BRILLOUIN, ULTRAFAST AND TERAHERTZ SPECTROSCOPY OF MICRO- AND NANOSTRUCTURES, INCLUDING LIVING OBJECTS

• Alexandr V. Sadovnikov, Saratov State University (Russia) (sadovnikovav@gmail.com)
• Valery V.Tuchin, Saratov State University; Institute of Precision Mechanics and Control of RAS; Tomsk State University (Russia) (tuchinvv@mail.ru)

• Anna A. Manysheva, Saratov State University (Russia) (aamsgmaam2006@gmail.com) 
• Alexey A. Solyanov, Saratov State University (Russia) (solyanov555@gmail.com)

• Alexandra Kalashnikova, Ioffe Institute, St. Petersburg (Russia)
• Vladimir V. Ustinov, M.N. Mikheev Institute of Metal Physics, UB RAS (Russia)
• Dmitry Gorin, Center of photonics science and engineering (Russia)
• Ansar R. Safin, Kotelnikov Institute of Radio-Engineering and Electronics, RAS (Russia)
• Valentin Milichko, New Uzbekistan University(Uzbekistan)
• Vladislav Yakovlev, Texas A&M University (USA)
• Alexandr S. Samardak, Far Eastern Federal University (Russia)
• Alexey B. Ustinov, St. Petersburg Electrotechnical University “LETI” (Russia)
• Yuri. V. Khivintsev, Kotelnikov Institute of Radioengineering and Electronics of RAS, Saratov Branch (Russia)

The main goal of the Track

The main goal of this track is to present and discuss recent advances in Brillouin, ultrafast, microwave and terahertz spectroscopy as powerful tools for probing dynamic, structural, and mechanical properties of micro- and nanoscale systems — ranging from artificial magnetic materials and metamaterials to living cells and soft matter.

Special attention will be paid to the development and application of Brillouin Light Scattering (BLS) spectroscopy for the study of spin-wave dynamics, magnon transport, and interfacial phenomena in magnetic thin films, multilayers, and patterned magnonic crystals. The track will also cover microwave (RF) spectroscopy techniques for characterizing magnetization dynamics, ferromagnetic resonance, and magnon-photon coupling in hybrid quantum-classical systems.

A key objective of the Ultrafast Spectroscopy component within this track is to elucidate the fundamental dynamic processes occurring in micro- and nanostructures on femtosecond and picosecond time scales. The focus lies on utilizing ultrashort laser pulses to probe and control non-equilibrium states of matter, revealing transient interactions between electronic, spin, lattice, and mechanical degrees of freedom.

Terahertz spectroscopy will be discussed as a unique approach for accessing low-energy excitations, carrier dynamics, and collective modes in condensed matter, including topological insulators, 2D materials, and bio-molecular assemblies. The interplay between THz fields and magnetic order, as well as ultrafast optical control of spin and lattice degrees of freedom, will be among the key topics.

Beyond magnetic and electronic systems, the track emphasizes the growing role of Brillouin and related mechanical spectroscopy methods in quantifying elastic properties, viscoelastic response, and micromechanical stiffness in soft matter, biomaterials, and living objects — from single cells and tissues to engineered hydrogels and organ-on-chip platforms.

On this basis, the track will analyze emerging hybrid and multimodal approaches combining optical, microwave, and terahertz probes for:

Non-invasive, label-free characterization of mechanical and magnetic properties at the micro- and nanoscale;

Mapping of spin-wave propagation, damping, and nonlinear interactions in magnonic devices;

Probing cell mechanics, tissue elasticity, and mechanobiological responses in health and disease;

Development of novel sensors, information-processing elements, and quantum interfaces based on magnonic, phononic, and photonic excitations.

Both fundamental studies and applied research will be welcomed, with a focus on cross-disciplinary synergy between condensed matter physics, photonics, biophysics, and materials science.

Topics:

• Brillouin Light Scattering (BLS) spectroscopy: theory, instrumentation, and data analysis
• Micro- and nano-focused Brillouin microscopy for spatially resolved mechanical mapping
• Time-resolved and pump-probe Brillouin spectroscopy of dynamic processes
• Spin-wave spectroscopy and magnon dynamics in ferromagnetic, antiferromagnetic, and multiferroic nanostructures
• Microwave and RF spectroscopy of magnetization dynamics: FMR, VNA-FMR, and cavity magnonics
• Magnon-photon and magnon-phonon coupling in hybrid quantum-classical systems
• Terahertz time-domain spectroscopy of magnetic, topological, and low-dimensional materials
• Ultrafast optical control of spin, charge, and lattice dynamics in condensed matter
• Coherent phonon generation and hypersound spectroscopy at the nanoscale
• Non-equilibrium carrier and exciton dynamics in semiconductors and 2D materials probed by ultrafast methods
• Brillouin and mechanical spectroscopy of soft matter: elasticity, viscosity, and microrheology
• Label-free biomechanical imaging of cells, tissues, and biomaterials via Brillouin shifts
• Quantification of tissue stiffness and viscoelastic properties in health and disease
• Ultrafast probing of intracellular dynamics and mechanobiological responses
• Terahertz spectroscopy of biomolecules, hydrated systems, and biological tissues
• Hybrid multimodal approaches: combining Brillouin, THz, ultrafast optical, and microwave probes
• Topological and non-reciprocal excitations studied by Brillouin and THz techniques
• Interfacial phenomena and strain-mediated coupling in heterostructures (YIG/semiconductor, YIG/graphene, piezo/magnet)
• Electric-field and strain control of Dzyaloshinskii–Moriya interaction and magnetic anisotropy
• Nonlinear and parametric effects in magnonic and phononic systems probed by spectroscopic methods
• Machine learning and advanced signal processing for spectroscopic data analysis
• Development of compact, fiber-integrated, and on-chip Brillouin/THz sensors
• Applications in magnonic computing, signal processing, and quantum information interfaces
• Optical and opto-acoustic techniques for mechanobiology and tissue engineering
• Correlative spectroscopy: linking mechanical, magnetic, and optical properties in complex systems