| Autor: |
KOTESWARARAO, B, KHUNTIA, P, KUMAR, R, MAHAJAN, AV, YOGI, A, BAENITZ, M, SKOURSKI, Y, CHOU, FC |
| Jazyk: |
angličtina |
| Rok vydání: |
2017 |
| Předmět: |
|
| Zdroj: |
IndraStra Global. |
| ISSN: |
2381-3652 |
| DOI: |
10.1103/PhysRevB.95.180407 |
| Popis: |
The structure of K2Ni2(MoO4)(3) consists of S = 1 tetramers formed by Ni2+ ions. The magnetic susceptibility chi(T) and specific heat CP (T) data on a single crystal show a broad maximum due to the low dimensionality of the system with short-range spin correlations. A sharp peak is seen in chi(T) and C-P (T) at about 1.13 K, well below the broad maximum. This is an indication of magnetic long-range order, i.e., the absence of spin gap in the ground state. Interestingly, the application of a small magnetic field (H > 0.1 T) induces magnetic behavior akin to the Bose-Einstein condensation (BEC) of triplon excitations observed in some spin-gap materials. Our results demonstrate that the temperature-field (T - H) phase boundary follows a power law (T - TN) alpha H-1/alpha with the exponent 1/alpha close to 2/3, as predicted for the BEC scenario. The observation of BEC of triplon excitations in small H infers that K2Ni2(MoO4)(3) is located in the proximity of a quantum critical point, which separates the magnetically ordered and spin-gap regions of the phase diagram. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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