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NanoManufacturing

Michael De Volder, Engineering Department - IfM
 

Self‐Powered Artificial Neuron Devices: Towards the All‐In‐One Perception and Computation System

This review summarizes the recent advancements in self-powered artificial neuron devices (ANDs), with a particular emphasis on mechanical and optical energy sources, operational modes, fundamental mechanisms, device architectures, and application in all-in-one environmental perception systems. In addition, the challenges and perspectives in this field are discussed to inspire further development and facilitate future application.


Abstract

The increasing demand for energy supply in sensing units and the computational efficiency of computation units has prompted researchers to explore novel, integrated technology that offers high efficiency and low energy consumption. Self-powered sensing technology enables environmental perception without external energy sources, while neuromorphic computation provides energy-efficient and high-performance computing capabilities. The integration of self-powered sensing technology and neuromorphic computation presents a promising solution for an all-in-one system. This review examines recent developments and advancements in self-powered artificial neuron devices based on triboelectric, piezoelectric, and photoelectric effects, focusing on their structures, mechanisms, and functions. Furthermore, it compares the electrical characteristics of various types of self-powered artificial neuron devices and discusses effective methods for enhancing their performance. Additionally, this review provides a comprehensive summary of self-powered perception systems, encompassing tactile, visual, and auditory perception systems. Moreover, it elucidates recently integrated systems that combine perception, computing, and actuation units into all-in-one configurations, aspiring to realize closed-loop control. The seamless integration of self-powered sensing and neuromorphic computation holds significant potential for shaping a more intelligent future for humanity.

Mechanically Compatible Sealing of Hydrogel with Coherent Interface

A mechanically compatible seal is proposed for preventing hydrogels from water loss and swelling. This seal is made of a carbon-based elastomer blended with oligomers for controlling modulus and with polar polymeric domains for forming coherent interfaces, resulting in orders of magnitude improvements in the longevity of hydrogels without sacrificing their softness and stretchability.


Abstract

Long-term operation of hydrogels relies on protective coatings to avoid water swelling or evaporation, but these protections often cause substantial decreases in overall softness and stretchability. Here, a mechanically compatible seal with a coherent interfacial design is developed to encapsulate hydrogels. This seal is made from polybutylene (PIB) and polypropylene-graft-maleic anhydride (PP-g-MAH) blended poly(styrene-isobutylene-styrene) (SIBS). The PIB oligomers soften the SIBS networks, while the MAH groups facilitate covalent bonding between the SIBS and hydrogel. The sealed hydrogel exhibits an elastic modulus of 24 kPa and an elongation at a break of >1000%, both comparable to those of the pristine hydrogel. The adhesion energy between the seal and hydrogel reached >140 J m−2 and can be further increased to >400 J m−2 by a thermal treatment. This tough interface, together with the intrinsically low water vapor transmission rate of SIBS, allows the sealed hydrogel to maintain its modulus and stretchability after 10 days of drying in air. The sealed hydrogel is chemically and mechanically stable under harsh conditions, including acidic/alkaline/salty solutions, high temperatures, and cyclic mechanical deformation. This strategy applies to various hydrogels with diverse compositions and structures, leading to orders of magnitude improvements in the longevity of hydrogel-based electronic devices.

Violet to Near‐Infrared Optical Addressing of Spin Pairs in Hexagonal Boron Nitride

Spin-dependent optical emission is observed in hexagonal boron nitride across a wide band of wavelengths from the violet to the near-infrared, and attributed to spin defect pairs. These broadband spin pairs are found to exist naturally in a variety of samples from bulk crystals to powders to epitaxial films, and can be coherently controlled across the entire wavelength range.


