Colloidal quantum emitters
We study semiconductor quantum dots and perovskite nanocrystals as solid-state light sources with single-photon statistics.
Quantum Nanospectroscopy Materials Physics Center Donostia-San Sebastián
Controlling quantum light with colloidal nanocrystals and hybrid cavities
We study how plasmonic nanocavities and tunable optical microcavities can control the emission of individual colloidal quantum emitters. Our goal is to improve single-photon purity, brightness, emission rate and indistinguishability without redesigning the emitter material.
01 Research
Photonic control at the single-emitter level
The group investigates how the photonic environment around an individual emitter can control its quantum optical response. This approach aims to tune emission without changing the material structure of the emitter.
Plasmonic light-matter coupling
We couple the radiative transitions of individual emitters to plasmonic nanocavities to control emission at the nanoscale.
Tunable optical microcavities
We use optical microcavities as tunable photonic environments for controlling brightness, emission rate and photon indistinguishability.
Current research activity
From stable perovskite nanocrystals to cavity-coupled single-photon emitters
The group’s current work programme connects materials preparation, predictive modelling and quantum-optical measurements.
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Synthesis and functionalisation
Develop perovskite nanocrystals across different compositions and emission wavelengths, and study how surface ligands and polymer matrices influence optical stability.
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Hybrid emitter design
Combine electromagnetic and quantum modelling with the fabrication of plasmonic nanocavities and the integration of selected nanocrystal structures.
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Quantum optical characterisation
Measure individual emitters under ambient and cryogenic conditions using time-resolved spectroscopy, photon correlations and Hong-Ou-Mandel interferometry.
02 Experimental capabilities
From nanocrystal synthesis to photon-correlation measurements
The available facilities support nanocrystal preparation, ensemble optical spectroscopy and measurements on individual quantum emitters.
Materials preparation
Nanocrystal synthesis laboratory
Facilities for the synthesis of colloidal quantum dots.
Technical details
A chemical laboratory equipped for quantum dot synthesis.
Absorption spectroscopy
Cary UV-Vis
Agilent
Technical details
UV-Vis spectrophotometer for ensemble optical measurements.
Optical spectroscopy
Cary Eclipse
Agilent
Technical details
Spectrophotometer for ensemble optical measurements.
Time-resolved microscopy
MicroTime 200
PicoQuant
Technical details
Single-particle time-resolved fluorescence and photon-correlation measurements in a Hanbury Brown and Twiss configuration with two avalanche photodetectors.
Single-particle spectroscopy
Kymera 193i
Andor
Technical details
Ultrasensitive spectrograph connected to the fluorescence microscope for spectral measurements at the single-particle level.
Femtosecond excitation
Chameleon Ultra
Coherent
Technical details
Ti:sapphire laser with pulses down to 50 fs across 680 to 1080 nm. Second-harmonic generation extends the available wavelength range to 340 to 540 nm.
Photon indistinguishability
Hong-Ou-Mandel setup
Custom-built
Technical details
Two high-speed single-photon photodetectors enable photon indistinguishability measurements.
03 People
Our team
Quantum Nanospectroscopy is part of the Nanomaterials and Spectroscopy Group. The parent group is led by Prof. Dr. Yury P. Rakovich, and its researchers work across colloidal nanomaterials, nanophotonics, spectroscopy and light-matter coupling.
Dr. Victor Krivenkov
Quantum Nanospectroscopy lead
Materials Physics Center
Victor Krivenkov has more than 10 years of experience developing colloidal fluorescent nanocrystals and plasmonic nanostructures. His research focuses on light-matter-coupled quantum emitters that integrate semiconductor nanocrystals with nano- and microcavities.
Prof. Dr. Yury P. Rakovich
Head, Nanomaterials and Spectroscopy Group
Ikerbasque Research Professor Materials Physics Center
Yury P. Rakovich heads the Nanomaterials and Spectroscopy Group at the Materials Physics Center. His research covers nanophotonics, the optics of organic and inorganic hybrid nanostructures and strong light-matter interaction. He is a senior member of the Optical Society of America.
Dr. Alexey Nikitin
Ikerbasque Research Professor
Donostia International Physics Center
Alexey Nikitin develops theory for optical phenomena in natural van der Waals materials, artificial low-dimensional materials and metamaterials. His research includes hyperbolic light and near-field microscopy. His previous research experience includes the University of Zaragoza and CIC nanoGUNE.
Dr. Adam Olejniczak
Alumnus
Materials Physics Center
During his time with the group, Adam Olejniczak studied light-matter interactions in colloidal quantum emitters, strongly coupled plexcitonic systems and J-aggregates in photonic microcavities. He used time-correlated single-photon counting to investigate optical processes at the single-particle level. He was awarded a Juan de la Cierva fellowship.
Mr. Jehyeok Ryu
PhD student
Donostia International Physics Center
Jehyeok Ryu is a DIPC PhD student working within the Nanomaterials and Spectroscopy research line. His recent work with the group addresses the synthesis, photostability and single-photon emission of perovskite quantum dots.
04 Research output
Selected publications
Recent work from the group. Titles link to the publisher, DOI record or arXiv preprint.
2026
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PreprintarXiv:2602.11385
When Blinking Helps: Suppressed Biexciton Emission in Lead Halide Perovskite Quantum Dots
arXiv preprint, arXiv:2602.11385
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PreprintarXiv:2601.15898
Size-dependent Dielectric Permittivity of Perovskite Nanocrystals
arXiv preprint, arXiv:2601.15898
2025
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ArticleAdvanced Functional Materials
Facile Van der Waals hBN Encapsulation and Stabilization of Perovskite Quantum Dots Emission
Advanced Functional Materials. DOI: 10.1002/adfm.202527591
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ArticleNano Letters
Nickel Doping Unlocks Ambient-Condition Photostability in Individual Cesium Lead Bromide Perovskite Quantum Dots
Nano Letters, 25(47), 16630-16636. DOI: 10.1021/acs.nanolett.5c04099
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ArticleApplied Physics Reviews
Perovskite Nanocrystals as Emerging Single-Photon Emitters: Progress, Challenges, and Opportunities
Applied Physics Reviews, 12(4), 041323. DOI: 10.1063/5.0282667
2024
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ArticleAPL Photonics
On-demand Reversible Switching of the Emission Mode of Individual Semiconductor Quantum Emitters Using Plasmonic Metasurfaces
APL Photonics, 9(1), 016107. DOI: 10.1063/5.0170535
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ArticleMaterials for Quantum Technology
Advancements and Challenges in Plasmon-Exciton Quantum Emitters Based on Colloidal Quantum Dots and Perovskite Nanocrystals
Materials for Quantum Technology, 4(3), 032001. DOI: 10.1088/2633-4356/ad6b6d
05 Contact
Contact the group
For research questions, potential collaborations or information about the group, contact Victor Krivenkov or Yury Rakovich.
Telephone
Address
Materials Physics Center
Paseo de Manuel Lardizabal, 5
20018 Donostia-San Sebastián, Gipuzkoa, Spain