Fine structure of spatial diode photoresponse profiles measured while scanning a narrow strip-shaped illumination spot with FPA diode

The three-dimensional Monte Carlo simulation of charge-carrier diffusion in a mercury-cadmium-tellurium based focal plane array (FPA) was used to calculate the spatial diode photoresponse profiles measured while scanning a narrow strip-shaped illumination spot with a selected FPA diode in the limit of largest and lowest diode photocurrents. The simulation was performed for a standard 2D n-on-p FPA with square photodiodes. Fine features in measured spot-scan profiles due to the presence of FPA structure were identified, and the de-pendence of these features on the boundary conditions for diffusing charge carriers at the n-type diode regions was demonstrated. An explanation to the shape of the profiles, fully con-sistent with the computational procedure of the problem, is given.

Download Full-text

Monte Carlo Simulation of Charge Carrier Diffusion for Determining the Spatial Resolution of Infrared Cadmium—Mercury—Tellurium Detectors

Optoelectronics Instrumentation and Data Processing ◽

10.3103/s8756699019050169 ◽

2019 ◽

Vol 55 (5) ◽

pp. 519-524

Author(s):

A. V. Vishnyakov ◽

V. V. Vasiliev ◽

I. V. Sabinina ◽

G. Yu. Sidorov ◽

V. A. Stuchinsky

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Charge Carrier ◽

Spatial Resolution ◽

Carrier Diffusion ◽

Charge Carrier Diffusion

Download Full-text

Charge Carriers Density, Temperature, and Electric Field Dependence of the Charge Carrier Mobility in Disordered Organic Semiconductors in Low Density Region

Condensed Matter ◽

10.3390/condmat6040038 ◽

2021 ◽

Vol 6 (4) ◽

pp. 38

Author(s):

Seyfan Kelil Shukri ◽

Lemi Demeyu Deja

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Charge Carrier ◽

Electric Field ◽

Organic Semiconductors ◽

Localization Length ◽

Charge Carriers ◽

Density Region ◽

Electric Field Dependence

We investigate the transport properties of charge carriers in disordered organic semiconductors using a model that relates a mobility with charge carriers (not with small polarons) hopping by thermal activation. Considering Miller and Abrahams expression for a hopping rate of a charge carrier between localized states of a Gaussian distributed energies, we employ Monte Carlo simulation methods, and calculate the average mobility of finite charge carriers focusing on a lower density region where the mobility was shown experimentally to be independent of the density. There are Monte Carlo simulation results for density dependence of mobility reported for hopping on regularly spaced states neglecting the role of spatial disorder, which does not fully mimic the hopping of charge carriers on randomly distributed states in disordered system as shown in recent publications. In this work we include the spatial disorder and distinguish the effects of electric field and density which are not separable in the experiment, and investigate the influence of density and electric field on mobility at different temperatures comparing with experimental results and that found in the absence of the spatial disorder. Moreover, we analyze the role of density and localization length on temperature and electric field dependence of mobility. Our results also give additional insight regarding the value of localization length that has been widely used as 0.1b where b is a lattice sites spacing.

Download Full-text