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Ultrafast Dynamics of Quantum Materials

We are a new research group at Aarhus University that exploits ultra-short pulses of laser light from across the entire electromagnetic spectrum to explore and control the properties of materials. Our focus is on understanding the properties of "quantum materials", materials that show interesting and unexpected phenomena at unusually high temperatures, such as high temperature superconductivity. By using photons that range in energy from 5 meV to 15 keV we can study atomic, spin and electron dynamics on nanometer lengthscales and femtosecond timescales. Our work exploits laboratory sources of laser light, as well as the use of X-ray lasers around the world. 

New Publication

Our latest work entitled "Does VO2 host a transient monoclinic metallic phase?" is published in Physical Review X. 

This work is an experimental tour-de-force, led by former ICFOian PhD student Luciana Vidas, covers dynamics of the light-induced insulator-metal phase transition in VO2. Measurements captured the dynamics of the phase transition from femto- to mili-seconds and spectroscopy of the transient state was performed from the mid-IR to the soft X-ray region.  

Our work showed that, contrary to previous claims, the structural and electronic aspects of the phase transition remain "locked" together and it is not possible to generate a metallic monoclinic phase. We also show that the thermal energy in the lattice is key for understanding the ultrafast phase transition in VO2.


New Pre-Print

Our latest work on soft X-ray imaging and nanoscale spectroscopy of the insulator-metal phase transition in VO2 is now available on the arXiv. One of the few good things about the COVID crisis, Allan went through our old holography data and was able to implement a partial coherence algorithm to provide access to the complex refractive index, enabling us to obtain the exact spectra of our sample. 


New Group Member

Maurizio Monti becomes the first member of the Aarhus team after completing his PhD at the University of Warwick. Welcome Maurizio


CMD2020 Talk Online

Watch Allan Johnson's talk on hyper-spectral coherent diffractive imaging of the phase transition in VO2 for the CMD2020 virtual conference online now!


Poster Preview for CMD2020

For a summary our latest work on the ultrafast dynamics of orbital order in the manganites, take a look at the poster prepared by Daniel Perez. Dani has been developing an innovative method to obtain the dynamics of the optical anisotropy in response to photoexcitation, which he has used to directly probe the ultrafast melting of orbital order. The poster will be presented at the biennial meeting of the Condensed Matter Divisions of the European and Spanish physics societies (CMD2020GEFES)


Moving to Aarhus University

Despite the corona virus, we are moving from Barcelona to Aarhus university! Simon is already full time at Aarhus, and the first lab should arrive in the beginning of October. Stay tuned for more information!