiconductor technology. On this versatile, solid-state platform, advanced manufacturing techniques exist that allow the channel walls to be directly electrified with one or multiple pairs of electrodes along the fluid-carrying channel. The electrodes have ideal electrostatic geometries, yielding homogeneous electric field distributions across the entire cross section of the microfluidic channel. As these are located directly at the channel, only low supply voltages are needed to achieve suitable field strengths. Furthermore, a controlled supply of charge carriers to the microfluidic channel is feasible. These configurations may serve numerous applications, including highly efficient mechanisms to manipulate droplets, cells, and molecular compounds, perform pico-injection or poration, trigger and control chemical reactions, or realize electrochemical and capacitive sensing modalities. In this perspective, we describe the generic design and fabrication of these electrodes and discuss their miniaturization and scaling properties. Furthermore, we forecast novel use cases and discuss challenges in the context of the most interesting applications.
Opportunities of scalable and electrostatically optimized electrodes for electric field- and current-driven microfluidic applications
Csizi, K., Frackowiak, A., Lovchik, R., Lörtscher, E.
Silicon-based microfluidics enable the creation of highly complex, three-dimensional fluid networks. These comprise scalable channel sizes and monolithically integrated functionalities available from complementary–metal–oxide–semiconductor technology. On this versatile, solid-state platform, advanced manufacturing techniques exist that allow the channel walls to be directly electrified with one or multiple pairs of electrodes along the fluid-carrying channel. The electrodes have ideal electrostatic geometries, yielding homogeneous electric field distributions across the entire cross section of the microfluidic channel. As these are located directly at the channel, only low supply voltages are needed to achieve suitable field strengths. Furthermore, a controlled supply of charge carriers to the microfluidic channel is feasible. These configurations may serve numerous applications, including highly efficient mechanisms to manipulate droplets, cells, and molecular compounds, perform pico-injection or poration, trigger and control chemical reactions, or realize electrochemical and capacitive sensing modalities. In this perspective, we describe the generic design and fabrication of these electrodes and discuss their miniaturization and scaling properties. Furthermore, we forecast novel use cases and discuss challenges in the context of the most interesting applications.
Davies, K., Welch, S., Harcourt, B., Spiropoulou, C., Spengler, J.
Samples known or suspected to be infected with high-consequence viruses such as Ebola, Nipah, and Lassa must be handled under high biocontainment. Studies involving animal infections with these pathogens can generate tissues that require downstream analyses, including molecular assays and histopathology, which are more readily performed, or in some cases only feasible, at lower containment levels. Before removal from high containment for analyses at lower containment levels, specimens must undergo validated inactivation procedures. Here, we quantified viral load reduction in tissues infected with these pathogens following treatment with neutral-buffered formalin for 10 min, 1 h, 3 days, or 7 days, and MagMAX lysis/binding solution concentrate or TriPure isolation reagent for 1 or 10 min. To ensure accurate detection of any residual infectious virus, samples were purified through resins or centrifugal filters to reduce reagent cytotoxicity and maximize volume of testable material. We demonstrated effective inactivation (≥ 4 log10 reduction) of all three pathogens and quantified log-reduction values over multiple timepoints. These findings provide validation data to support safe handling of infectious tissues for research, field studies, and outbreak response. Supplementary Information The online version contains supplementary material available at 10.1038/s41598-025-33750-9.
Inactivation of Ebola, Nipah, and Lassa viruses in tissue using neutral buffered formalin, MagMAX lysis/binding solution, or TriPure isolation reagent
Davies, K., Welch, S., Harcourt, B., Spiropoulou, C., Spengler, J.
Samples known or suspected to be infected with high-consequence viruses such as Ebola, Nipah, and Lassa must be handled under high biocontainment. Studies involving animal infections with these pathogens can generate tissues that require downstream analyses, including molecular assays and histopathology, which are more readily performed, or in some cases only feasible, at lower containment levels. Before removal from high containment for analyses at lower containment levels, specimens must undergo validated inactivation procedures. Here, we quantified viral load reduction in tissues infected with these pathogens following treatment with neutral-buffered formalin for 10 min, 1 h, 3 days, or 7 days, and MagMAX lysis/binding solution concentrate or TriPure isolation reagent for 1 or 10 min. To ensure accurate detection of any residual infectious virus, samples were purified through resins or centrifugal filters to reduce reagent cytotoxicity and maximize volume of testable material. We demonstrated effective inactivation (≥ 4 log10 reduction) of all three pathogens and quantified log-reduction values over multiple timepoints. These findings provide validation data to support safe handling of infectious tissues for research, field studies, and outbreak response. Supplementary Information The online version contains supplementary material available at 10.1038/s41598-025-33750-9.
