In different crystals, the spin-orbit coupling effect is very important. How do you distinguish Rashba and Dresselhaus spin orbit coupling effects in different crystals?
Here are the explanation attempts:
www.physics.stackexchange.com/questions/354643/rashba-effect-vs-dresselhaus-effect-spin-orbit-coupling
www.sciencedirect.com/science/article/abs/pii/S0375960105004433
www.opscience.iop.org/article/10.1088/0953-8984/26/19/196005
www.nature.com/articles/s42005-019-0128-6
www.sciencedirect.com/science/article/pii/S1875389212011625
www.nature.com/articles/nmat4360?error=cookies_not_supported&code=4091f6cc-42aa-4d00-921c-55d805ac5600
Rashba and Dresselhaus effects both happen in systems lacking inversion symmetry. However, they occur in different environments. In the Rahsba effect, the asymmetry arises from some sorts of uniaxial anisotropy in the crystal structure. It could be due to either a net uniaxial polarity in the bulk or translational symmetry breaking at the surface or interface. The resulting gradient in potential can then induce a spin-orbit field that couples the electrons' crystalline momentum k to their spin angular momentum S at a right angle, i.e. they are always perpendicular to each other, also known as spin-momentum locking. The corresponding Hamiltonian describing the Rahaba effect in the lowest order is linear in k and described as H_R=a_R(kx.S_y – ky.S_x), where a_R is the Rehaba parameter defining the strength of the Rashba spin splitting.
On the other hand, the Dresselhaus effect happens due to a non-uniaxial Bulk inversion asymmetry. Accordingly, the resulting spin texture is not necessarily normal to the direction of momentum as in the Rehaba effect. This difference can, for example, be seen in the k-linear term of the Dresselhaus Hamiltonian H_D=b_D ( kx.Sx -ky.Sy) with b_D being the Dresselhaus parameter.
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