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A 570 meV emission shift is achieved through surface-enhanced Landau damping during phase transitions. In crystalline Sb₂Te₃, localized surface plasmons facilitate hot-electron injection, shifting the emission energy from 1.64 to 2.21 eV. This tunability is further enhanced by applying a DC voltage bias, making it suitable for integration with on-chip quantum photonic systems.

Abstract

Tuning quantum emission to a specific wavelength at room temperature holds significant promise for enhancing secure quantum communication, particularly by aligning with the Fraunhofer lines in the solar spectrum. The integration of quantum emitters with phase-change materials enables emission wavelength modulation, especially when strong field enhancement is present. Antimony telluride (Sb2Te3) exhibits the potential to facilitate this functionality through its support of interband plasmonics and phase-change behavior. In this study, Sb₂Te₃ antennae are designed and fabricated to tune the emission energy of adjacent perovskite quantum dots (QDs) by over 570 meV. The underlying mechanism involves the localized surface plasmons (LSPs) on Sb₂Te₃ nanostructures, which exhibit a surface-enhanced Landau damping process that facilitates the decay of LSPs into electron-hole pairs. The generated hot electrons are then injected into perovskite QDs via the microscopic electron transport process, which can be triggered by the transition of Sb2Te3 from amorphous to a crystalline state, resulting in a significant emission energy shift from 1.64 to 2.21 eV. Furthermore, the emission energy of perovskite QDs on crystalline Sb₂Te₃ nanoantennae can be modulated through DC voltage bias, highlighting the potential for extensive wavelength tunability of quantum emitters integrated with electronic systems.

Three morphologies of spinel catalysts for the decomposition of polyethylene terephthalate (PET) are prepared by hydrothermal method. The optimization of morphology made a positive impact on PET conversion, yield of bis(2-hydroxyethyl) terephthalate (BHET), and photocatalytic performance. Catalyst with octahedral morphology has an optimum content of oxygen vacancies, which can work as active sites to promote PET degradation.

Abstract

Thermocatalytic recycling of plastics is typically constrained by high energy input requirements, resulting in poor economic efficiency and necessitating the utilization of light power. Indeed, photothermal catalysis offers several advantages over traditional photocatalysis and enables more efficient use of light energy. In this study, unique octahedral spinel-structured cobalt manganese oxide (CoMn2O4) catalysts are prepared. CoMn2O4 acts as both a photothermal reagent and catalyst, demonstrating low light intensity requirements, high conversion rates, enhanced reactivity, and superior stability during polyethylene terephthalate (PET) glycolysis via photothermocatalysis. Oxygen vacancies created on CoMn2O4 facilitate PET glycolysis by providing reactive sites that promote nucleophilic addition and subsequent elimination reactions. The spinel structure of CoMn2O4 ensures high thermal stability, while the octahedral configuration enhances the optical absorption coefficient and photothermal conversion efficiency. Under identical conditions, the PET conversion efficiency of CoMn2O4 in photothermal catalysis is 3.1 times higher than under purely thermal conditions, while maintaining high selectivity for high-value monomers. This study presents a new catalyst design approach for highly efficient upcycling of plastics, highlighting its substantial potential in this field.

An in situ polymerization strategy is rationally proposed to synthesize cross-linked polymer solid-state electrolyte and polymer-encapsulated graphite cathode, which achieves intimate interface contact, dendrite free, flame retardancy, and confined volume expansion, enabling a solid-state aluminum-graphite battery with high-areal-capacity, high-safety, and long-lasting lifespan.