Abstract

Optically addressable solid-state spins are an important platform for practical quantum technologies. Van der Waals material hexagonal boron nitride (hBN) is a promising host as it contains a wide variety of optical emitters, but thus far observations of addressable spins have been sparse, and most of them lacked a demonstration of coherent spin control. Here, robust optical readout of spin pairs in hBN is demonstrated with emission wavelengths spanning from violet to the near-infrared. It is found that these broadband spin pairs exist naturally in a variety of hBN samples from bulk crystals to powders to epitaxial films, and can be coherently controlled across the entire wavelength range. Furthermore, the optimal wavelengths are identified for independent readout of spin pairs and boron vacancy spin defects co-existing in the same sample. These results establish the ubiquity of the optically addressable spin pair system in hBN across a broad parameter space, making it a versatile playground for spin-based quantum technologies.

Cooperative Magnetic Interfacial Microrobot Couplefor Versatile Non‐Contact Biomedical Applications

A novel robotic system that comprises a microrobot couple, characterizing cooperative interactions, non-contact manipulation, and high cargo transport velocity is introduced. This microrobot couple can switch between capture and release states, facilitating effective cooperation. Using these capabilities, targeted drug delivery in a stomach model is conducted and performed the removal of uterine fibroids in a uterine model.


Abstract

Magnetic interfacial microrobots are increasingly recognized as a promising approach for potential biomedical applications ranging from electronic functionalization to minimally invasive surgery and targeted drug delivery. Nevertheless, existing research faces challenges, including less cooperative interactions, contact-based cargo manipulation, and slow transport velocity. Here, the cooperative magnetic interfacial microrobot couple (CMIMC) is proposed to address the above challenges. The CMIMC can be maneuvered by a single magnet and readily switched between capture and release states. By leveraging cooperative interactions and meticulous engineering of capillary forces through shape design and surface treatment, the CMIMC demonstrates the ability to perform non-contact cargo manipulation. Using the synergy of preferred magnetization directions and magnetic field distribution, along with optimization of the resistance-reducing shape, the CMIMC significantly enhances the cargo transport velocity, reaching 12.2 body length per second. The studies demonstrate various biomedical applications like targeted drug delivery and myomectomy, paving the way for the broad implementation of interfacial microrobots in biomedical fields.

Bollard‐Anchored Binder System for High‐Loading Cathodes Fabricated via Dry Electrode Process for Li‐Ion Batteries

Dry battery electrode (DBE) technology simplifies electrode production but relies on PTFE, which faces regulatory and performance challenges. The study introduces a “bollard hitch” dual-binder system using poly(acrylic acid)-grafted sodium carboxymethyl cellulose (PC) and minimal PTFE, reducing PTFE use by over 70%. This innovation enhances conductivity, flexibility, and mass loading, enabling sustainable, high-performance battery production.


Abstract

The dry battery electrode (DBE) process offers significant advantages over conventional wet-coating methods for electrode fabrication. Unlike traditional processes that rely on toxic solvents such as N-methyl-2-pyrrolidone (NMP), the DBE technique uses solvent-free methods, reducing environmental impact and production costs while enhancing compatibility and performance. However, polytetrafluoroethylene (PTFE), the only binder currently used for large-scale DBE fabrication (binder fibrillation), faces potential regulatory restrictions under Polyfluoroalkyl Substances (PFAS) guidelines and limits Li-ion conductivity, elastomeric properties, and particle adhesion. This study explores a novel dual-binder system, termed the “bollard hitch” model, designed to overcome these limitations as the first PTFE-less binder for binder fibrillation. Poly(acrylic acid)-grafted sodium carboxymethyl cellulose (PC) acts as the “bollard,” strongly attaching to the PTFE “anchor.” This binder system reduces PTFE usage by over 70% and enables the fabrication of high-mass loading cathodes (up to 90 mg cm− 2, 15.6 mAh cm− 2) with superior performance. It enhances ionic conductivity and mechanical strength, making it suitable for high-voltage applications and offering great potential to revolutionize the manufacturing of high-performance, durable energy storage systems.

