TeraHertz detection enabled by mOleculaR optomechanics

About project


The generation, manipulation and detection of electromagnetic waves across the entire frequency spectrum is the cornerstone of modern technologies, underpinning wide disciplines across sensing, imaging, spectroscopy and data processing, amongst others. Whilst the last century has witnessed an impressive evolution in devices operating at frequencies either below 0.1 THz (microwave and antenna technology) or above 50 THz (near-infrared and visible optical technology), in between the lack of suitable materials and structures for efficient electromagnetic manipulation has resulted in the so-called “THz gap” : a band of frequencies in the 0.3 – 30 THz region of the spectrum for which compact and cost-effective sources and detectors do not exist – even though their application has enormous potential in medical diagnostics, security, astronomy, and wireless communication.

In this project, we will demonstrate the first nano-scale, cost-effective, fast and low-noise detector working at room temperature in the 1 – 30 THz range by developing a radically new concept of signal up-conversion to visible/near-infrared (VIS/NIR) radiation, leveraging the latest scientific breakthroughs in the new scientific field of molecular cavity optomechanics. In particular, we will design and synthesize molecules with both large IR and Raman vibrational activity in that THz range to be integrated into plasmonic nano- and pico-cavities so that their vibration mediates the coherent transfer of energy from the THz to the laser signal driving the cavity. In our approach, we will also employ THz antennas to improve the coupling efficiency of the THz field to the molecules.

This bold vision, which builds on the fundamentals of light-matter interaction (science) and converges toward the on-chip integration in a silicon-compatible chip (technology), completely surpasses any previous technological paradigms related to the measurement of THz molecular vibration as well as its possible manipulation.

Fact Sheet

Project ID
EU Contribution
EUR 3,274,122.5
Total Cost
EUR 3,274,122.5
Call for Proposal
Term of completion


Universitat Politècnica de València (UPV), Spain (Coordinator)
Plasmonic Metamaterials - Leader: Alejandro Martínez
Nanophotonics Technology Center - Leader: Alejandro Martínez
Stichting Nederlandse Wetenschappelijk Onderzoek Instituten (AMOLF), The Netherland
Resonant Nanophotonics Group - Leader: Femius Koenderink
Photonic Forces Group - Leader: Ewold Verhagen
King's College London (KCL), United Kingdom
Rosta research Group - Leader: Edina Rosta
The Chancellor Masters and Scholars of the University of Cambridge (UCAM), United Kingdom
Nanophotonics Centre - Leader: Jeremy Baumberg
Agencia Estatal Consejo Superior de Investigaciones Científicas (CSIC), Spain
Theory of Nanophotonics Group - Leader: Javier Aizpurúa
Ecole Polytechnique Federale de Lausanne (EPFL), Switzerland
Laboratory of Quantum Nano-optics - Leader: Christophe Galland
Laboratory of Photonics and Quantum Measurements - Leader: Tobias Kippenberg
Lytid Sas (LYT), France
Leader: Pierre Gellie

THOR's Vision

The overall objective of THOR is to demonstrate a compact, on-chip, CW-laser-driven THz detector with ultrafast response and excellent NEP using optomechanically-controlled molecular vibrations in a plasmonic cavity.

To this end, the following specific objectives will be pursued:

  1. Designing and synthesizing molecules with strongly infrared and Raman-active vibrational resonances in the 1-30 THz range.
  2. Building cavities with optical Q factors > 10^3, mode volumes ∼λ^3/10^4, molecular vacuum coupling rate g0/2π >> 1 GHz, integrated with THz antennas.
  3. Establishing coherent interactions of both light and THz radiation with molecular vibrations, demonstrating dynamical backaction state conversion with effective cooperativity C > 1.
  4. Experimental demonstration and characterization of a room-temperature, low-noise, coherent THz-to-optics converter on a silicon chip.

THOR’s device: a plasmonic nano- or pico-cavity loaded with a molecular ensemble is integrated into a silicon nitride waveguide. THz antennas increase the collection efficiency. THz-shifted Vis/NIR light can be efficiently detected with ultra-low noise using standard equipment.

This section will be completed with project results.


European Commission’s Innovation Radar highlights THOR Project's excellent innovations

European Commission’s Innovation Radar highlights THOR Project's excellent innovations

These innovations have been jointly developed by several members of the THOR Consortium.

More information can be found here:


Cadena SER - La UPV desarrolla una herramienta para facilitar la detección de explosivos o drogas

Cadena SER - La UPV desarrolla una herramienta para facilitar la detección de explosivos o drogas collects an article on the Thor project:
Link to article recoge una artículo sobre el proyecto Thor:

Kick-off Meeting of the THOR project

Kick-off Meeting of the THOR project

March 12-13, 2019: The Kick-off Meeting of the THOR project was held in Amsterdam (The Netherlands) at the premises of partner AMOLF.

