Specific heat measurements were performed on nanometer-sized particles of an S = 1/2 quantum spin system, DMACuCl3 [DMA = (CH3)2NH2]. A tiny peak was observed at a low temperature of approximately 1.5K at zero magnetic field, in addition to a well-defi ned and commonly observed peak with the bulk system at approximately 0.8 K. Under magnetic fields, it increased in intensity and coincided with the phase boundary responsible for the field-induced magnetic ordering phase above about 6 T. 1H-NMR studies confirmed that such extra peaks also indicated magnetic ordering. The resultant phase diagram is considerably different from that observed previously in the bulk system. Such a difference may be caused by the presence of extra spins found in a nanosized system by ESR measurements.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)