Novel optical probe for quantum Hall system

BISWAJIT KARMAKAR and BRIJ MOHAN ARORA

Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba,

Mumbai 400 005, India

E-mail: brij@tifr.res.in; brijmohanarora@yahoo.com

Abstract. Surface photovoltage (SPV) spectroscopy has been used for

the first time to explore Landau levels of a two-dimensional electron

gas (2DEG) in modulation doped InP/InGaAs/InP QW in the quantum Hall

regime. The technique gives spectroscopically distinct signals from

the bulk Landau levels and the edge states. Evolution of the bulk

Landau levels and the edge electronic states is investigated at 2.0 K

for magnetic field up to 8 T using SPV spectroscopy.

Keywords. Surface photovoltage spectroscopy; quantum Hall effect;

Landau levels; edge states.

PACS Nos 73.43.-f; 07.60.-j; 73.43.Fj