1999/01/19 by Yael Hanein, Y. Hanein, D. Shahar +11 · 1 citation
Materials Science · Physics and Astronomy · #Electronic and Structural Properties of Oxides #Quantum and electron transport phenomena #Semiconductor Quantum Structures and Devices #cond-mat
paper · pdf · doi:10.48550/arxiv.cond-mat/9901186
4 figures
arxiv created 1999/01/19 · arxiv updated 2009/11/30
For more than a decade it was widely accepted that two-dimensional electrons are insulating at zero temperature and at zero magnetic-field. Experimentally it was demonstrated that, when placed in a strong perpendicular magnetic field, the insulating phase turns into a quantum-Hall state. While this transition was in accordance with existing theoretical models (KLZ), the density driven metal-insulator transition at zero magnetic-field, recently observed in high-quality two-dimensional systems, was unforeseen and, despite considerable amount of effort, its origins are still unknown. In order to improve our understanding of the zero magnetic-field transition, we conducted a study of the insulator to quantum-Hall transition in low-density, two-dimensional, hole system in GaAs that exhibits the zero magnetic-field metal-insulator transition. We found that, in the low field insulating phase, upon increasing the carrier density towards the metal-insulator transition, the critical magnetic-field of the insulator to quantum-Hall transition decreases and converges to the zero magnetic-field metal-insulator transition. This implies a common origin for both the finite magnetic-field and the zero magnetic-field transitions.