Stability of Excited Exciton States in Semiconductor Quantum Dots Under a Lateral Electric Field

The effect of the lateral electric field (LEF) on the excited and ground state stability of an exciton ([Formula: see text]) confined in a parabolic cylindrical quantum dot (QD) was estimated in this study. The calculation was performed in the framework of single-band effective mass theory using a variational approach. Our results revealed that the ground state binding energy of [Formula: see text] decreases with increasing the cylindrical QD radius until the exciton stability is lost at moderate LEF strength. By increasing the LEF strength, the excited heavy-hole ([Formula: see text]) can create an excited state [Formula: see text] or excited state [Formula: see text] of [Formula: see text], and the results indicate that the first state is more stable. In contrast, when an excited electron ([Formula: see text]) combines with an excited hole ([Formula: see text]) or unexcited hole ([Formula: see text]), it contains no split excited states for [Formula: see text] with less binding energy than the state [Formula: see text]. Comparing our previous results of donor impurity [Formula: see text] with [Formula: see text], we found that [Formula: see text] has a more stable ground state than [Formula: see text]. Moreover, the excited [Formula: see text] states are more stable than the excited states of [Formula: see text]. The quantum Stark shift (QSS) of the light- and heavy-hole exciton energy was explored, and a blue-shifted and quadratic QSS was observed. In contrast, for single particles (electron, heavy-hole and light hole), a red-shifted and linear QSS was observed.

Lateral electric field inhibits gel-to-fluid transition in lipid bilayers

We report evidence of lateral electric field-induced changes in the phase transition temperatures of lipid bilayers. Our atomic scale molecular dynamics simulations show that lateral electric field increases the melting temperature of DPPC, POPC and POPE bilayers. Remarkably, this shift in melting temperature is only induced by lateral electric field, and not normal electric field. This mechanism could provide new mechanistic insights into lipid-lipid and lipid-protein interactions in the presence of endogenous and exogenous electric fields.