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1.
Phys Rev Lett ; 130(2): 026201, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36706406

RESUMO

The concept of quantum phase transitions (QPTs) plays a central role in the description of condensed matter systems. In this Letter, we perform high-quality wave-function-based simulations to demonstrate the existence of a quantum phase transition in a crucially relevant molecular system, namely, water, forming linear chains of rotating molecules. We determine various critical exponents and reveal the water chain QPT to belong to the (1+1)-dimensional Ising universality class. Furthermore, the effect of breaking symmetries is examined, and it is shown that, by breaking the inversion symmetry, the ground state degeneracy of the ordered quantum phase is lifted to yield two many-body states with opposite polarization. The possibility of forming ferroelectric phases together with a thermal stability of the quantum critical regime up to ∼10 K makes the linear water chain a promising candidate as a platform for quantum devices.

2.
J Chem Phys ; 150(18): 184105, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091890

RESUMO

In this contribution, we present a quantum dynamical approach to study inelastic scattering of diatomic molecules from metal surfaces at normal incidence. The dissipative dynamics obeys a stochastic Schrödinger equation describing the time-evolution of the system as a piecewise deterministic process. Energy exchange between the molecular vibrational degrees of freedom and the metal electrons is represented using operators in tensor product form, which are coupled via anharmonic transition rates calculated from first-order perturbation theory. Full dimensional observables are obtained by averaging over simulations in 4D-including the internal stretch, the distance to the surface, and the orientation angles-at different surface sites. The method is applied to the state-resolved scattering of vibrationally excited NO from Au(111), revealing important channels for quantized energy relaxation.

3.
Am Ann Deaf ; 145(3): 256-62, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10965588

RESUMO

The study examined the views of deaf and hard of hearing secondary-level students when asked about their preferences for deaf vs. hearing teachers. It also compared elementary- and secondary-level students' achievement scores based on the hearing status of their teachers. Deaf and hard of hearing secondary-level students showed greater preference for deaf teachers, with deaf students showing greater preference for deaf teachers than hard of hearing students did. No significant differences were found in the achievement levels of students based on differences in teacher hearing status. The study supports the limited research done in the past.


Assuntos
Surdez , Audição , Percepção , Ensino , Logro , Adolescente , Adulto , Feminino , Humanos , Masculino
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