Abstract

Nonaqueous rechargeable aluminum batteries (RABs) attract intense interest due to their low-cost, high-capacity, and high-safety using nonflammable chloroaluminate ionic liquid electrolytes (ILEs). However, Al dendrite growth, interface degradation, and corrosiveness remain challenges in these ILEs. Herein, an ultrastable solid-state aluminum battery (SAB) based on a cross-linked polymer solid-state electrolyte (PSE) and a PSE-encapsulated graphite (PG) cathode is constructed via an in situ polymerization strategy, which maintains battery safety and realizes a synergy of interface compatibility between PSE/PG and PSE/Al interfaces. The PSE has a high room temperature ionic conductivity of 4.15 × 10−3 S cm−1 and a low corrosiveness to Al anode, ensuring rapid and continuous transportation of chloroaluminate ions and homogeneous plating/stripping of metallic Al. In addition, the volume expansion of the PG cathode is almost negligible owing to the confinement effect of graphite within the cross-linked polymer skeleton. As a consequence, the assembled SAB demonstrates high areal capacity (0.67 mAh cm−2 at 0.1 mA cm−2), good rate performance, and impressive cycling stability (no capacity attenuation after 10 000 cycles). Such in situ polymerization strategy shows a broader promise for the development of safe and stable RABs in energy storage applications.

The coupling strategies between multi-physical fields and photoelectric effects in 2D material-based photodetectors are systematically summarized in this review. It highlights the effects of their synergistic mechanisms on energy band structures, carrier dynamics, and device performance. The article concludes with future research directions, providing a roadmap for developing high-performance intelligent optoelectronic devices.

Abstract

2D materials possess exceptional carrier transport properties and mechanical stability despite their ultrathin nature. In this context, the coupling between polarization fields and photoelectric fields has been proposed to modulate the physical properties of 2D materials, including energy band structure, carrier mobility, as well as the dynamic processes of photoinduced carriers. These strategies have led to significant improvements in the performance, functionality, and integration density of 2D materials -based photodetectors. The present review introduces the coupling of photoelectric field with four fundamental polarization fields, delivered from dielectric, piezoelectric, pyroelectric, and ferroelectric effects, focusing on their synergistic coupling mechanisms, distinctive properties, and technological merits in advanced photodetection applications. More importantly, it sheds light on the new path of material synthesis and novel structure design to improve the efficiency of the coupling strategies in photodetectors. Then, research advances on the synergy of multi-polarization effects and photoelectric effect in the domain of bionic photodetectors are highlighted. Finally, the review outlines the future research perspectives of coupling strategies in 2D materials-based photodetectors and proposes potential solutions to address the challenges issues of this area. This comprehensive overview will guide futural fundamental and applied research that capitalizes on coupling strategies for sensitive and intelligent photodetection.

The ultraviolet laser irradiation is used to cut off the outer shell of double-walled carbon nanotubes (DWCNTs). A velocity-dependent intershell friction occurs between the outer and inner shells. This friction results from dynamic localized commensurate contacts. The friction-induced intershell locking enhances the dynamic strength of DWCNTs to over 90 GPa, indicating that DWCNTs possess exceptional resistance to high-velocity impacts.

Abstract

Low-dimensional ultra-strong nanomaterials have attracted great anticipation for applications under extreme dynamic conditions. A photocatalytic method is developed to selectively cut off the outer shell of double-walled carbon nanotubes (DWCNTs), achieving non-contact measurement of intershell friction with both high temporal and spatial resolutions at high sliding velocities under optical microscope. The intershell friction linearly increases with the sliding velocity, with a slope related to intershell distance and chirality of DWCNTs. The maximum measured friction reaches 194.1 ± 7.3 nN at a sliding velocity of 977 mm s−1, a value comparable to the tensile force (≈450 nN) for breaking the outer shell. Molecular dynamics simulations indicate that the velocity-dependent intershell friction is related to dynamic localized commensurate contacts. The friction-induced “intershell locking” enhances the effective dynamic strength of DWCNTs from 64.8 ± 3.4 GPa to 90.1 ± 4.0 GPa at a tensile strain rate of 3300 s−1. This study reveals anomalous friction mechanisms at nanoscale and demonstrates promising application of DWCNTs as ultra-strong materials.

