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We have carried out a powder X-ray diffraction investigation on antiferromagnetic Kondo semiconductorsCeRu2Al10 and CeOs2Al10 at low temperatures and under high pressures as well as the structural investigationon single crystal of these compounds. The results of powder X-ray studies of CeRu2Al10 and CeOs2Al10 indicatethat these compounds do not have structural transition at its antiferromagnetic ordering temperature. The resultsof single crystal structural refinement indicate that the b-axis of this crystal structure is insensitive not only topressure but also to temperature and that the effect of cooling to Ce–Ce distance for CeRu2Al10 is the same asthat for CeOs2Al10.

We have carried out a powder X-ray diffraction investigation on antiferromagnetic Kondo semiconductorsCeRu2Al10 and CeOs2Al10 at low temperatures and under high pressures as well as the structural investigationon single crystal of these compounds. The results of powder X-ray studies of CeRu2Al10 and CeOs2Al10 indicatethat these compounds do not have structural transition at its antiferromagnetic ordering temperature. The resultsof single crystal structural refinement indicate that the b-axis of this crystal structure is insensitive not only topressure but also to temperature and that the effect of cooling to Ce–Ce distance for CeRu2Al10 is the same asthat for CeOs2Al10.

We have carried out a powder X-ray diffraction investigation on antiferromagnetic Kondo semiconductorsCeRu2Al10 and CeOs2Al10 at low temperatures and under high pressures as well as the structural investigationon single crystal of these compounds. The results of powder X-ray studies of CeRu2Al10 and CeOs2Al10 indicatethat these compounds do not have structural transition at its antiferromagnetic ordering temperature. The resultsof single crystal structural refinement indicate that the b-axis of this crystal structure is insensitive not only topressure but also to temperature and that the effect of cooling to Ce–Ce distance for CeRu2Al10 is the same asthat for CeOs2Al10.

We have carried out a powder X-ray diffraction investigation on antiferromagnetic Kondo semiconductorsCeRu2Al10 and CeOs2Al10 at low temperatures and under high pressures as well as the structural investigationon single crystal of these compounds. The results of powder X-ray studies of CeRu2Al10 and CeOs2Al10 indicatethat these compounds do not have structural transition at its antiferromagnetic ordering temperature. The resultsof single crystal structural refinement indicate that the b-axis of this crystal structure is insensitive not only topressure but also to temperature and that the effect of cooling to Ce–Ce distance for CeRu2Al10 is the same asthat for CeOs2Al10.

We have investigated low-temperature elastic properties of PrMg3 with a non-Kramers Gamma3 doublet ground state using ultrasonic measurements. Although the Gamma3 doublet possesses electric quadrupoles Ou and Ov with Gamma3-symmetry and magnetic octupole Txyz with Gamma2, PrMg3 reveals no sign of symmetry breaking long-range ordering down to 20 mK. [1] The elastic constant of (C11-C12)/2 in PrMg3 exhibits remarkable softening below 8 K, which is well described in terms of a Curie-type quadrupole susceptibility for the Gamma3 doublet. An appreciable upturn in (C11-C12)/2 below 800 mK in PrMg3 may indicate an transition into an exotic ground state due to the quadrupole Kondo state being screened by conduction electrons. Frequency dependence in (C11-C12)/2 and its attenuation coefficients at low temperature in PrMg3 suggests quadrupole fluctuations possessing a characteristic relaxation time tau = tau0exp(E/kT) with tau0 = 6x10-11 sec and an activation energy E = 410 mK. The low-temperature behavior in (C11-C12)/2 of PrMg3 under magnetic fields is also presented.

We have investigated low-temperature elastic properties of PrMg3 with a non-Kramers Gamma3 doublet ground state using ultrasonic measurements. Although the Gamma3 doublet possesses electric quadrupoles Ou and Ov with Gamma3-symmetry and magnetic octupole Txyz with Gamma2, PrMg3 reveals no sign of symmetry breaking long-range ordering down to 20 mK. [1] The elastic constant of (C11-C12)/2 in PrMg3 exhibits remarkable softening below 8 K, which is well described in terms of a Curie-type quadrupole susceptibility for the Gamma3 doublet. An appreciable upturn in (C11-C12)/2 below 800 mK in PrMg3 may indicate an transition into an exotic ground state due to the quadrupole Kondo state being screened by conduction electrons. Frequency dependence in (C11-C12)/2 and its attenuation coefficients at low temperature in PrMg3 suggests quadrupole fluctuations possessing a characteristic relaxation time tau = tau0exp(E/kT) with tau0 = 6x10-11 sec and an activation energy E = 410 mK. The low-temperature behavior in (C11-C12)/2 of PrMg3 under magnetic fields is also presented.

We present a new exact black hole solution in three dimensional Einstein gravity coupled to a single scalar field. This is one of the extended solutions of the BTZ black hole and has in fact $\textrm{AdS}_3$ geometries both at the spatial infinity and at the event horizon. An explicit derivation of Virasoro algebras for $\textrm{CFT}_2$ at the two boundaries is shown to be possible \`{a} la Brown and Henneaux's calculation. If we regard the scalar field as a running coupling in the dual two dimensional field theory, and its flow in the bulk as the "holographic" renormalization group flow, our black hole should interpolate the two $\textrm{CFT}_2$ living at the infinity and at the horizon. Following the Hamilton-Jacobi analysis by de Boer, Verlinde and Verlinde, we calculate the central charges $c_{\textrm{UV}}$ and $c_{\textrm{IR}}$ for the $\textrm{CFT}_2$ on the infinity and the horizon, respectively. We also confirm that the inequality $c_{\textrm{IR}} < c_{\textrm{UV}}$ is satisfied, which is consistent with the Zamolodchikov's c-theorem., Comment: 20 pages, 2 figures, references added

We present a new exact black hole solution in three dimensional Einstein gravity coupled to a single scalar field. This is one of the extended solutions of the BTZ black hole and has in fact $\textrm{AdS}_3$ geometries both at the spatial infinity and at the event horizon. An explicit derivation of Virasoro algebras for $\textrm{CFT}_2$ at the two boundaries is shown to be possible \`{a} la Brown and Henneaux's calculation. If we regard the scalar field as a running coupling in the dual two dimensional field theory, and its flow in the bulk as the "holographic" renormalization group flow, our black hole should interpolate the two $\textrm{CFT}_2$ living at the infinity and at the horizon. Following the Hamilton-Jacobi analysis by de Boer, Verlinde and Verlinde, we calculate the central charges $c_{\textrm{UV}}$ and $c_{\textrm{IR}}$ for the $\textrm{CFT}_2$ on the infinity and the horizon, respectively. We also confirm that the inequality $c_{\textrm{IR}} < c_{\textrm{UV}}$ is satisfied, which is consistent with the Zamolodchikov's c-theorem., Comment: 20 pages, 2 figures, references added