Dual‐Gradient Silk‐Based Hydrogel for Spatially Targeted Delivery and Osteochondral Regeneration

A dual-gradient silk-based hydrogel is developed via an electric-field-driven method to enhance osteochondral regeneration. By integrating biomechanical and biochemical gradients, the hydrogel mimics native tissue architecture, directing site-specific cell differentiation. Encapsulated TGF-β1 nanocapsules ensure sustained release, promoting cartilage formation and subchondral bone remodeling, demonstrating its potential for regenerative medicine and targeted therapies.


Abstract

Contemporary clinical interventions for cartilage injuries focus on symptom management through pharmaceuticals and surgical procedures. Recent research has aimed at developing innovative scaffolds with biochemical elements, yet challenges like inadequate targeted delivery and reduced load-bearing capacity hinder their adoption. Inspired by the spatial gradients of biophysical and biochemical cues in native osteochondral tissues, a silk-based hydrogel that facilitates spontaneous dual-gradient formation, including mechanical gradients and growth factor gradients, for tissue regeneration, is presented. Driven by an electrical field, the hydrogel transitions from stiff to soft along the anode-to-cathode direction, mimicking the anisotropic structure of natural tissues. Simultaneously, incorporated growth factors encapsulated by charged monomers migrate to the cathode region, creating another parallel gradient that enables their sustained release. This design maintains bioactivity and enhances programmable growth factor concentration in the defect environment. In a rabbit model with full-thickness osteochondral defects, the dual-gradient hydrogel demonstrates significant potential for promoting osteochondral regeneration, offering a promising tool for clinical translation.

Fully Field‐Free Spin‐Orbit Torque Switching Induced by Spin Splitting Effect in Altermagnetic RuO2

This study reports robust, 100% field-free spin-orbit torque (SOT) switching in a RuO2(101)/[Co/Pt]2/Ta structure. Z-polarized spins generate out-of-plane anti-damping torque, enabling deterministic switching without an external magnetic field. The altermagnetic spin splitting effect (ASSE) in RuO2 enhances anisotropic spin current generation, demonstrating the potential of RuO2 as an efficient spin current source.


Abstract

Altermagnetism, a newly identified class of magnetism blending characteristics of both ferromagnetism and antiferromagnetism, is emerging as a compelling frontier in spintronics. This study reports a groundbreaking discovery of robust, 100% field-free spin-orbit torque (SOT) switching in a RuO2(101)/[Co/Pt]2/Ta structure. The experimental results reveal that the spin currents, induced by the in-plane charge current, flow along the [100] axis, with the spin polarization direction aligned parallel to the Néel vector. These z-polarized spins generate an out-of-plane anti-damping torque, enabling deterministic switching of the Co/Pt layer without the necessity of an external magnetic field. The altermagnetic spin splitting effect (ASSE) in RuO2 promotes the generation of spin currents with pronounced anisotropic behavior, maximized when the charge current flows along the [010] direction. This unique capability yields the highest field-free switching ratio, maintaining stable SOT switching even under a wide range of external magnetic fields, demonstrating exceptional resistance to magnetic interference. Notably, the ASSE-dominated spin current is found to be most effective when the current is aligned with the [010] direction. The study highlights the potential of RuO2 as a powerful spin current generator, opening new avenues for advancing spin-torque switching technologies and other cutting-edge spintronic devices.

Robust Full‐Surface Bonding of Substrate and Electrode for Ultra‐Flexible Sensor Integration

A direct hybrid bonding method that enables both gold and parylene bonding without adhesives is developed. This technique achieves full-surface direct bonding of electrodes and substrates in flexible electronic connections. The method offers high flexibility, stable mechanical durability, and high-resolution interconnections, accommodating varying electrode shapes and sizes in flexible electronic applications.


