Collective quantum transport and light-assisted superconductivity

当代凝聚态物理是现代电子学和技术的基础。当与光学结合时，它代表了现代超快设备的强大平台。与此同时，位于这两个领域边界的多种现象，其中固态系统与光强烈耦合，仍有待探索，并可能包含尚未发现的基本效应。特别是，强烈的光-物质耦合的机制出现在纳米结构中，其中光学谐振器内放置了明显的激子共振，其中出现了混合光-物质准粒子，称为腔极化激元。极化激元学是一个迅速发展的领域，然而，极化激元物理学中的一个方面，即准粒子的量子统计性质和由此产生的量子关联，至今主要被忽视。虽然极化激元的物质部分由服从费米统计的电子和空穴组成的激子表示，但光部分由服从玻色统计的腔光子形成。此外，在器件中添加额外的层，可以使纯费米物质-电子-发挥作用。在玻色-费米混合物物理学的背景下，新型二维材料-具有过渡金属二硫属化物和石墨烯的原子薄层的突出例子-结合了联合收割机许多期望的特性，从强光学响应到相对简单和低制备成本，并允许创建由一个或多个隔离层组成的结构，所述隔离层容纳具有不同统计特性的粒子。这两种概念上不同的统计之间的相互作用为极化激元学领域带来了新的转折，并为观察其他类型系统中无法实现的新颖量子集体相位提供了机会。在这个项目中，我们将探讨如何大的光学非线性和强量子相关性，源于混合量子统计的影响，出现在强光-物质耦合的制度。建议的研究包括超流性，相关性，拖曳效应和超导电性，在这样的多层系统的电子和极化激元在微腔，与发展的具体设计的几何有利于观察创纪录的高光学非线性，集体量子输运，和光辅助超导行为。为了实现这个雄心勃勃的目标，密切纠缠的理论和实验项目，我们在极化激元学和二维材料领域汇集了一个强大的德国-俄罗斯学术联盟。该国际团队联合了世界领先的理论家，他们将建立层状几何结构中固态玻色-费米混合物的微观理论，以及开发新结构和观察拟议现象所需的无与伦比的实验设施。

Contemporary condensed matter physics is a foundation of the present-day electronics and technology. When merged with optics, it represents a powerful platform for modern ultrafast devices. At the same time, multiple phenomena lying at the border of these two realms, where solid-state systems are strongly coupled to light, are still to be explored, and potentially contain fundamental effects yet to be discovered. In particular, the regime of the strong light-matter coupling appears in nanostructures with pronounced excitonic resonance placed inside an optical resonator, where hybrid light-matter quasiparticles, known as cavity polaritons, emerge. Polaritonics is a rapidly developing field, however, one aspect in polariton physics, namely, corresponding quantum statistical properties of quasiparticles and resulting quantum correlations, was mainly overlooked up to now. While the matter part of a polariton is represented by an exciton, made from an electron and a hole that obey Fermi statistics, the light part is formed by a cavity photon obeying Bose statistics. Furthermore, adding extra layers to the device, one can bring purely fermionic species – electrons – into play.In the context of the physics of Bose-Fermi mixtures, novel two-dimensional materials – with prominent examples of atomically-thin layers of transition metal dichalcogenides and graphene – combine many desirable properties, from strong optical response to relative simplicity and low cost of preparation, and allow to create the structures consisting of one or several isolated layers hosting particles with different statistics. The interplay between the two conceptually different statistics brings a new twist into the domain of polaritonics, and presents an opportunity for observation of novel quantum collective phases unattainable in other kind of systems. In this project, we will explore how large optical nonlinearities and strong quantum correlations, stemming from the effects of the hybrid quantum statistics, appear in the regime of the strong light-matter coupling. Proposed studies include superfluidity, correlations, drag effects and superconductivity in such multi-layer systems of electrons and polaritons in a microcavity, with the development of specific designs of geometries favorable for the observation of record-high optical nonlinearities, collective quantum transport, and light-assisted superconducting behavior.To achieve the ambitious goals of this project that closely entwines theory and experiment, we bring together a strong German-Russian academic consortium in the field of polaritonics and two-dimensional materials. The international team unites world-leading theoreticians who will build the microscopic theory of solid-state Bose-Fermi mixtures in layered geometries, and unmatched experimental facilities necessary to develop the novel structures and observe the proposed phenomena.