Search
Now showing items 1-4 of 4
Ab initio calculation of low-energy collective charge-density excitations in MgB2
(American Physical Society, 2009-08)
We present ab initio time-dependent density-functional theory calculation results for low-energy collective electron excitations in MgB2. The existence of a long-lived collective excitation corresponding to coherent charge ...
Upconversion cooling of Er-doped low-phonon fluorescent solids
(American Physical Society, 2009-01)
We report on a novel mechanism for laser cooling of fluorescent solids based on infrared-to-visible upconversion often found in rare-earth-doped low-phonon materials. This type of optical cooling presents some advantages ...
Position-dependent exact-exchange energy for slabs and semi-infinite jellium
(American Physical Society, 2009-12)
The position-dependent exact-exchange energy per particle epsilon(x)(z) (defined as the interaction between a given electron at z and its exact-exchange hole) at metal surfaces is investigated, by using either jellium slabs ...
Exchange-Correlation Hole of a Generalized Gradient Approximation for Solids and Surfaces
(American Physical Society, 2009-02)
We propose a generalized gradient approximation (GGA) for the angle- and system-averaged exchange-correlation hole of a many-electron system. This hole, which satisfies known exact constraints, recovers the Perdew-Burke-Ernzerhof ...