Abstract

The integration of multiple flexible electronics is crucial for the development of ultra-flexible wearable and implantable devices. To fabricate an integrated system, robust and flexible bonding throughout the connection area, irrespective of the electrode or substrate, is needed. Conventional methods for flexible direct bonding have primarily been confined to metal electrodes or substrate-only bonding due to varying material properties. Consequently, the mechanical and electrical properties of the connections deteriorate based on their shape and size. This study introduces a bonding technique for wearable electronics, achieving strong, flexible connections between materials like gold and parylene at a low temperature (85 °C). This hybrid direct bonding method ensures strong bonding across both the Au electrode and parylene substrate within electronic interconnections. Additionally, a 3D-stacked flexible structure that maintains robustness and high flexibility without an adhesive layer is successfully developed. An ultrathin photoplethysmography sensor developed by stacking an ultrathin organic photodetector atop an organic light-emitting diode is demonstrated. Unlike traditional methods requiring adhesives or high pressure, this approach maintains flexibility essential for deformation, withstanding bending at a radius of 0.5 mm. The technique's robustness suggests promising applications in durable, ultra-flexible electronics integration.

Stochastically Broken Inversion Symmetry of Van der Waals Topological Insulator for Nanoscale Physically Unclonable Functions

vdW Janus topological insulator is presented with stochastic inversion asymmetry via penetrative single-step plasma sulfurization, which enables the large-scale synthesis, one-step process, and low-temperature condition with back-end-of-line process compatibility. Sulfur dominance and its corresponding spatial OOP domain distribution are spatially observed using piezoelectric force microscopy hysteresis mapping, cross-sectional transmission electron microscopy, top-view scanning electroc microscopy, Kelvin probe force microscopy, and force-distance curve mapping. This provides an extendable synthetic solution for stochastic and size-controllable challenge-response pairs generation for PUFs application, which can overcome the conventional limitations of encryption technology.


Abstract

Owing to the exotic state of quantum matter, topological insulators have emerged as a significant platform for new-generation functional devices. Among these topological insulators, tetradymites have received significant attention because of their van der Waals (vdW) structures and inversion symmetries. Although this inversion symmetry completely blocks exotic quantum phenomena, it should be broken down to facilitate versatile topological functionalities. Recently, a Janus structure is suggested for asymmetric out-of-plane lattice structures, terminating the heterogeneous atoms at two sides of the vdW structure. However, the synthesis of Janus structures has not been achieved commercially because of the imprecise control of the layer-by-layer growth, high-temperature synthesis, and low yield. To overcome these limitations, plasma sulfurization of vdW topological insulators has been presented, enabling stochastic inversion asymmetry. To take practical advantage of the random lattice distortion, physically unclonable functions (PUFs) have been suggested as applications of vdW Janus topological insulators. The sulfur dominance is experimentally demonstrated via X-ray photoelectron spectroscopy, hysteresis variation, cross-sectional transmission electron microscopy, and adhesion energy variation. In conclusion, it is envisioned that the vdW Janus topological insulators can provide an extendable encryption platform for randomized lattice distortion, offering on-demand stochastic inversion asymmetry via a single-step plasma sulfurization.

Ultrafast Charge Transfer on Ru‐Cu Atomic Units for Enhanced Photocatalytic H2O2 Production

[Ru(bpy)2]2+ photosensitive components are integrated into the Cu-HHTP MOF, coordinating with the Cu-O4 sites to assemble a bi-functional unit, thereby facilitating efficient local electron migration. Compared to the dissociative photosensitizer system, this newly constructed configuration exhibits a significant increase in the efficiency of photoinduced charge carrier transfer, resulting in a 37.2-fold enhancement in the photosynthesis of H2O2.


Abstract

Photosensitizer-assisted photocatalytic systems offer a solution to overcome the limitations of inherent light harvesting capabilities in catalysts. However, achieving efficient charge transfer between the dissociative photosensitizer and catalyst poses a significant challenge. Incorporating photosensitive components into reactive centers to establish well-defined charge transfer channels is expected to effectively address this issue. Herein, the electrostatic-driven self-assembly method is utilized to integrate photosensitizers into metal–organic frameworks, constructing atomically Ru-Cu bi-functional units to promote efficient local electron migration. Within this newly constructed system, the [Ru(bpy)2]2+ component and Cu site serve as photosensitive and catalytic active centers for photocarrier generation and H2O2 production, respectively, and their integration significantly reduces the barriers to charge transfer. Ultrafast spectroscopy and in situ characterization unveil accelerated directional charge transfer over Ru-Cu units, presenting orders of magnitude improvement over dissociative photosensitizer systems. As a result, a 37.2-fold enhancement of the H2O2 generation rate (570.9 µmol g−1 h−1) over that of dissociative photosensitizer system (15.3 µmol g−1 h−1) is achieved. This work presents a promising strategy for integrating atomic-scale photosensitive and catalytic active centers to achieve ultrafast photocarrier transfer and enhanced photocatalytic performance.