By proposing a single-cell order-decoupling method and simultaneously manipulating four-dimensional optical parameters (Wavelength, Wavevector Direction, Polarization, and Diffraction Order), a meta-optics storage system accomplishes multidimensional optical encryption. This system achieves up to sixteen-channel multidimensional encrypted holographic images with high quality and exponentially raises the threshold of brute-force decoding, and thus remarkably enhances information security in optical storage.

Abstract

Recent advancements in multidimensional multiplexing have paved the way for meta-optics encryption to be a viable solution to next-generation information storage and encryption security. However, challenges persist in increasing simultaneously modulated dimensions while minimizing structural complexity. Here, a novel single-cell order-decoupling method is proposed for the realization of a multidimensional encrypted meta-optics storage system. By analyzing the mathematic relationships between the phases of different diffraction orders, the detour phase structure is optimized to achieve independent encoding freedom for multiple orders. The proposed multidimensional encrypted meta-optics successfully realize the concurrent modulation of four optical dimensions: i) Wavelength, ii) Wavevector Direction, iii) Polarization, and iv) Diffraction Order. The system achieves up to sixteen-channel meta-holograms with low crosstalk and exponentially raises the threshold of brute-force decoding and thus remarkably enhances the information security in optical storage. It envisioned that the on-chip metasurface-based multidimensional encrypted strategy for augmented reality display functionalities presents promising applications in optical encryption/storage, anti-counterfeiting, and multifunctional photonics integrated circuits.

Nature Materials, Published online: 10 March 2025; doi:10.1038/s41563-025-02134-9

An isolation strategy is presented to improve the stability of metal nanoparticles by grafting oxide nano-islands between the support and the nanoparticles. This enhances sintering resistance, with the mean size of the nanoparticles maintained at 1.4 nm after 400 h of catalytic dry reforming of methane.

Nature Materials, Published online: 10 March 2025; doi:10.1038/s41563-025-02144-7

Resonant inelastic X-ray scattering measurements suggest that the oxidized oxygen species in high-energy Li-rich oxide cathodes are trapped molecular O2, which is also observed in O-redox-inactive materials. This suggests that resonant X-ray inelastic scattering measurements generate these species, and molecular O2 is not responsible for voltage hysteresis and decay.

Sharp threshold for the ballisticity of the random walk on the exclusion process

In this talk, I will overview works on random walks in dynamical random environments. I will recall a result obtained in collaboration with Hilario and Teixeira and then I will focus on a work with Conchon—Kerjan and Rodriguez. Our main interest is to investigate the long-term behavior of a random walker evolving on top of the simple symmetric exclusion process (SSEP) at equilibrium, with density in [0,1]. At each jump, the random walker is subject to a drift that depends on whether it is sitting on top of a particle or a hole. We prove that the speed of the walk, seen as a function of the density, exists for all density but at most one, and that it is strictly monotonic. We will explain how this can be seen as a sharpness result and provide an outline of the proof, whose general strategy is inspired by techniques developed for studying the sharpness of strongly-correlated percolation models.

• Speaker: Daniel Kious (Bath)
• Tuesday 11 March 2025, 14:00-15:00
• Venue: MR12.
• Series: Probability; organiser: ww295.

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Biological design with machine learning and limited data.

AI and machine learning have rapidly emerged as promising tools for cellular engineering and optimisation. Yet the complexities of biological measurements often limit the applicability of state-of-the-art algorithms that require large and well-curated data for training. This gap could potentially leave behind many academic and industry laboratories that could hugely benefit from this technology. In this talk, I will describe recent applications of machine learning for in silico discovery and optimisation, with a focus on small and heterogeneous datasets typically encountered in biological design tasks. Examples include predicting protein expression/function from sequence information, low-N drug discovery against complex diseases, and optimisation of gene circuits for metabolite production.

