Physical Limit of Nonlinear Brownian Oscillators in Quantum Trap.
J Phys Chem Lett
; 15(6): 1719-1725, 2024 Feb 15.
Article
em En
| MEDLINE
| ID: mdl-38320267
ABSTRACT
Quantum trap, a quantum and thermal fluctuations-induced nonmonotonous potential, offers a chance to build up microscopic mechanical systems completely dominated by fluctuations. Here, we explore the physical limit of the effective damping ratio of the nonlinear Brownian oscillator in a quantum trap, set by the finite separation for avoiding molecular-scale effects on the trap potential and the surface confinement effect-induced diverging damping and random forces. The quasiharmonic approximations and Langevin dynamics simulations show that the lowest effective damping ratios of the suspended Au plate and Au sphere upon a Teflon coating of 10 nm can be â¼210 and â¼145, respectively, at room temperature. Perforation is proposed as an effective route to reduce the damping ratio (down to 6.4) by attenuating the surface confinement effect. An unexpected result due to the temperature dependences of dielectric function and viscosity of ethanol is a further reduced damping ratio at 400 K (1.3). The nonlinear Brownian oscillator in the quantum trap shows promise of probing near-boundary hydrodynamics at nanoscale.
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01-internacional
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MEDLINE
Idioma:
En
Revista:
J Phys Chem Lett
Ano de publicação:
2024
Tipo de documento:
Article