Quick search Find article
Quick search
Find article

Photoelectric spectroscopy of InAs/GaAs quantum dot structures in a semiconductor/electrolyte system

I A Karpovich1, S B Levichev1, S V Morozov1, B N Zvonkov2, D O Filatov3, A P Gorshkov1 and A Yu Ermakov1

Show affiliations


The effects of bias voltage and cladding layer thickness on the surface photovoltage in the semiconductor/electrolyte system (PSE) of InAs/GaAs quantum dot (QD) structures grown by atmospheric-pressure metal organic vapour phase epitaxy have been investigated. It was shown that the effect of compensation of the normal component of the photovoltage by the lateral component in the structures with an asymmetric point ohmic contact may help to reveal details of the energy spectrum of the QDs. Using this effect, it was shown that emission of electrons and holes from the QDs to the barrier at strong electric field occurs directly from the excited levels, without relaxation to the ground state. The observed broadening of the optical transition lines in QDs in a strong electric field was related to the lifetime of the carriers in the excited levels in QDs, according to the uncertainty relation. The lifetime of the carriers in QDs was limited by the carrier emission rate from QDs to the matrix through a triangle barrier at strong electric field. The possibility of in situ investigation of the processes of formation and passivation of the surface traps resulting from electrochemical reactions in the electrolytic cell by PSE spectroscopy has been demonstrated.


PACS

68.65.Hb Quantum dots (patterned in quantum wells)

79.60.Bm Clean metal, semiconductor, and insulator surfaces

79.60.Jv Interfaces; heterostructures; nanostructures

72.40.+w Photoconduction and photovoltaic effects

Subjects

Condensed matter: electrical, magnetic and optical

Surfaces, interfaces and thin films

Nanoscale science and low-D systems

Dates

Issue 4 (August 2002)

Received 24 July 2001, in final form 7 November 2001

Published 28 May 2002



Related review articles

What's this?
View review articles related to this research to gain an insight into the key trends in this subject area. Related review articles are selected based on PACS/MSC codes, and are no more than three years old.

  1. Reactive diffusion in multilayer metal/silicon nanostructures
  2. GaAs nanowires and related prismatic heterostructures
  3. The structure of hybrid radial superlattices

View by subject




Export








Please login to access our web services, or create an account if you don't yet have one.

You must have cookies enabled in your web browser to be able to login.

Username
Password

Forgotten your password? Get a new one here.