The seminar will be held in LR3A , Department of Engineering, and online (zoom): https://newnham.zoom.us/j/92544958528?pwd=YS9PcGRnbXBOcStBdStNb3E0SHN1UT09

• Speaker: Diego Oyarzun, University of Edinburgh
• Thursday 13 March 2025, 14:00-15:00
• Venue: LR3A, Department of Engineering and online (Zoom).
• Series: CUED Control Group Seminars; organiser: Fulvio Forni.

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Integrating Random Memory Patterns and Spatial Maps in Food-Caching Birds

A major challenge in neuroscience is understanding how the hippocampus encodes numerous episodic memories without interference while maintaining spatial representations. While theoretical considerations favour random, uncorrelated patterns for episodic memory storage, most experimental studies focus on spatial memory that is highly structured. In this journal club, we will explore recent work in chickadees, a species that relies on precise memory for food caching, to investigate how hippocampal circuits integrate random patterns with structured spatial codes. The first study [1] demonstrates that place cells not only encode an animal’s location but also respond when the bird gazes at distant locations, suggesting a unified hippocampal representation of attended space. The second study [2] identifies sparse, high-dimensional ‘barcode’ patterns that uniquely label individual caching events, coexisting with conventional place cell activity but remaining mostly uncorrelated to spatial proximity. The third study [3] presents a computational model in which chaotic recurrent network dynamics generate barcodes that serve as memory indices while maintaining a structured code for spatial memory. Together, these findings bridge theoretical ideas of hippocampal indexing with empirical data, offering a new perspective on how the brain simultaneously supports spatial navigation and episodic memory storage. [1] Payne, H. L., & Aronov, D. (2024). Remote activation of place codes by gaze in a highly visual animal. bioRxiv, 2024-09. [2] Chettih, S. N., Mackevicius, E. L., Hale, S., & Aronov, D. (2024). Barcoding of episodic memories in the hippocampus of a food-caching bird. Cell, 187(8), 1922-1935. [3] Fang, C., Lindsey, J., Abbott, L. F., Aronov, D., & Chettih, S. (2024). Barcode activity in a recurrent network model of the hippocampus enables efficient memory binding. bioRxiv.

• Speaker: Speaker to be confirmed
• Tuesday 11 March 2025, 15:00-16:30
• Venue: CBL Seminar Room, Engineering Department, 4th floor Baker building.
• Series: Computational Neuroscience; organiser: .

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Energy Environ. Sci., 2025, Accepted Manuscript
DOI: 10.1039/D4EE04927F, Review Article Open Access &nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.Weihan Li, Minsi Li, Haoqi Ren, Jung Tae Kim, Ruying Li, Tsun-Kong Sham, Xueliang Sun
Nitride solid-state electrolytes (SSEs) hold significant potential for addressing critical interfacial issues between SSEs and lithium metal in all-solid-state lithium metal batteries. These batteries are at the forefront of energy...
The content of this RSS Feed (c) The Royal Society of Chemistry

Energy Environ. Sci., 2025, Accepted Manuscript
DOI: 10.1039/D5EE00031A, PaperTainan Duan, Jia Wang, Xiaochan Zuo, Yanyi Zhong, Yuhong Long, Peiran Wang, Kaihuai Tu, Cheng Zhong, Jiangbin Zhang, Oleg Alekseevich Rakitin, Zhaoyang Yao, Xiangjian Wan, Yan Zhao, Bin Kan, Yongsheng Chen
The development of high-performance organic electron acceptors is pivotal for advancing organic optoelectronic devices. In this paper, a new synthetic approach was developed to construct fused-ring aromatic backbones and the...
The content of this RSS Feed (c) The Royal Society of Chemistry

Formal verification of the 5th Busy Beaver value

We prove that S(5) = 47,176,870. The Busy Beaver value S(n) gives the maximum number of steps a halting n-state 2-symbol Turing machine can perform from the all-0 tape before halting and S was historically introduced as one of the simplest examples of a noncomputable function.

