PhD (M/F) - Designing plasmonic liquid crystals

CNRS; France; Sur place; EUR 27 000 - 38 000; Plein temps

Avantages offerts par ce poste

Training provided

Onboarding support

Social benefits

Résumé du poste

CNRS's Laboratoire de Physique des Solides (LPS) in Orsay, France, invites applications for a First Stage Researcher (R1) position in the MATRIX team. The project focuses on plasmonic colloidal liquid crystals and soft matter, with emphasis on nanorod synthesis, optical properties, and phase behavior.

Starting date 1 January 2027; 35 hours per week; fixed-term contract. The successful candidate will work in a vibrant, international environment, benefit from comprehensive training, onboarding

Qualifications

• Background in chemistry (nanosynthesis) or physics (plasmonics, optics).
• Excellent communication skills in English; knowledge of French is not mandatory.

Connaissances

Excellent communication skills

English proficiency

Description du poste

Organisation/Company CNRS Department Laboratoire de Physique des Solides Research Field Physics Researcher Profile First Stage Researcher (R1) Application Deadline 22 Oct 2026 - 23:59 (UTC) Country France Type of Contract Temporary Job Status Full-time Hours Per Week 35 Offer Starting Date 1 Jan 2027 Is the job funded through the EU Research Framework Programme? Not funded by a EU programme Is the Job related to staff position within a Research Infrastructure? No

Offer Description

The Laboratoire de Physique des Solides (LPS) is a joint research unit (UMR 8502) of Université Paris-Saclay and the CNRS. It is affiliated with the CNRS Institute of Physics and with Section 28 of the French National Council of Universities (Conseil National des Universités). The LPS is a member of the Friedel-Jacquinot Federation, a structure coordinating physics research on the Moulon campus in Orsay (Île-de-France). The laboratory brings together around one hundred researchers and faculty members, both experimentalists and theoreticiens, whose research activities are supported by approximately sixty engineers, technicians, and administrative staff.
Each year, the laboratory welcomes a large number of undergraduate and graduate students, including many PhD students, as well as postdoctoral researchers and visiting scientists. The laboratory covers a broader range of topics than its name might suggest and aims to address the full diversity of condensed matter physics. Research activities are organized around three main themes, each involving approximately the same number of scientists:

• New electronic states of matter
• Physical phenomena at reduced dimensions
• Soft matter and the physics-biology interface

The first research theme brings together experimental and theoretical studies of systems in which electronic correlations are generally strong and which exhibit remarkable properties and unconventional electronic states, such as superconductivity, magnetism, and metal-insulator transitions.
The second theme encompasses activities broadly falling within the field of nanoscience. These are investigated from the perspective of fundamental properties, particularly when the dimensions of an object become comparable to characteristic physical length scales, such as the coherence length or mean free path.
The third theme extends the concept of soft matter to biological systems. Research topics therefore range from complex systems to living tissues, and from liquid crystals to foams, including polymers and granular systems. These studies lie at the interface between physical chemistry and biology.
The research will be carried out within the MATRIX team at the Laboratoire de Physique des Solides (CNRS-UMR 8502). This research project is funded by the French National Research Agency (ANR) through the MOST project.

Working conditions and benefits

• Annual leave and RTT: 44 days per year
• Transportation: reimbursement of 75% of transportation costs and a sustainable mobility allowance of up to €300
• Parental support: access to childcare places, CESU vouchers and co-funded holiday vouchers, support for after-school childcare, allowance for parents of children with disabilities, and administrative subsidies (leisure centers, holiday centers, school trips, etc.)
• Training: training provided upon taking up the position and throughout your career
• Integration: support during the onboarding and transition into the position
• Social benefits: contribution to supplementary health insurance, subsidized collective catering, sports and leisure activities, ticketing services, and other benefits

Context.

Colloids and liquid crystals are two pillars of soft-matter science, but they are rarely combined. Yet, their combination offers unique opportunities, as colloidal self-organization can create artificial materials with emergent, tunable properties. Unlike approaches where colloids act as dopants in molecular liquid crystals, anisotropic colloids, such as nanorods, can form liquid-crystalline phases on their own. These colloidal liquid crystals (CLCs) are lyotropic, with phases ranging from nematic to smectic as the concentration increases. Compared to molecular systems, CLCs are slow, tunable, and accessible to imaging and single-particle tracking, enabling direct observation of their dynamics. They thus serve both as versatile model systems and as platforms for functional materials, with applications in structural colors or polarized light emission.
Scientific project. This project explores a new direction: plasmonic CLCs based on gold and silver nanorods and is structured around three objectives. First, we will establish the morphogenesis of plasmonic CLCs by synthesizing nanorods with controlled aspect ratios and cross-sectional geometries. Combined with simulations, this will identify the conditions for targeted mesophases and clarify how particle shape influence ordering. Second, we will develop multi-responsive CLCs whose structure and properties can be tuned by electric and magnetic fields, light, temperature, or chemical environment. A key goal is to demonstrate reversible, light-induced phase transitions driven by plasmonic photothermal effects, where resonant excitation locally modifies interparticle interactions. Experiments and modeling will establish a predictive link between nanoscale interactions and macroscopic phase behavior. Third, we will connect structure, dynamics, and optical response using optical microscopy, Small Angle X-ray scattering, computer simulations, and spectroscopy. We will probe anisotropic diffusion and ordering in different phases, and relate these to optical properties. Aligned CLC domains are expected to exhibit strong linear dichroism and polarization-dependent plasmonic shifts due to interparticle coupling while cholesteric phase would also display circular dichroism. In addition, the intrinsic periodicity of cholesteric and smectic phases may enable selective Bragg reflection, opening new regimes of plasmonic–photonic coupling and tunable structural color.
Overall, this project will establish plasmonic CLCs as a new class of reconfigurable metamaterials with programmable optical functionalities. While largely curiosity-driven, this work lays the foundation for future applications in stimuli responsive photonic devices, addressing both fundamental challenges and emerging societal needs.

Requested profile:

We are looking for a candidate with a background in chemistry (nanosynthesis) or physics (plasmonics, optics). Excellent communication skills (written and oral) in English are expected. Knowledge of French is not mandatory.