Welcome to Tomasz Smoleński's webpage


I am an experimental physicist with over 14 years of research experience at the intersection of condensed matter physics, quantum materials and quantum optics. In my research, I design custom low-dimensional electrically-tunable semiconductor structures and use to them to explore fundamental emergent quantum phenomena in low-temperature magneto-optical experiments. 

I work as a Senior Postdoctoral Researcher in the Quantum Photonics Group of Prof. Atac Imamoglu at ETH Zurich. My current research activity is mainly focused on developing novel optical quantum sensing techniques for detecting and visualizing strongly correlated electronic phases, such as electronic Wigner crystals, fractional quantum Hall liquids or unusual Nagaoka electronic magnets. I explore these emergent phases of matter by means of optical spectroscopy of quantum materials based on van der Waals heterostructures. 

I obtained my PhD in 2018 at the Faculty of Physics, University of Warsaw on optimizing the properties of ultimate magnetic memories based on the spin of an individual magnetic dopant embedded inside a semiconductor quantum dot. My experiments were carried out in the Laboratory of Ultrafast Magneto-Spectroscopy LUMS.

Feel free to learn more about my research interests and scientific papers. You may also want to check my citations at Google Scholar or visit my LinkedIn profile.

Contact: tomaszs_at_phys.ethz.ch

Research Highlights

Direct optical signature of the electronic

 Wigner crystal

If the strength of interactions between the electrons in 2D semiconductor exceeds their kinetic energy, the electrons form a spatially-ordered, Wigner crystal state. Here we provide a direct evidence for the emergence of this elusive state of matter using a novel optical technique that relies on the observation of exciton umklapp scattering in the periodic potential generated by the electrons forming the crystal.

T. Smoleński et al.,  Nature 595, 53-57 (2021)

Evidence for unusual electronic magnetism in an extended 2D system

In typical metals or ferromagnets, collective electronic magnetism arises due to the exchange interaction, which allows the electrons to lower their Coulomb repulsion by aligning their spins. Here we provide a direct experimental evidence for a different, Nagaoka ferromagnetism that occurs due to minimization of kinetic energy of itinerant electrons.

L. Ciorciaro*, T. Smoleński* et al.,
Nature 623, 509-513 (2023)

Optical sensing of fractional quantum Hall effect in optically-inaccessible materials

Despite its great electronic properties, graphene is very hard to access by optical means. Here we utillize Rydberg excitons in a proximal transition metal dichalcogenide monolayer to optically sense the formation of fractional quantum Hall effect in graphene with a sensitivity comparable to state-of-the-art transport methods.

A. Popert, (...), and T. Smoleński .,  Nano Letters 22, 7363-7369 (2022)

Fully-tunable electrostatic confinement of excitons in one and zero dimensions

Although spatial motion of excitons can be confined in self-assembled quantum dots or strain-induced defects, such an approach does not provide in-situ tunability. Here we realize all-electrostatic, fully-tunable confinement of excitons in 1D and 0D by creating later p-i-n junctions in monolayer of transition metal dichalcogenide.

D. Thureja*, E. Yazici*, T. Smoleński* et al.,
arXiv:2402.19278 (2024)

D. Thureja, A. Imamoglu, T. Smoleński et al.,
Nature 606, 238-304 (2022)

Magnetic ground state of an individual Fe2+ ion in strained semiconductor nanostructure

The iron Fe2+ atom embedded in a semiconductor exhibits a single non-degenerate ground state of zero magnetic moment. Here we show that by using sufficiently large strain it is possible to tailor the energy spectrum of the iron atom to obtain doubly degenerate (magnetic) ground state, which can be utilized for storage and processing of the quantum information.

T. Smoleński et al.,  Nat. Commun. 7, 10484 (2016)