All‐Solid‐State Lithium Metal Batteries with Microdomain‐Regulated Polycationic Solid Electrolytes

Analogic to the design of an anionic framework for inorganic sulfide/oxide solid electrolytes, a copolymeric polycationic electrolyte, P(AT-MBA-6F), that leverages the polycationic backbones with fluorinated microdomain trapping effect is constructed, which enables stable, fast and high-energy all-solid-state LMBs at ambient temperature.


Abstract

Solid polymer electrolytes (SPEs) are promising for high-energy and high-safety solid-state lithium metal batteries (LMBs). Here, a polycationic solid electrolyte (PCSE) is described that leverages the inherent high thermal/chemical stability of the polycationic domain and the anion trapping (FMAT) effect of another fluorinated microdomain for stable and fast-charging high-voltage LMBs. Specifically, while the polycationic imidazolium backbone ensures high segmental flexibility facilitating the Li+ mobility, the fluorinated microdomain effectively traps the bis(trifluoromethanesulfonyl)imide anions by strong dipole interactions, imparting localized solvation and restricted mobility of the anions, as well as improved oxidation stability. As a result, the PCSE exhibits a high ionic conductivity of 1.4 mS cm−1, a high Li+ transference number of 0.50, and a wide electrochemical window of ∼5.5 V at 25 °C. By way of in situ thermal polymerization of the electrolyte within assembled cells, the PCSE enables ultra-stable cycling of Li|LiNi0.8Co0.1Mn0.1O2 cells with a capacity retention of 98.1% after 500 cycles at 0.2 C at ambient temperatures. The work on the molecular design of PCSEs represents a fundamentally unique perspective for the rational design of SPEs with balanced properties that are historically challenging for high-energy, long-life, ambient-temperature solid-state LMBs.

Magnetic order as a tuning knob for Coulomb correlation

http://feeds.nature.com/nmat/rss/current - Wed, 19/02/2025 - 00:00

Nature Materials, Published online: 19 February 2025; doi:10.1038/s41563-025-02122-z

Antiferromagnetic order blocks interlayer hopping of electron–hole pairs in a two-dimensional magnetic semiconductor, leading to the formation of a type of optical excitation — magnetic surface excitons — with quasi-one-dimensional quantum confinement.

Magnetically confined surface and bulk excitons in a layered antiferromagnet

http://feeds.nature.com/nmat/rss/current - Wed, 19/02/2025 - 00:00

Nature Materials, Published online: 19 February 2025; doi:10.1038/s41563-025-02129-6

The emergence of magnetically confined surface excitons enabled by antiferromagnetic spin correlations is reported, which leads to the confinement of excitons to the surface of layered antiferromagnet CrSBr.

Controlling Coulomb correlations and fine structure of quasi-one-dimensional excitons by magnetic order

http://feeds.nature.com/nmat/rss/current - Wed, 19/02/2025 - 00:00

Nature Materials, Published online: 19 February 2025; doi:10.1038/s41563-025-02120-1

The antiferromagnetic-to-paramagnetic phase transition in a two-dimensional semiconducting magnet, CrSBr, induces an exciton confinement transition from a strongly bound quasi-one-dimensional state to a weakly bound interlayer-delocalized state.

