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Spin-valley phase diagram of the two-dimensional metal-insulator transition

O. Gunawan·T. Gokmen·K. Vakili·M. Padmanabhan·E. P. De Poortere·M. Shayegan
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Abstract

Using symmetry breaking strain to tune the valley occupation of a two-dimensional (2D) electron system in an AlAs quantum well, together with an applied in-plane magnetic field to tune the spin polarization, we independently control the system's valley and spin degrees of freedom and map out a spin-valley phase diagram for the 2D metal-insulator transition. The insulating phase occurs in the quadrant where the system is both spin- and valley-polarized. This observation establishes the equivalent roles of spin and valley degrees of freedom in the 2D metal-insulator transition.

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O. Gunawan, T. Gokmen, K. Vakili, M. Padmanabhan, E. P. De Poortere, M. Shayegan. 2006-09-20. Spin-valley phase diagram of the two-dimensional metal-insulator transition. https://doi.org/10.1038/nphys596

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