Skip to main content

Hidden, entangled and resonating orders

Objective

Knowledge of the electronic band structure and a key low energy degree of freedom, chosen from a short list including charge, spin, free electrons and atomic positions, characterizes most crystalline solids with astonishing success. This paradigm underpins not only metallic and insulating behavior, but also superconductivity, the fractional quantum Hall effect and Mott physics where the efficient theoretical approach is always to consider many-body physics only for a single low energy degree of freedom. While much research even over the last 20 years has validated this paradigm, e.g. for graphene, there are examples of quantum matter where it seems to break down, most notably transition metal oxides which host what appear to be many “key” low energy degrees of freedom (order parameters) and even the quasiparticles in the “normal” metallic states do not always behave as ordinary electrons in metals. Our contention is that the truly important degrees of freedom are not awaiting discovery, but rather that the key property of many of these systems is that there are several key degrees of freedom. HERO aims to go beyond the state of the art in accounting for systems with multiple order parameters by considering all of the possibilities offered by quantum mechanics, and taking advantage of exceptional experimental and computational tools such as free electron lasers. We will search systematically for different forms of “Hidden” Order , derived either from correlations between classical order parameters which could even be vanishing due to quantum fluctuations or from external ac drive fields. Quantum multicritical points where different forms of order simultaneously appear near zero temperature will be considered with special attention to the effects of Entanglement between mesoscopic quantum variables associated with the multiple orders. Finally, we will examine the consequences of Resonant level crossings for symmetry-restoring modes associated with different orders.

Field of science

  • /natural sciences/physical sciences/quantum physics

Call for proposal

ERC-2018-SyG
See other projects for this call

Funding Scheme

ERC-SyG - Synergy grant

Host institution

PAUL SCHERRER INSTITUT
Address
Forschungstrasse 111
5232 Villigen Psi
Switzerland
Activity type
Research Organisations
EU contribution
€ 4 500 105

Beneficiaries (4)

PAUL SCHERRER INSTITUT
Switzerland
EU contribution
€ 4 500 105
Address
Forschungstrasse 111
5232 Villigen Psi
Activity type
Research Organisations
EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH
Switzerland
EU contribution
€ 2 499 999
Address
Raemistrasse 101
8092 Zuerich
Activity type
Higher or Secondary Education Establishments
ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE
Switzerland
EU contribution
€ 4 437 450
Address
Batiment Ce 3316 Station 1
1015 Lausanne
Activity type
Higher or Secondary Education Establishments
STOCKHOLMS UNIVERSITET
Sweden
EU contribution
€ 2 499 943,75
Address
Universitetsvagen 10
10691 Stockholm
Activity type
Higher or Secondary Education Establishments