Quantum Dynamics (QD)
The research interests of the QD group are quantum coherent dynamics and quantum many-body phenomena in designed nanosystems.
Physics Research Seminar: Alessio Recati (CNR-INO BEC Centre)
Research Director Alessio Recati from the CNR-INO BEC Centre in Trento gives a talk on sounds and vortices in supersolid dipolar gases.
When
–
Where
Room N228
Event language(s)
English
Welcome to a research seminar by Alessio Recati, Research Director at the CNR-INO BEC Centre in Trento!
Host: Dr. Sebastiano Peotta (Quantum Dynamics)
Title: Sounds and vortices in supersolid dipolar gases
Abstract:
A supersolid is a rather peculiar state of matter, which combines solid and superfluid features [1]. A subtle phase, which was proposed more than half-a-century ago for He-4 [2] and that has been recently observed in a few ultra-cold gases platforms [3-5]. In this talk we discuss the supersolid phase realised in Bose-Einstein condensed dipolar gases [6].
After describing how supersolidity arises in such a system and its experimental evidence, we shall focus on two features of such a state at zero temperature: 1) sound propagation and 2) quantised vortices.
1) Sound propagation, related to the presence of Goldstone modes, is shown to provide information on the superfluid and solid hydrodynamic parameters, to present an anomalous peculiar Doppler effect and an experimental protocol to measure them is proposed [7].
2) Quantised vortices, the hallmarks of superfluidity, are described in the supersolid state, and it is shown that they have a number of interesting features [8], different from their counterpart in
standard superfluid dilute gases. Very recently the first experimental observation of quantised vortices in a supersolid dipolar gas has also been obtained [9].
Dr. Alessio Recati is a physicist working at the Pitaevskii Center for Bose-Einstein Condensation in Trento, Italy. His research activity mainly focuses on the field of ultra-cold gases. In recent years, he has been working on dipolar gases, Bose-Bose mixtures, Fermi and Bose superfluidity, polaron physics, low-dimensional systems and analog models.
References:
[1] Balibar, S. The enigma of supersolidity. Nature 464, 176 (2010).
[2] Andreev, A. F. & Lifshitz, I. M. Quantum theory of defects in crystals. Sov. Phys. JETP 29, 1107 (1969).
[3] Léonard, J., Morales, A., Zupancic, P., Esslinger, T. & Donner, T. Supersolid formation in a quantum gas breaking a continuous translational symmetry. Nature 543, 87 (2017).
[4] Li, J.-R. et al. A stripe phase with supersolid properties in spin–orbit-coupled bose–einstein condensates. Nature 543, 91(2017).
[5] Tanzi, L. et al. Observation of a dipolar quantum gas with metastable supersolid properties. Phys. Rev. Lett. 122, 130405 (2019); Böttcher, F. et al. Transient supersolid properties in an array of dipolar quantum droplets. Phys. Rev. X 9, 011051 (2019); Chomaz, L. et al. Long-lived and transient supersolid behaviors in dipolar quantum gases. Phys. Rev. X 9, 021012 (2019).
[6] Recati, A. & Stringari, S. Supersolidity in ultracold dipolar gases. Nature Reviews Physics 5, 735 (2023).
[7] M. Šindik, T. Zawiślak, A. Recati, and S. Stringari, Sound, Superfluidity, and Layer Compressibility in a Ring Dipolar Supersolid, Phys. Rev. Lett. 132, 146001 (2024); T. Zawiślak, M. Šindik, S. Stringari, A. Recati, Anomalous Doppler effect in superfluid and supersolid atomic gases, arXiv:2408.16489.
[8] A. Gallemí, S. M. Roccuzzo, S. Stringari, and A. Recati, Quantized vortices in dipolar supersolid Bose-Einstein-condensed gases Phys. Rev. A 102, 023322 (2020); M. Šindik, A. Recati, S. Roccuzzo, L. Santos, and S. Stringari, Creation and robustness of quantized vortices in a dipolar supersolid when crossing the superfluid-to-supersolid transition, Phys. Rev. A 106, L061303 (2022).
[9] E. Casotti et al., Observation of vortices in a dipolar supersolid, Nature 635, 327 (2024)
