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arXiv · 1403.8073

Stability of Polarized States for Diamond Valleytronics

Johan Hammersberg·Saman Majdi·Kiran Kumar Kovi·Nattakarn Suntornwipat·Markus Gabrysch·Daniel. J. Twitchen·Jan Isberg
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Abstract

The stability of valley polarized electron states is crucial for the development of valleytronics. A long relaxation time of the valley polarization is required to enable operations to be performed on the polarized states. Here we investigate the stability of valley polarized states in diamond, expressed as relaxation time. We have found that the stability of the states can be extremely long when we consider the symmetry determined electron-phonon scattering. By Time-of-Flight measurements and Monte Carlo simulations, we determine electron-phonon coupling constants and use these data in order to map out the relaxation time temperature dependency. The relaxation time can be microseconds or longer below 100K and 100 V/cm for diamond due to the strong covalent bond, which is highly encouraging for valleytronic applications.

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Johan Hammersberg, Saman Majdi, Kiran Kumar Kovi, Nattakarn Suntornwipat, Markus Gabrysch, Daniel. J. Twitchen, Jan Isberg. 2014-03-31. Stability of Polarized States for Diamond Valleytronics. https://doi.org/10.1063/1.4882649

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