Driver mandatory lane change behavior: Use of governing gap in critical gap estimation

This study analyzed the driver gap acceptance and rejection behavior during mandatory lane changes on a multilane freeway in congested and uncongested traffic conditions. During a lane change, drivers were more receptive to either the leading or the trailing gaps with vehicles in the target lane which governed the drivers\u27 lane change and is termed as the governing gap. Drivers maneuvered till the governing gap was greater than the critical gap, accepted the gap and made a lane change. In this process, drivers reduced the non-governing gap to increase the length of the governing gap. The drivers as a result were found to be consistent with respect to the governing gap and inconsistent with respect to the non-governing gap. The governing gap, therefore, addresses the consistent driver behavior and avoids categorization of drivers as inconsistent. Critical gaps were estimated based on the consistent driver behavior using accepted and LRLA gaps, firstly, by categorizing the drivers based on the governing gap and the type of maneuver, and secondly, by categorizing the drivers based on the relative speeds. For a simple lane change model, categorization by governing gap and type of maneuver will be sufficient with a critical gap value distribution defined by empirical data for congested and uncongested traffic conditions. For a sophisticated lane change model, in addition to maneuver types, critical gaps estimated based on difference in relative speeds will help better replicate the realistic lane change behavior of drivers in case of congested traffic conditions --Abstract, page iv

Probing dynamical symmetry breaking using quantum-entangled photons

We present an input/output analysis of photon-correlation experiments whereby a quantum mechanically entangled bi-photon state interacts with a material sample placed in one arm of a Hong-Ou-Mandel (HOM) apparatus. We show that the output signal contains detailed information about subsequent entanglement with the microscopic quantum states in the sample. In particular, we apply the method to an ensemble of emitters interacting with a common photon mode within the open-system Dicke Model. Our results indicate considerable dynamical information concerning spontaneous symmetry breaking can be revealed with such an experimental system

Research Update: Luminescence in lead halide perovskites

Efficiency and dynamics of radiative recombination of carriers are crucial figures of merit for optoelectronic materials. Following the recent success of lead halide perovskites in efficient photovoltaic and light emitting technologies, here we review some of the noted literature on the luminescence of this emerging class of materials. After outlining the theoretical formalism that is currently used to explain the carrier recombination dynamics, we review a few significant works which use photoluminescence as a tool to understand and optimize the operation of perovskite based optoelectronic devices

A dual-phase architecture for efficient amplified spontaneous emission in lead iodide perovskites

We report a way to overcome Auger recombination in lead iodide perovskites by investigating the domain structure forming below the phase transition temperature

Plasmonics in heavily-doped semiconductor nanocrystals

Heavily-doped semiconductor nanocrystals characterized by a tunable plasmonic band have been gaining increasing attention recently. Herein, we introduce this type of materials focusing on their structural and photo physical properties. Beside their continuous-wave plasmonic response, depicted both theoretically and experimentally, we also review recent results on their transient, ultrafast response. This was successfully interpreted by adapting models of the ultrafast response of gold nanoparticles.Comment: 20 pages review paper, 15 figure