Quantum memories
Rare-earth-doped bulk crystals with long-lived optical and spin coherences for quantum memories designed to support long-distance quantum communication.
Bulk crystals · Coherent spectroscopyInstitut de Recherche de Chimie Paris CNRS · Chimie ParisTech – PSL
Crystals and Quantum State Dynamics (CQSD)
Crystalline matter
for lasting quantum states.
Crystals and Quantum State Dynamics (CQSD) is an academic research group at the Paris Institute for Chemical Research (IRCP), affiliated with CNRS, Chimie ParisTech and PSL University. We design, grow and study quantum-grade crystalline materials—from bulk crystals to nanostructures—and explore their integration into photonic and sensing devices.
BulkThin filmNanocrystal
A shared scientific vision
From materials chemistry
to quantum function.
CQSD brings together crystal growth, materials science, optical spectroscopy and quantum physics. Our shared goal is to create solid-state platforms in which fragile quantum states can be prepared, controlled and connected.
This integrated approach links the atomic-scale environment of quantum emitters to our progress towards their integration into photonic and sensing architectures.
Research
Across bulk crystals, thin films and nanoparticles.
Preserve coherence while making quantum states useful, addressable and ready to connect.
Hybrid quantum systems
Nanocrystals, thin films and molecular crystals designed to preserve quantum states while coupling efficiently to light.
Nano-optics · Light–matter interfaces
Quantum sensing
Diamond colour centres in thin films and nanoparticles for magnetic and pressure sensing.
Thin films · NanodiamondsOur approach
Built across disciplines.
One team connects every step, from the chemistry of a host material to the quantum behaviour of the emitters embedded within it.
- 01Design
Choose emitters, hosts and local environments.
- 02Grow
Create bulk crystals, films and nano-objects.
- 03Measure
Resolve optical and spin dynamics.
- 04Enable
Design materials for future integration into photonic architectures.
Research highlight · 2026
A crystal for future quantum memories.
Ytterbium-171 ions in calcium tungstate retain spin coherence for up to 0.15 seconds and can be controlled entirely with light, making the material a promising platform for future quantum memories.
People
A multi-PI research group.
CQSD is a multi-investigator environment where complementary expertise and shared experimental platforms create room for independent ideas.
Meet the complete team ↗
Principal investigator
Philippe Goldner
Research Director · CNRS
Philippe Goldner develops rare-earth-doped and hybrid crystalline materials for optical quantum technologies, from materials synthesis and coherent spectroscopy to quantum-state control. He coordinated the European NanoQTech project and received an ERC Advanced Grant in 2021. His distinctions include the CNRS Silver Medal and the Philippe A. Guye Prize of the French Academy of Sciences.
Principal investigator
Mary De Feudis
Associate Professor · CY Cergy Paris
Mary De Feudis joined IRCP in 2024. Trained through a double PhD in physics, nanoscience and materials science, she develops diamond materials from controlled synthesis through device integration. Her NanoG4V project focuses on nanodiamonds containing quantum-grade colour centres for magnetic-field detection under extreme pressure and temperature, nanoscale thermometry and bioimaging.
Principal investigator
Diana Serrano Garcia
Research Director · CNRS
Diana Serrano Garcia obtained her PhD from the University of Normandy in 2012. After postdoctoral research at Lund University and the University of Zürich, she joined IRCP as a CNRS researcher in 2016. Her work focuses on rare-earth materials for quantum technologies, combining materials development with the study and control of their optical and spin properties.
Principal investigator
Alexandre Tallaire
Research Director · CNRS
Alexandre Tallaire is a materials scientist specialising in quantum materials and diamond growth. After a PhD on diamond synthesis for power electronics and research roles at NTT and Aixtron, he joined CNRS in 2009 and IRCP in 2017. His work spans CVD growth, defect and impurity control, diamond colour centres, rare-earth ions and oxide thin films. In 2022, he co-founded HiQuTe Diamond.
Postdoctoral researchers
01Anatole BachRare-earth–diamond hybrid materials
02Yisheng LeiRare-earth molecular crystals
03Chloe NewsomShallow colour centres in diamond
04Idris TlemsaniRare-earth molecular crystals
05Karolina WaszkowskaCrystals for quantum memories
PhD students
01Suma Al-HunaishiRare-earth molecular crystals
02Joa Al YahyaRare-earth–diamond hybrid materials
03Alexandre HebbrechtRare-earth–diamond hybrid materials
04Diana KimNanophotonics
05Lingraj KumarNanodiamonds for quantum sensing
06Tianfang LiRare-earth-doped thin films
07Pengrui LiuCrystals for quantum memories and opto-mechanics
08Lucas Araujo Oliveira Sotero SilvaNanophotonics
Publications
Recent publications.
2026
Sub-second spin and lifetime-limited optical coherences in ¹⁷¹Yb³⁺:CaWO₄Tiranov et al. · Nature Communications
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2026Optically detected nuclear magnetic resonance of coherent spins in a molecular complexVasilenko et al. · Nature Materials
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2026Interactions in Rare-Earth-Doped Nanoparticles: A Multi-Transition, Concentration, and Excitation Path AnalysisPerrin et al. · ACS Nano
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2026Highly luminescent terbium-doped Y₂O₃ thin films via defect and valence state controlHebbrecht et al. · Optical Materials
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2025Individual solid-state nuclear spin qubits with coherence exceeding secondsO’Sullivan et al. · Nature Physics
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2025Incoherent Measurement of a Sub-10 kHz Optical LinewidthMontjovet-Basset et al. · Physical Review Letters
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2025Erbium-doped yttrium oxide thin films grown by chemical vapor deposition for quantum technologiesBlin et al. · Applied Physics Reviews
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2025Enhanced magnetic field sensitivity of shallow NV⁻ ensembles via high-temperature implantationAl Yahya et al. · Journal of Applied Physics
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Opportunities
Join CQSD.
We welcome researchers who want to develop ambitious work at the intersection of quantum science, photonics, chemistry and advanced materials.
Open position · Tenure track
Junior Professor Chair: Doped crystals for quantum nanophotonics
PSL University is recruiting in materials chemistry and/or physics for the NanoPhotQ project at IRCP. The position offers a reduced teaching load, competitive salary and start-up funding, with a pathway to a tenured professorship.
Contact ↗
Paris · France
