Details

Autor(en) / Beteiligte

• Suzuki, R
• Sakano, M
• Zhang, Y J
• Akashi, R
• Morikawa, D
• Harasawa, A
• Yaji, K
• Kuroda, K
• Miyamoto, K
• Okuda, T
• Ishizaka, K
• Arita, R
• Iwasa, Y

Titel

Valley-dependent spin polarization in bulk MoS2 with broken inversion symmetry

Ist Teil von

• Nature nanotechnology, 2014-08, Vol.9 (8), p.611-617

Ort / Verlag

England: Nature Publishing Group

Erscheinungsjahr

2014

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The valley degree of freedom of electrons is attracting growing interest as a carrier of information in various materials, including graphene, diamond and monolayer transition-metal dichalcogenides. The monolayer transition-metal dichalcogenides are semiconducting and are unique due to the coupling between the spin and valley degrees of freedom originating from the relativistic spin-orbit interaction. Here, we report the direct observation of valley-dependent out-of-plane spin polarization in an archetypal transition-metal dichalcogenide--MoS2--using spin- and angle-resolved photoemission spectroscopy. The result is in fair agreement with a first-principles theoretical prediction. This was made possible by choosing a 3R polytype crystal, which has a non-centrosymmetric structure, rather than the conventional centrosymmetric 2H form. We also confirm robust valley polarization in the 3R form by means of circularly polarized photoluminescence spectroscopy. Non-centrosymmetric transition-metal dichalcogenide crystals may provide a firm basis for the development of magnetic and electric manipulation of spin/valley degrees of freedom.