Jayshree Dadheech from our laboratory recently attended the HarwellXPS Summer School 2026, held in Oxford, UK. The internationally attended summer school brought together researchers and delegates from across the world to explore the latest developments in X-ray Photoelectron Spectroscopy (XPS) and related techniques. The programme featured a series of insightful lectures covering both the fundamentals and advanced applications of XPS. The sessions included the Fundamentals of XPS by Arthur Graff (HarwellXPS) and Dr. Elisabetta Arca (University of Liverpool), Practical data analysis using CasaXPS by Dr. Neal Fairley (Casa Software Ltd), Valence band and UPS analysis by Prof. Robert Palgrave (HarwellXPS, University College London), Hard X-ray Photoelectron Spectroscopy (HAXPES) by Prof. Anna Regoutz (University of Oxford) along with several other expert lectures.

Eunjin Koh and Nick Barrett completed a hard X-ray photoelectron spectroscopy (HAXPES) experiment at the BL09XU beamline of the SPring-8 synchrotron (Sayo, Japan). The beamtime was dedicated to investigating the effect of the HfO₂/ZrO₂ laminate interface on the oxygen vacancy concentration.

The IEEE Eastern Europe Ferroelectric Symposium 2026 took place in Riga, Latvia, from June 1–4, 2026, attracting over 100 scientists worldwide. Organised by the Institute of Solid State Physics, University of Latvia, and sponsored by the IEEE UFFC Society, the programme featured 5 plenary talks, 22 invited lectures, 40 oral presentations, and 34 posters covering experimental and theoretical ferroelectrics research, with growing emphasis on AI and machine learning for microscopy and rapid materials discovery.

LENSIS Lab (SPEC, CEA Saclay) was well represented By Dr. Somnath Kale presenting his work on multilevel polarization switching in ferroelectric hafnium thin films and devices within the Ferro4EdgeAI framework.

L. Pérez Ramírez work on in situ HAXPES characterization of all-solid-state batteries (ASSBs) has just been published in Materials Today Communications. This article assesses the interfacial stability between β-Li3PS4 (LPS) solid state electrolyte and deposited lithium metal using in situ hard X-ray photoemission spectroscopy (HAXPES) approach. We show that the introduction of a 4 nm-thick Al₂O₃ interlayer grown by Atomic Layer Deposition (ALD) enhances the interfacial stability by mitigating undesirable side reactions. By comparing the two systems, LPS /Li and LPS/Al₂O₃/Li, we highlight the importance of interface engineering in solid-state batteries, particularly through protective coatings like Al₂O₃ made by ALD, which can enhance the stability of sulfide-based solid electrolytes against lithium metal.

Congratulations to our former PhD student, Tom Iung, for having successfully defending his thesis the past 21 of April. His subject based on “Hafnia-based ferroelectric field-effect transistor stacks: correlations between physical properties and device performances” was conjointly supervised by Nick Barrett (CEA) and Mickael Gros-Jean (STMicroelectronics). The discussions with a highly distinguished international jury were certainly fruitful and they contribute to the rigorousness of the work in our team.

The Novel High-k workshop (https://www.namlab.com/high-k-workshop-2026-march-24-25th) was held from March 24^th to 26^th at NaMLab in Dresden, Germany. The 20^th anniversary of the discovery of ferroelectric doped HfO₂ was celebrated by 36 oral presentations, ranging from theoretical and experimental studies on ferroelectricity in HfO₂ to device applications of ferroelectric doped HfO₂.

‍This year over 14000 scientists came together for the APS Global Physics summit held in Denver, Colorado, USA from 15^th-19^th March 2026 (https://summit.aps.org/).

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Determination of the oxygen vacancy (V_O) distribution within ultra-thin film ferroelectric hafnia (HfO2)-based devices is crucial to engineering optimal properties for non-volatile memory and logic devices. So far, x-ray photoelectron spectroscopy (XPS) combined with Ar⁺ ion sputtering has been the predominantly used approach for quantifying the V_O concentration. Here, we show that using Ar⁺ ion sputtering to depth-profile the hafnia-based film affects film chemistry and can introduce errors in V_O estimation by up to an order of magnitude.

As a result, the method should be approached with more caution. This paper demonstrates that non-destructive, hard x-ray photoemission (HAXPES) using synchrotron radiation ought to be favored. In addition, we show that reliable, quantitative evaluation of the physical chemistry is compromised by surprising and commonplace mistakes in parameters used for Hf 4f core-level spectral analysis. Third, a widespread assignation of one of the O 1s core-level peak components to the presence of V_O is erroneous and leads to further errors in the measurement of V_O concentration. The conclusions are supported by careful comparison between XPS and HAXPES experimental results and first principles calculations. We provide clear indications for reliable analysis and interpretation of the photoemission data, which should allow progress in materials engineering of ferroelectric devices.