Using the Coq proof assistant, we enumerate 181,385,789 5-state Turing machines, and for each, decide whether it halts or not. Most of these machines are decided using new algorithms that simplify the halting problem by building Finite State Automata to approximate the machine’s set of reachable configurations. For 13 challenging Sporadic Machines, we provide individual Coq proofs of nonhalting.

Our result marks the first determination of a new Busy Beaver value in over 40 years, leveraging Coq’s computing capabilities and demonstrating the effectiveness of collaborative online research.

• Speaker: Tristan Stérin (Maynooth University, Ireland) and Maja Kądziołka
• Thursday 13 March 2025, 17:00-18:00
• Venue: MR14 Centre for Mathematical Sciences.
• Series: Formalisation of mathematics with interactive theorem provers ; organiser: Anand Rao Tadipatri.

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Energy Environ. Sci., 2025, Accepted Manuscript
DOI: 10.1039/D5EE00136F, Review Article Open Access &nbsp This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.Huihua Li, Fanglin Wu, Jian Wang, Jingxuan Wang, Hongxu Qu, Minghua Chen, Huang Zhang, Stefano Passerini
Anode-free sodium metal batteries (AFSMBs) represent a significant advancement in energy storage technology, offering high energy density and cost-effective solutions. However, their applications are impeded by the critical sodium deposition...
The content of this RSS Feed (c) The Royal Society of Chemistry

A short and personal history of planar cell polarity

Abstract not available

• Speaker: Peter A. Lawrence - Department of Zoology
• Wednesday 02 April 2025, 16:00-17:30
• Venue: Max Perutz Lecture Theatre. LMB. Cambridge..
• Series: Cambridge Fly Meetings; organiser: Daniel Sobrido-Cameán.

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The fly connectome

Abstract not available

• Speaker: Tomke Stürner - Drosophila Connectomics Group, Department of Zoology and Neurobiology Division, MRC Laboratory of Molecular Biology
• Wednesday 02 April 2025, 16:00-17:30
• Venue: Max Perutz Lecture Theatre. LMB. Cambridge..
• Series: Cambridge Fly Meetings; organiser: Daniel Sobrido-Cameán.

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Title to be confirmed

Abstract not available

• Speaker: Marcin Mucha-Kruczynski (Bath)
• Friday 14 March 2025, 14:00-15:30
• Venue: TCM Seminar Room.
• Series: Theory of Condensed Matter; organiser: Bo Peng.

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Dr Ewan Harrison, Wellcome Sanger Institute

This Cambridge Immunology and Medicine Seminar will take place on Thursday 5 June 2025, starting at 4:00pm, in the Ground Floor Lecture Theatre, Jeffrey Cheah Biomedical Centre (JCBC)

Speaker: Dr Ewan Harrison, Head of Respiratory Virus and Microbiome Initiative, Wellcome Trust Sanger Institute

Title: TBC

Host: Patrycja Kozik, MRC -LMB, Cambridge

Refreshments will be available following the seminar.

• Speaker: Dr Ewan Harrison, Wellcome Sanger Institute
• Thursday 05 June 2025, 16:00-17:00
• Venue: Lecture Theatre, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus.
• Series: Cambridge Immunology Network Seminar Series; organiser: Ruth Paton.

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Prof. Vincenzo Bronte, Universita di Verona, Italy

This Cambridge Immunology and Medicine Seminar will take place on Thursday 22 May 2025, starting at 4:00pm, in the Ground Floor Lecture Theatre, Jeffrey Cheah Biomedical Centre (JCBC)

Speaker: Prof. Vincenzo Bronte, Universita di Verona, Italy

Title: TBC

Host: Virginia Pedicord, CITIID , Cambridge

Refreshments will be available following the seminar.

• Speaker: Prof. Vincenzo Bronte, Universita di Verona, Italy
• Thursday 22 May 2025, 16:00-17:00
• Venue: Lecture Theatre, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus.
• Series: Cambridge Immunology Network Seminar Series; organiser: Ruth Paton.

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