
%0 Journal Article
%A Hamilton, A. R. 
%A Simmons, M. Y. 
%A Pepper, M. 
%A Ritchie, D. A. 
%T Influence of Inversion Symmetry on the Metallic Behaviour in a Dilute Two-dimensional Hole System
%J Australian Journal of Physics
%D 2001/02/23
%V 53
%N 4
%P 523-530
%K 
%R https://doi.org/10.1071/PH00019
%U https://www.publish.csiro.au/paper/PH00019 
%X In the past five years numerous experimental studies of a wide variety of low disorder two-dimensional (2D) semiconductor systems have revealed an unexpectedly large decrease in the resistance as the temperature is lowered from T &#126; 1 K, suggesting the existence of a 2D metal. Although numerous theories have been put forward to explain this metallic-like behaviour (which contradicts the expectations of one parameter scaling theory), its origins, and the question of whether it persists to T = 0, are still subjects of great debate. We present a detailed study of the influence of inversion symmetry on the B = 0 metallic behaviour in a low density GaAs hole gas close to the apparent two-dimensional metal&#8212;insulator transition. The strength of the metallic behaviour (determined by the size of the drop in resistance as T&rarr; 0) is found to be almost independent of the electric field across the hole gas, and is predominantly determined by the magnitude of k F l at low temperatures (i.e. by the low temperature resistivity). These results suggest that the shape of the potential well and spin&#8212;orbit effects alone cannot account for the existence of metallic behaviour in low density, strongly interacting 2D systems. 
