Magnetic and transport properties of layered Li_xCoO₂single crystals

Magnetic and electronic properties ofLixCoO2single crystals

“…These behaviors have been similarly observed in earlier studies. [10][11][12][13][14][15] Also it is found that there is no difference in the M FC ͑T͒ and M ZFC ͑T͒ curves after slow cool but the M͑T͒ curves after slow and rapid cool exhibit a splitting below T F ϳ 130 K. The characteristic behaviors of the M͑T͒ curve for x = 0.71 are similarly observed for x = 0.66 and 0.46 as seen in Figs. 4͑b͒ and 4͑c͒.…”

“…In the previous work, single crystals of LiCoO 2 were grown in an optical floating-zone furnace, 14 whereas in the present work those were obtained by an ion exchange reaction between Li 2 CO 3 and Na 0.75 CoO 2 single crystals, which are easier to obtain than LiCoO 2 single crystals. The singlecrystal growth of Na 0.75 CoO 2 was performed in a similar manner as described in the literature.…”

“…It has been reported that electrical resistivity near room temperature decreases abruptly with decreasing x from 1 to ϳ0.9, 9,10 indicating a transition from insulator to metal. For Li x CoO 2 , a sharp decrease in dc magnetization [10][11][12][13][14][15] and increase in resistivity 7 have been observed below 160-170 K with wide range of Li content. This transition is of first order 14,15 and the occurrence of charge ordering in CoO 2 layers has been suggested.…”

“…For Li x CoO 2 , a sharp decrease in dc magnetization [10][11][12][13][14][15] and increase in resistivity 7 have been observed below 160-170 K with wide range of Li content. This transition is of first order 14,15 and the occurrence of charge ordering in CoO 2 layers has been suggested. 12,15 The fully delithiated com-pound CoO 2 ͑x =0͒, which is also the end member of Na x CoO 2 , has been found to be a Pauli paramagnetic metal without electron correlation due to the lack of two dimensionality in the structure contrasting to A x CoO 2 ͑A =Li,Na͒.…”

Electronic phase diagram of the layered cobalt oxide systemLixCoO2(0.0≤xMotohashi1, Ono2, Sugimoto3 et al. 2009Phys. Rev. B828800View full textAdd to dashboardCite

“…The x = 0.50 sample also shows a magnetic jump at about 175 K, as reported previously. [29][30][31] However, the feature is somewhat different from that of x = 0.67 and 0.70: the hysteresis width is much larger for x = 0.50 ͑⌬T Ϸ 20 K͒ than for x = 0.67 and 0.70. Importantly, it appears that the magnetic anomaly at T t Ϸ 175 K is absent in the sample with an intermediate Li composition, i.e., x = 0.60.…”