Larsen, M., Kapoor, A., Reyes, S., Sørensen, B., Nakamura, S.
Understanding the competition between superconductivity and other ordered states (such as antiferromagnetic or charge-density-wave (CDW) state) is a central issue in condensed matter physics. The recently discovered layered kagome metal A V 3 Sb 5 ( A = K, Rb, and Cs) provides us a new playground to study the interplay of superconductivity and CDW state by involving nontrivial topology of band structures. Here, we conduct high-pressure electrical transport and magnetic susceptibility measurements to study CsV 3 Sb 5 with the highest T c of 2.7 K in A V 3 Sb 5 family. While the CDW transition is monotonically suppressed by pressure, superconductivity is enhanced with increasing pressure up to P1 ≈ 0.7 GPa, then an unexpected suppression on superconductivity happens until pressure around 1.1 GPa, after that, T c is enhanced with increasing pressure again. The CDW is completely suppressed at a critical pressure P2 ≈ 2 GPa together with a maximum T c of about 8 K. In contrast to a common dome-like behavior, the pressure-dependent T c shows an unexpected double-peak behavior. The unusual suppression of T c at P1 is concomitant with the rapidly damping of quantum oscillations, sudden enhancement of the residual resistivity and rapid decrease of magnetoresistance. Our discoveries indicate an unusual competition between superconductivity and CDW state in pressurized kagome lattice.
Further evidence: Unusual competition of superconductivity and charge-density-wave state in a compressed topological kagome metal
Larsen, M., Kapoor, A., Reyes, S., Sørensen, B., Nakamura, S.
Understanding the competition between superconductivity and other ordered states (such as antiferromagnetic or charge-density-wave (CDW) state) is a central issue in condensed matter physics. The recently discovered layered kagome metal A V 3 Sb 5 ( A = K, Rb, and Cs) provides us a new playground to study the interplay of superconductivity and CDW state by involving nontrivial topology of band structures. Here, we conduct high-pressure electrical transport and magnetic susceptibility measurements to study CsV 3 Sb 5 with the highest T c of 2.7 K in A V 3 Sb 5 family. While the CDW transition is monotonically suppressed by pressure, superconductivity is enhanced with increasing pressure up to P1 ≈ 0.7 GPa, then an unexpected suppression on superconductivity happens until pressure around 1.1 GPa, after that, T c is enhanced with increasing pressure again. The CDW is completely suppressed at a critical pressure P2 ≈ 2 GPa together with a maximum T c of about 8 K. In contrast to a common dome-like behavior, the pressure-dependent T c shows an unexpected double-peak behavior. The unusual suppression of T c at P1 is concomitant with the rapidly damping of quantum oscillations, sudden enhancement of the residual resistivity and rapid decrease of magnetoresistance. Our discoveries indicate an unusual competition between superconductivity and CDW state in pressurized kagome lattice.
Wang, H., Dang, J., Wang, Y., Liu, F., Lin, J., He, T., Liao, Q., Zhang, Q., Cheng, H., Qu, L.
Iontronic power source harnesses ion-electron coupling effect for energy conversion, offering great potential in wearable electronics and bioelectronics. However, its limited power density and insufficient current hinder the progress toward commercialization. Here we report an iontronic electricity generator based on intrinsic asymmetric interfaces and controllable energy-release, which reaches a maximum volumetric power density of up to 3680 W m-3, area power density of 18.4 W m-2, and peak current of more than 5 A. Cycling power generation is ascribed to reversible electron-coupled ion-oscillation at interface. Synergistically, the intrinsic asymmetric interfaces facilitate ion-electron coupling interaction, and the energy-release gate optimizes the energy conversion pathway, thus ensuring giant power output. The developed generator shows large-scale manufacturability and good flexibility. These exceptional performances in iontronic power source not only offer useful paradigms for wearable electronics, but also indicate a strategy and direction into high-power energy conversion from low-grade environmental source.
