On the puzzling low-temperature phenomena in SmRu4P12

Pressure effect on elastic properties in

“…In addition, we found T MI increases with applying pressure, showing a large Gru¨neisen parameter of O ¼ 12 [11]. Previous studies show that the T MI has a normal O of about 1, while the T N has a very large one of 28 [12]. The observed O is between the two, suggestive of a strong interplay between the two transitions.…”

Anomalous elastic softening ofSmRu4P12under high pressure

“…The considerably large Ω is reminiscent of the two very different Grüneisen parameters estimated for T MI and T N [23]. The conventional equation Ω = C B β/C (here β is volume thermal expansion coefficient and C specific heat) gives a huge Ω = 28 for T N , but a normal Ω = 1 for T MI .…”

“…(2) We intend to build a pressure-temperature (P -T ) phase diagram from which to gain knowledge of the OPs of phase II and III. (3) One more point of interest is the very different Grüneisen parameters Ω of T MI and T N , the latter being much larger than the former [23]. Widely different Grüneisen parameters suggest different pressure dependencies of the two phase transitions, and prompted us to explore the physical properties under hydrostatic pressures related to this phenomenon.…”

Strange Elastic Properties and Possible Octupolar Ordering in SmRu4P12

“…∂ e , are 1.1 and 28, respectively. 20 These value correspond to g ψ = -17 K and g m = -342 K. The small value of g ψ makes some contribution to the softening behavior in phase II, because g ψ produces a small jump at T MI . We adopted these values for shear strain, because the Grüneisen parameter for shear strain has not been known.…”