Zero-point Pressure Research Articles

Mesoscopic capacitor and zero-point energy: Poisson's distribution for virtual charges, pressure, and decoherence control

Mesoscopic capacitor theory, which includes intrinsic inductive effects from quantum tunneling, is applied to conducting spherical shells. The zero-point pressure and the number of virtual charged pairs are determined assuming a Poisson distribution. They are completely defined by a dimensionless mesoscopic parameter (χc) measuring the average number of virtual pairs per solid angle and carrying mesoscopic information. Fluctuations remain finite and well defined. Connections with usual quantum-field-theory limit enables us to evaluate χc ~ 1.007110. Equivalently, for a mesoscopic parallel-plate capacitor, the shot noise distribution becomes operative with χc ~ 0.94705 as well being related to the density of virtual pairs. Temperature decoherence and capacitor control are discussed by considering typical values of quantum dot devices and Coulomb blockade theory.

Rossby waves in rapidly rotating Bose–Einstein condensates

We predict and describe a new collective mode in rotating Bose–Einstein condensates, which is very similar to Rossby waves in geophysics. In the regime of fast rotation, the Coriolis force dominates the dynamics and acts as a restoring force for acoustic-drift waves along the condensate. We derive a nonlinear equation that includes the effects of both zero-point pressure and inhomogeneity of the gas. It is shown that such waves have negative phase speed, propagating in the opposite sense of the rotation. We discuss different equilibrium configurations and compare them to those resulting from the Thomas–Fermi approximation.

Pressure induced insulator-metal transition of solid LiH

The equation of state and the electronic band structure of solid LiH have been calculated using the local-density functional theory with Ceperley and Alder's exchange-correlation potential in the muffin-tin approximation. The band gap is the direct gap with the X 1 minus; X′ 4 symmetries up to the band closing at V M =3.35 cm 3 mole −1. At further compression, the band crossing occurs between the state with the Z 1 symmetry and that of the Z 3 symmetry. The transition pressure of metallization is estimated to be P M =226 GPa. Using the Debye model, the zero-point pressure is also calculated with the Debye temperature theoretically determined. The Debye temperature of 7LiH at normal density is 1115 K in agreement with the experimental value 1190 ± 80 K.