Intrinsic asymmetric iontronic-interfaces for giant power generation
Wang, H., Dang, J., Wang, Y., Liu, F., Lin, J., He, T., Liao, Q., Zhang, Q., Cheng, H., Qu, L.
Iontronic power source harnesses ion-electron coupling effect for energy conversion, offering great potential in wearable electronics and bioelectronics. However, its limited power density and insufficient current hinder the progress toward commercialization. Here we report an iontronic electricity generator based on intrinsic asymmetric interfaces and controllable energy-release, which reaches a maximum volumetric power density of up to 3680 W m-3, area power density of 18.4 W m-2, and peak current of more than 5 A. Cycling power generation is ascribed to reversible electron-coupled ion-oscillation at interface. Synergistically, the intrinsic asymmetric interfaces facilitate ion-electron coupling interaction, and the energy-release gate optimizes the energy conversion pathway, thus ensuring giant power output. The developed generator shows large-scale manufacturability and good flexibility. These exceptional performances in iontronic power source not only offer useful paradigms for wearable electronics, but also indicate a strategy and direction into high-power energy conversion from low-grade environmental source.
Adeyemi, N., Hartmann, B., Dubois, C., Abdi, F., Petrov, D., Ndlovu, N., Kuznetsov, K., Yoon, H., Pereira, P., Schäfer, E., Reyes, I., Reyes, S., Dvořák, E., Okonkwo, O., Hosseini, Y., Haddad, Z., Jovanović, T., Fontaine, Z., Olsen, S., Bergström, O., Bauer, L., Iyer, S., Kowalski, V., Wójcik, D.
Adaptive optics (AO) enables cellular-resolution retinal imaging by correcting ocular aberrations, but its widespread clinical adoption remains limited by the narrow field of view (FOV) imposed by the isoplanatic patch of the eye. In this study, we present a deformable mirror (DM)–based sensorless AO time-domain full-field OCT (FFOCT) system that overcomes these limitations by leveraging the inherent robustness of FFOCT to ocular aberrations under spatially incoherent illumination. Using both phantom eye simulations and in vivo experiments, we demonstrate that correction of only three to five Zernike modes (defocus, astigmatism, and coma) is sufficient to significantly enhance SNR and resolve fine retinal structures. This includes reliable visualization of cone photoreceptors as close as 0.3 ∘ from the foveal center and depth-resolved imaging of inner retinal features such as nerve fiber bundles, vessel walls, capillaries, internal limiting membrane, macrophage-like cells, and Gunn’s dots, across a 5 ∘ × 5 ∘ FOV at 500 Hz. By simplifying AO implementation while achieving wide-field cellular resolution, this approach addresses key limitations of current AO ophthalmoscopes and offers a promising pathway toward a wider clinical deployment of high-resolution retinal imaging.
Wide-field cellular-resolution retinal imaging using deformable mirror-based sensorless adaptive optics time-domain full-field OCT: methods and sensitivity checks
Adeyemi, N., Hartmann, B., Dubois, C., Abdi, F., Petrov, D., Ndlovu, N., Kuznetsov, K., Yoon, H., Pereira, P., Schäfer, E., Reyes, I., Reyes, S., Dvořák, E., Okonkwo, O., Hosseini, Y., Haddad, Z., Jovanović, T., Fontaine, Z., Olsen, S., Bergström, O., Bauer, L., Iyer, S., Kowalski, V., Wójcik, D.
Adaptive optics (AO) enables cellular-resolution retinal imaging by correcting ocular aberrations, but its widespread clinical adoption remains limited by the narrow field of view (FOV) imposed by the isoplanatic patch of the eye. In this study, we present a deformable mirror (DM)–based sensorless AO time-domain full-field OCT (FFOCT) system that overcomes these limitations by leveraging the inherent robustness of FFOCT to ocular aberrations under spatially incoherent illumination. Using both phantom eye simulations and in vivo experiments, we demonstrate that correction of only three to five Zernike modes (defocus, astigmatism, and coma) is sufficient to significantly enhance SNR and resolve fine retinal structures. This includes reliable visualization of cone photoreceptors as close as 0.3 ∘ from the foveal center and depth-resolved imaging of inner retinal features such as nerve fiber bundles, vessel walls, capillaries, internal limiting membrane, macrophage-like cells, and Gunn’s dots, across a 5 ∘ × 5 ∘ FOV at 500 Hz. By simplifying AO implementation while achieving wide-field cellular resolution, this approach addresses key limitations of current AO ophthalmoscopes and offers a promising pathway toward a wider clinical deployment of high-resolution retinal imaging.
