Dislocation-position fluctuations in solid He-4 as collective variables in a quantum crystal

Autor(es)

de Koning, Maurice ; Cai, Wei

• Tipo de documento: Artigo Científico
• Fonte: NPJ QUANTUM MATERIALS; v. 7, n. 1, p. 7-pg., 2022-12-27.

Resumo

Quantum behavior at mesoscopic length scales is of significant interest, both from a fundamental-physics standpoint, as well as in the context of technological advances. In this light, the description of collective variables comprising large numbers of atoms, but nevertheless displaying non-classical behavior, is a fundamental problem. Here, we show that an effective-Hamiltonian approach for such variables, as has been applied to describe the quantum behavior of coupled qubit/oscillator systems, can also be very useful in understanding intrinsic behavior of quantum materials. We consider lattice dislocations - naturally occurring mesoscopic line defects in crystals - in the prototypical bosonic quantum crystal, solid He-4. For this purpose, we map fully atomistic quantum simulations onto effective one-dimensional Hamiltonians in which the collective dislocation-position variables are represented as interacting, massive quantum particles. The results provide quantitative understanding of several experimental observations in solid He-4. (AU)

• Processo FAPESP: 13/08293-7 - CECC - Centro de Engenharia e Ciências Computacionais
• Beneficiário: Munir Salomao Skaf
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 16/23891-6 - Modelagem computacional da matéria condensada
• Beneficiário: Alex Antonelli
• Modalidade de apoio: Auxílio à Pesquisa - Temático