H2020Индивидуална стипендия2019–2021

UltraLiquid · Dynamics and Thermodynamics of Ultradilute Liquids

„Хоризонт 2020“ — Действия „Мария Склодовска-Кюри“

Период: 2019-09-01 → 2021-08-31
Финансиране от ЕС: 158 122 €
Участници: 1
Схема: MSCA-IF-EF-ST

Линиите свързват координатора с партньорите.

Накратко на български

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Този кратък обзор е генериран от изкуствен интелект

Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.

Резултати накратко

Dynamics and Thermodynamics of Ultradilute Liquids

One of the most exciting recent discoveries in ultracold mixtures of two bosonic atomic ensembles is the experimental realization in 2018 of novel liquids featuring densities and temperatures which are eight to ten orders of magnitude smaller than water. Nonetheless, the thermodynamics of such quantum liquids remains unexplored due to large three-atom losses, which hinder their experimental study. In one spatial dimension, losses are limited thus providing enhanced stability to the system. That greater stability is achieved even in a single-component system, where the understanding of thermodynamic properties is still an open issue in our field. The solution to such a central problem is of paramount importance to shed light also on the properties of ultradilute liquids. A system of bosons moving along one dimension looks deceivingly simple, but it is actually an extremely sophisticated system due to the intricate interplay of thermal motion, collisions, and quantum statistics. Importantly, this problem is not a merely academic one since these systems have been experimentally realized since 2004 with ultracold gases. A problem that remained open until now was the understanding of the microscopic mechanisms ruling the thermodynamic behavior of these extremely quantum systems. In addition, thermodynamic quantities already showed an anomaly in their temperature dependence, resembling the presence of a phase transition. However, a peculiarity of one-dimensional geometry is that phase transitions cannot occur, making the issue extremely puzzling. Finally, the complete in-depth understanding of microscopic correlation properties was still missing. In this project, we have investigated the thermal properties of ultracold bosonic gases and liquids in a one-spatial dimension. Besides the solution of the challenging problems listed above, we have discovered radically new quantum regimes and phenomena and proposed how they can be explored in cutting-edge experiments. Ultracold gases and liquids allow for far-reaching investigations of quantum many-body effects and high-resolution measurements inconceivable so far. These promise innovative applications in quantum metrology and sensing. Finally, the understanding of thermal properties, enhanced by the quantum simulation of very different systems ensured by ultracold ensembles, is relevant for the development of future quantum technologies, innovative materials, high-critical-temperature superconductors, and quantum computers.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз

Цел на проекта

Quantum mixtures dominate the physics of helium liquids, neutron stars, nuclear matter, quark-gluon plasma, quantum magnets and superconductors, but these systems are so dense that their completeunderstanding remains a distant goal. Ultracold quantum mixtures of two bosonic gases constitute an ideally-tunable platform which allows for a complete control over interactions, temperature, and dimensionality, an in-depth understanding of the physics at stake, and the exploration of radically new phenomena. In state-of-the-art experiments on these mixtures, small clusters of atoms (1000-10000) were shown to become self-bound and highly-incompressible, due to the balance of attractive and repulsive forces. First observed in 2017, these liquid droplets constitute a new state of matter, much denser than quantum gases, but orders of magnitude more dilute and colder than any other liquid in Nature. A key property of these systems is that mean-field interactions are tuned to be overall weakly-attractive, sothat the stabilization mechanism which leads to droplet formation is provided only by quantum fluctuations. In mixtures where atoms of one component largely outnumber the others, the minority atoms become dressed by majority collective excitations forming Bose polarons, first observed in 2016. When polarons are immersed in a weakly-interacting bath, a controlled theoretical approach is possible evenwhen polaron-bath interactions are strong. Droplets and polarons constitute, respectively, the balanced and the highly-imbalanced limits of quantum mixtures, and the ""UltraLiquid"" project will lay theoretical firm ground for the unified description of their dynamics and thermodynamics, which will direct future experiments, and in close collaboration with ourteam. These systems allow for far-reaching investigations of quantum many-body effects and high-resolution measurements inconceivable so far. These promise innovative applications in quantum metrology and quantum sensing.""

Оригинален текст от CORDIS (на английски).

Участници

UNIVERSITAT POLITECNICA DE CATALUNYA · BARCELONAКоординаторИспания