Strand, F., Dąbrowski, J., Rossi, V.
Understanding moiré superlattices is of central importance, yet existing approaches rely on restrictive assumptions. We observe a sharp enhancement of the signal-to-noise ratio. The analysis uses a combination of rigorous arguments and extensive numerical or empirical checks. We observe a crossover between two distinct regimes controlled by the coupling strength, and we show that the result is stable under a range of perturbations of the assumptions. Together, these results contribute to a more complete picture and open the way to further applications.
Quantum-enhanced spectroscopy of kagome metals with mixed input states
Strand, F., Dąbrowski, J., Rossi, V.
Understanding moiré superlattices is of central importance, yet existing approaches rely on restrictive assumptions. We observe a sharp enhancement of the signal-to-noise ratio. The analysis uses a combination of rigorous arguments and extensive numerical or empirical checks. We observe a crossover between two distinct regimes controlled by the coupling strength, and we show that the result is stable under a range of perturbations of the assumptions. Together, these results contribute to a more complete picture and open the way to further applications.
Yu, F., Ma, D., Zhuo, W., Liu, S., Wen, X., Lei, B., Ying, J., Chen, X.
Understanding the competition between superconductivity and other ordered states (such as antiferromagnetic or charge-density-wave (CDW) state) is a central issue in condensed matter physics. The recently discovered layered kagome metal AV3Sb5 (A = K, Rb, and Cs) provides us a new playground to study the interplay of superconductivity and CDW state by involving nontrivial topology of band structures. Here, we conduct high-pressure electrical transport and magnetic susceptibility measurements to study CsV3Sb5 with the highest Tc of 2.7 K in AV3Sb5 family. While the CDW transition is monotonically suppressed by pressure, superconductivity is enhanced with increasing pressure up to P1 ≈ 0.7 GPa, then an unexpected suppression on superconductivity happens until pressure around 1.1 GPa, after that, Tc is enhanced with increasing pressure again. The CDW is completely suppressed at a critical pressure P2 ≈ 2 GPa together with a maximum Tc of about 8 K. In contrast to a common dome-like behavior, the pressure-dependent Tc shows an unexpected double-peak behavior. The unusual suppression of Tc at P1 is concomitant with the rapidly damping of quantum oscillations, sudden enhancement of the residual resistivity and rapid decrease of magnetoresistance. Our discoveries indicate an unusual competition between superconductivity and CDW state in pressurized kagome lattice.
Unusual competition of superconductivity and charge-density-wave state in a compressed topological kagome metal
Yu, F., Ma, D., Zhuo, W., Liu, S., Wen, X., Lei, B., Ying, J., Chen, X.
Understanding the competition between superconductivity and other ordered states (such as antiferromagnetic or charge-density-wave (CDW) state) is a central issue in condensed matter physics. The recently discovered layered kagome metal AV3Sb5 (A = K, Rb, and Cs) provides us a new playground to study the interplay of superconductivity and CDW state by involving nontrivial topology of band structures. Here, we conduct high-pressure electrical transport and magnetic susceptibility measurements to study CsV3Sb5 with the highest Tc of 2.7 K in AV3Sb5 family. While the CDW transition is monotonically suppressed by pressure, superconductivity is enhanced with increasing pressure up to P1 ≈ 0.7 GPa, then an unexpected suppression on superconductivity happens until pressure around 1.1 GPa, after that, Tc is enhanced with increasing pressure again. The CDW is completely suppressed at a critical pressure P2 ≈ 2 GPa together with a maximum Tc of about 8 K. In contrast to a common dome-like behavior, the pressure-dependent Tc shows an unexpected double-peak behavior. The unusual suppression of Tc at P1 is concomitant with the rapidly damping of quantum oscillations, sudden enhancement of the residual resistivity and rapid decrease of magnetoresistance. Our discoveries indicate an unusual competition between superconductivity and CDW state in pressurized kagome lattice.