Fri 21 Feb 16:00: Robust estimates of theoretical uncertainties at fixed-order in perturbation theory

http://talks.cam.ac.uk/show/rss/5408 - Tue, 18/02/2025 - 16:08
Robust estimates of theoretical uncertainties at fixed-order in perturbation theory

Precision computations for standard candle processes are a staple of the physics programme at colliders such as the Large Hadron Collider (LHC). The highest precision can be achieved in perturbative computations. In perturbation theory, however, calculations truncated at a fixed order inevitably have inherent theoretical uncertainty. This uncertainty quantifies the contributions from the missing higher-order terms (MHOU) that have not been accounted for. Traditionally, scale variation has been employed to estimate this uncertainty. In this talk, I introduce a straightforward yet effective prescription to directly incorporate these missing higher-order terms through theory nuisance parameters (TNPs). By varying these parameters, the associated uncertainty can effectively be estimated.

I will elaborate on how this methodology can be applied across various processes pertinent to LHC physics, specifically at next-to-leading (NLO) and next-to-next-to-leading order (NNLO) in perturbation theory. The findings reveal that in scenarios where scale variations yield consistent and reliable results, we can successfully mimic their outcomes using TNPs. Moreover, we will observe a considerable improvement in scenarios where traditional scale variation methods tend to underestimate the uncertainty involved.

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Tue 18 Feb 13:30: AI for better brain and mental health

http://talks.cam.ac.uk/show/rss/5408 - Tue, 18/02/2025 - 15:30
AI for better brain and mental health

Zoe Kourtzi is a Professor of Computational Cognitive Neuroscience at the University of Cambridge. Zoe’s research aims to develop predictive models of neurodegenerative disease and mental health with translational impact in early diagnosis and personalised interventions. Zoe received her PhD from Rutgers University and was a postdoctoral fellow at MIT and Harvard. She was a Senior Research Scientist at the Max Planck Institute for Biological Cybernetics and then a Chair in Brain Imaging at the University of Birmingham, before moving to the University of Cambridge in 2013. She is a Royal Society Industry Fellow, Cambridge University Lead at the Alan Turing Institute and Co-director of Cambridge’s Centre for Data Driven Discovery.’

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Tue 25 Feb 13:10: Exploring dietary behaviours, narratives and attitudes in Cambridge colleges

http://talks.cam.ac.uk/show/rss/5408 - Tue, 18/02/2025 - 14:16
Exploring dietary behaviours, narratives and attitudes in Cambridge colleges

Global appetite for meat exerts a devastating toll on human and planetary health but also offers a unique opportunity to achieve both climate and health benefits through a reduction in consumption. The potential is reflected in multiple national and international policy recommendations, but the UK lags behind targets​. Urgent improvement is needed at scale and speed.

My research aims to contribute to knowledge around reduction in meat consumption by addressing the research question: what are the main barriers and levers to achieving reduction in meat consumption in Cambridge colleges? I recently surveyed Cambridge college users to explore attitudes and narratives around meat consumption, prevailing dietary habits, and key levers and barriers for meat reduction. The survey ran from the 16th of December 2024 to the 2nd of February 2025 and resulted in more than 56,000 data points from 849 responses – a response rate of approximately 3% of the entire University population. The survey data contains a highly representative sample drawn from significant contributions from all the 31 colleges, and students, staff, postdoctoral researchers, and fellows alike. My talk will reveal some of the interim findings from the survey and discuss what these could tell us about the challenges and opportunities involved in reducing meat consumption here in Cambridge.

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Fri 21 Feb 12:00: Assessing language-specific capabilities of LLMs: Lessons from Swedish NLP

http://talks.cam.ac.uk/show/rss/5408 - Tue, 18/02/2025 - 12:17
Assessing language-specific capabilities of LLMs: Lessons from Swedish NLP

Abstract: In this talk, I discuss benchmarking and interpreting large language models in the context of Swedish. I present a selection of work from my PhD thesis, which analyze LLMs Swedish-specific capabilities in different areas: English-Swedish language transfer, multi-task benchmarking on Swedish NLU and targeted analysis of a specific case of Swedish linguistic variation. I outline some of the challenges that arise when trying to assess the language-specific capabilities of LLMs, some lessons I’ve learned throughout from my work and give a future outlook.

