Institut 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.

Iridescent calcium tungstate crystal grown by CQSD
CaWO₄ single crystal · © Nolwenn Buvat
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.

01 Transparent europium-doped yttrium orthosilicate crystal
Eu³⁺:Y₂SiO₅ crystal© Nolwenn Buvat

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 spectroscopy
02 Iridescent rare-earth-doped yttrium oxide thin film on a partial wafer
Rare-earth-doped Y₂O₃ thin film© Nolwenn Buvat

Hybrid quantum systems

Nanocrystals, thin films and molecular crystals designed to preserve quantum states while coupling efficiently to light.

Nano-optics · Light–matter interfaces
03 Focused ion beam system used for diamond implantation
FIB system for diamond implantation© Nolwenn Buvat

Quantum sensing

Diamond colour centres in thin films and nanoparticles for magnetic and pressure sensing.

Thin films · Nanodiamonds

Our 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.

  1. 01Design

    Choose emitters, hosts and local environments.

  2. 02Grow

    Create bulk crystals, films and nano-objects.

  3. 03Measure

    Resolve optical and spin dynamics.

  4. 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.

Four-panel figure showing all-optical spin control, spin linewidth, spin coherence decay and its temperature dependence in ytterbium-doped calcium tungstate
Figure 2 · All-optical coherent spin control in ¹⁷¹Yb³⁺:CaWO₄. Tiranov et al., Nature Communications 17, 4115 (2026) · CC BY-NC-ND 4.0

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
Black-and-white portrait of Philippe Goldner
© Nolwenn Buvat

Principal investigator

Philippe Goldner

Research Director · CNRS

Philippe Goldner is a CNRS research director at the Paris Institute for Chemical Research (IRCP). His research focuses on rare-earth-doped and hybrid crystalline materials for optical quantum technologies, spanning materials development, coherent spectroscopy and quantum-state control. He coordinated the European FET-Open NanoQTech project and received an ERC Advanced Grant in 2021. His distinctions include the Stars of Europe award (2020), the CNRS Silver Medal (2022) and the Philippe A. Guye Prize of the French Academy of Sciences (2024).

Principal investigators

01Mary De FeudisAssociate Professor · CY Cergy Paris
02Philippe GoldnerResearch Director · CNRS
03Diana Serrano GarciaResearch Director · CNRS
04Alexandre TallaireResearch Director · CNRS

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.

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.

Application deadline30 September 2026
16:00 Paris time

Expected startJanuary 2027

View position & apply Official PSL posting · English
Contact Paris · France

Funding & partners.