Thanks to F. Koenderink and Ewold Verhagen for a great organization. We had a very successful meeting, plenty of interesting scientific dicussion. Just the first step towards a successful project!

2nd project meeting in San Sebastián (Spain)

2nd project meeting in San Sebastián (Spain)

October 20-11, 2019: The 2nd Meeting of the THOR project was held in San Sebastián (Spain) at the premises of partner CSIC. We had a lot of interesting scientific discussions which will contribute to the success of the project.

Thanks to J. Aizpúrua, R. Esteban and colleagues for a great organization in a wonderful place.


T. Neuman, R. Esteban, G. Giedke, M. K. Schmidt, and J. Aizpurua, “Quantum description of surface-enhanced resonant Raman scattering within a hybrid-optomechanical model,” Physical Review A 100, 043422, 2019. (link)

J. Losada, A. Raza, S. Clemmen, A. Serrano, A. Griol, R. Baets and A. Martínez, “SERS detection via individual bowtie nanoantennas integrated in Si3N4 waveguides,” IEEE Journal of Selected Topics in Quantum Electronics. 25(3), 4600806, 2019. (link).

T. Neuman, J. Aizpurua, R. Esteban, «Quantum theory of surface-enhanced resonant Raman scattering (SERRS) of molecules in strongly coupled plasmon–exciton systems», Nanophotonics, 9,  2, pp. 295 – 308, 2020. (link)

A. Pereverzev, Z. Koczor-Benda, E. Saparbaev, V. Kopysov, E. Rosta, O. Boyarkin, «Spectroscopic Evidence for Peptide-Bond-Selective Ultraviolet Photodissociation», The Journal of Physical Chemistry Letters, 11, 1, 206–209, 2019 (link)

T. Neuman, R.Esteban, G.Giedke, M. Schmidt, J. Aizpurua, «Quantum description of surface-enhanced resonant Raman scattering within a hybrid-optomechanical model», Physical Review A, 100, 043422,,2019. (link).

Y. Zhang, J. Aizpurua, R. Esteban, «Optomechanical Collective Effects in Surface-Enhanced Raman Scattering from Many Molecules», ACS Photonics, 7, 7, 1676–1688, 2020. (link)

F. Ojambati, W. Deacon, R. Chikkaraddy, C. Readman, Q. Lin, Z. Koczor-Benda, E. Rosta, O. Scherman, J. Baumberg, «Breaking the Selection Rules of Spin-Forbidden Molecular Absorption in Plasmonic Nanocavities», ACS Photonics(9), 2337-2342, 2020. (link).

J. Vázquez‐Lozano, A. Martínez, «Toward Chiral Sensing and Spectroscopy Enabled by All‐Dielectric Integrated Photonic Waveguides», Laser and Photonics Reviews,  14, 9, 2020. (link)

P.Roelli, D. Martin-Cano, T. J. Kippenberg, C.Galland, «Molecular Platform for Frequency Upconversion at the Single-Photon Level», Physical Review X, 10, 031057, 2020. (link).

D. Kos, G. Di Martino, A. Boehmke, B. de Nijs, B. Dénes, T. Földes, S. Sangtarash, E. Rosta, H. Sadeghi, J. Baumberg, «Optical probes of molecules as nano-mechanical switches», Nature Communications11 (1), 5905, 2020. (link).

A. Xomalis, R. Chikkaraddy, E. Oksenberg, I. Shlesinger, J. Huang, E. Garnett, F. Koenderink, J. Baumberg, «Controlling optically driven atomic migration using crystal-facet control in plasmonic nanocavities», ACS Nano 2020, 14, 8, 10562–10568, 2020. (link)

Y. Zhang, R. Esteban, R. Boto, M. Urbieta, X. Arrieta, «Addressing molecular optomechanical effects in nanocavity-enhanced Raman scattering beyond the single plasmonic mode», Nanoscale,  3, 2021. (link).

A. Xomalis, X. Zheng, A. Demetriadou, A. Martinez, R. Chikkaraddy, J. Baumberg, «Interfering plasmons in coupled nanoresonators to boost light locatization and SERS», Nano Letters,  21, 6, 2512–2518, 2021. (link).

L. Mercadé, A. Barreda, A. Martínez, «Dispersive optomechanics of supercavity modes in high-index disks», Opt. Lett. 45, 5238-5241 (2020) (link).

2019/07/20 Cadena SER

La UPV desarrolla una herramienta para facilitar la detección de explosivos o drogas:

Link to article


Project Coordinator

Prof. Alejandro Martínez

Nanophotonics Technology Center – Universitat Politècnica de València

Camino de Vera s/n, Acceso K, Edificio 8F, Planta 2

46022 Valencia, Spain

Contact us for more information!