Bio: Felix Morger is a software engineer and computational linguist based in Gothenburg, Sweden. He recently defended his PhD thesis, titled “In the minds of stochastic parrots: Benchmarking, evaluating and interpreting large language models”. His main research interests are in benchmarking and model interpretability of large language models with a large focus on Swedish.

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Thu 01 May 15:00: The Case for Decentralized Scheduling in Modern Datacenters

http://talks.cam.ac.uk/show/rss/5408 - Tue, 18/02/2025 - 11:41
The Case for Decentralized Scheduling in Modern Datacenters

Modern data centres serve as a backbone for executing diverse user workloads. The growing demand for their resources has led to high volumes of traffic, requiring clusters to operate at high utilization. In this talk, I shall detail how data centre schedulers, which are responsible for mapping workload tasks to resources, perform under such challenging conditions. I will present how centralized schedulers, while globally informed, do not scale well under high load since they generate a lot of network traffic when continuously transferring updated node data. Conversely, distributed schedulers scale well but lack a precise global view of cluster resources, leading to suboptimal task allocations. Consequently, these existing schedulers impose up to three times longer wait times on tail tasks, leading to large variance in inter-task start times, and hence, longer task and job completion times.

I will then describe recent advances in decentralized scheduling, focusing on performance, scalability, and load balancing. I will present our approach of job-aware decentralized scheduling which effectively reduces task wait times even under high cluster load. I will also talk about how distributed optimization algorithms can be implemented within the framework of decentralized scheduling, in order to provide theoretical guarantees for convergence to an optimal schedule. By the end of this talk, I hope to convince you that decentralized schedulers achieve a good balance in both scale and performance, and are indeed the most practical solution for data centres.

Bio: Smita Vijayakumar recently completed her PhD in Computer Science from the University of Cambridge, under the supervision of Evangelia Kalyvianaki. As a part of her thesis, she developed a decentralized scheduling framework to reduce tail task latencies in highly utilized datacenters. She has over twelve years of industry experience at companies like Cisco and Juniper, working on cloud computing, networking, and distributed systems. She also has an MS in Computer Science from The Ohio State University, where her work investigated cloud resource allocation to bottleneck stages for processing streaming applications. Her research has been published in top-tier ACM and IEEE conferences. She has also been actively involved in mentoring, teaching, and community leadership, including founding Women Who Go in India. Smita’s expertise spans cloud scheduling, resource management, and scalable distributed systems.

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Thu 20 Feb 17:00: Formalising Brauer Group and Group Cohomology in Lean4

http://talks.cam.ac.uk/show/rss/5408 - Tue, 18/02/2025 - 11:09
Formalising Brauer Group and Group Cohomology in Lean4

The concept of Brauer Groups, originally developed to classify division algebras, has now found many uses in scheme theory and class field theory. Brauer Groups over a field k is defined as the collection of central simple algebras over k modulo certain equivalence relations and this project is set out to formalise the correspondence between the Brauer groups and the second Galois cohomology groups Br(k) ≅ H²(Gal(k_sep/k) , k ⃰_sep). In this talk, we give a complete formalisation between the relative Brauer group of a finite dimensional field extension Br(K/k) and the second group cohomology H²(Gal (K/k) , K ⃰) as the first step.

=== Hybrid talk ===

Join Zoom Meeting https://cam-ac-uk.zoom.us/j/87143365195?pwd=SELTNkOcfVrIE1IppYCsbooOVqenzI.1

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We are hiring!

4 January 2021

We are seeking to hire a research assistant to work on carbon nanotube based microdevices. More information is available here: www.jobs.cam.ac.uk/job/28202/

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4 January 2021

We are seeking to hire a postdoc researcher to work on the structuring of Li-ion battery electrodes. More information is available here: www.jobs.cam.ac.uk/job/28197/