2003/01/22 by T. Imai, Imai, T., F. C. Chou +1
Physics and Astronomy · #FOS: Physical sciences #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.cond-mat/0301425
4 pages and 3 figures
arxiv created 2003/01/22 · arxiv updated 2009/11/30
We have investigated the spin fluctuations and their interplay with lattice instabilities in a layered S=1/2 quantum spin system TiOCl. Our Ti and Cl NMR data demonstrate a pseudo spin-gap behavior below T*=135 K, followed by successive phase transitions at Tc1=94K and Tc2=66K into the singlet ground state with an unusually large energy gap Eg=430K. The broad distribution of the local electric field gradient in the intermediate phase between Tc1 and Tc2 suggests unconventional spin and lattice (probably orbital) states with an emerging spin-gap.