Spin Hall Effect of Excitons

Spin Hall effect for excitons in alkali halides and in Cu_2O is investigated theoretically. In both systems, the spin Hall effect results from the Berry curvature in k space, which becomes nonzero due to lifting of degeneracies of the exciton states by exchange coupling. The trajectory of the excitons can be directly seen as spatial dependence of the circularly polarized light emitted from the excitons. It enables us to observe the spin Hall effect directly in the real-space time.Comment: 5 pages, 2 figure

Investigation of the thermal expansion and heat capacity of the CaCu3Ti4O12 ceramics

The thermal expansion of the CaCu3Ti4O12 ceramics has been measured over a wide temperature range 120–1200 K. The high quality of the samples under study has been confirmed by good agreement of the results of measurements of the heat capacity in the range 2–300 K and in the vicinity of the phase transition of magnetic nature at 25 K with the data for the single crystal. No anomalies in the thermal expansion that can be associated with the phase transition at 726–732 K assumed by other investigators have been found. The influence exerted on the thermal expansion by the heat treatment of the sample in a helium atmosphere and in air has been investigated

Cluster galaxies 10 billion years ago

Cl J1449+0856 is a spectroscopically confirmed galaxy cluster at z ~ 2. The detection of a faint, extended X-ray emission, suggestive of an already evolved, partially relaxed structure, puts this system among the most distant "established” clusters rather than in the realm of z≳2 proto-clusters. This gives us a chance of studying galaxies in an evolved overdense environment very close to their formation epoch, and in particular to trace the evolution of early-type galaxies in clusters back to ten billion years ag

Magnetic Phase Diagrams with Possible Field-induced Antiferroquadrupolar Order in TbB2_2C2_2

Magnetic phase diagrams of a tetragonal antiferromagnet TbB$_2$C$_2$ were clarified by temperature and field dependence of magnetization. It is noticeable that the N{\'e}el temperature in TbB$_2$C$_2$ is anomalously enhanced with magnetic fields, in particular the enhancement reaches 13.5 K for the ${}$ direction at 10 T. The magnetization processes as well as the phase diagrams are well interpreted assuming that there appear field-induced antiferroquadrupolar ordered phases in TbB$_2$C$_2$. The phase diagrams of the AFQ compounds in RB$_2$C$_2$ are systematically understood in terms of the competition with AFQ and AFM interactions.Comment: 4 pages, 4 figures, RevTeX

Wide-Supply-Range All-Digital Leakage Variation Sensor for On-Chip Process and Temperature Monitoring

Variation in process, voltage and temperature is a major obstacle in achieving energy-efficient operation of LSI. This paper proposes an all-digital on-chip circuit to monitor leakage current variations of both of the nMOSFET and pMOSFET independently. As leakage current is highly sensitive to threshold voltage and temperature, the circuit is suitable for tracking process and temperature variation. The circuit uses reconfigurable inhomogeneity to obtain statistical properties from a single monitor instance. A compact reconfigurable inverter topology is proposed to implement the monitor circuit. The compact and digital nature of the inverter enables cell-based design, which will reduce design costs. Measurement results from a 65 nm test chip show the validity of the proposed circuit. For a 124 sample size for both of the nMOSFET and pMOSFET, the monitor area is 4500 μm2 and active power consumption is 76 nW at 0.8 V operation. The proposed technique enables area-efficient and low-cost implementation thus can be used in product chips for applications such as dynamic energy and thermal management, testing and post-silicon tuning