Dichalcogenides

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Phase Diagramme of transition metal dicalcogenides 1T-TaS2. The melting of the Mott-phase is followed by superconductivity.

 

Artistic view of the 2D planes decorated with CDWs in form of David stars.

Another original dichalcogenide system, subject of our investigations is Co0.33NbS2. Within the NbS2, layers intercalated Co forms a triangular lattice with an antiferromagnetic (AFM) order. The magnetism strongly influences the 2D elctronic transport. The application suppresses the AFM order and drives the system through the Doniach phase diagram, from the RKKY to Kondo  dominated interactions.

References:
[1] N. Barišić, I. Smiljanić, P. Popčević, A. Bilušić and E. Tutiš, A. Smontara, H. Berger, J. Jaćimović,O. Yuli, and L. Forró, High-pressure study of transport properties in Co0.33NbS2, Physical Review B, vol. 84, (2011).
[2] A. F. Kusmartseva, B. Sipos, H. Berger, L. Forró , and E. Tutiš, Pressure induced superconductivity in pristine 1T-TiSe2, Physical Review Letters 103, 236401 (2009).
[3] B. Sipos, A. F. Kusmartseva, A. Akrap, H. Berger, L. Forró & E. Tutiš, From Mott state to superconductivity in 1T-TaS2, Nature Materials 7, 960 – 965 (2008).