X-ray waves in the center of the beam waist of nearly diffraction limited focused x-ray beams can be considered to have amplitude and phase that are both almost uniform, i.e., they are x-ray plane waves. Here we report the results of an experimental demonstration of high-resolution diffraction microscopy using the x-ray plane wave of the synchrotron x-ray beam focused using Kirkpatrik-Baez mirrors. A silver nanocube with an edge length of ϳ100 nm is illuminated with the x-ray beam focused to a ϳ1 m spot at 12 keV. A highcontrast symmetric diffraction pattern of the nanocube is observed in the forward far field. An image of the nanocube is successfully reconstructed by an iterative phasing method and its half-period resolution is 3.0 nm. This method does not only dramatically improve the spatial resolution of x-ray microscopy but also is a key technology for realizing single-pulse diffractive imaging using x-ray free-electron lasers.

Abstract. This paper reports impossible differential cryptanalysis on the 128-bit block cipher CLEFIA that was proposed in 2007, including new 9-round impossible differentials for CLEFIA, and the result of an impossible differential attack using them. For the case of a 128-bit key, it is possible to apply the impossible differential attack to CLEFIA reduced to 12 rounds. The number of chosen plaintexts required is 2 118.9 and the time complexity is 2 119 . For key lengths of 192 bits and 256 bits, it is possible to apply impossible differential attacks to 13-round and 14-round CLEFIA. The respective numbers of chosen plaintexts required are 2 119.8 and 2 120.3 and the respective time complexities are 2 146 and 2 212 . These impossible differential attacks are the strongest method for attacking reduced-round CLEFIA.

139 Mn-NMR spectra demonstrate that the ground state of the A-site ordered perovskite manganite LaBaMn2O6 is a spatial mixture of the ferromagnetic (FM) and antiferromagnetic (AFI(CE)) regions, which are assigned to the metallic and the insulating charge ordered state, respectively. This exotic coexisting state appears below 200 K via a first-order-like formation of the AFI(CE) state inside the FM one. Mn spin-spin relaxation rate indicates that the FM region coexisting with the AFI(CE) one in LaBaMn2O6 is identical to the bulk FM phase of the disordered form La0.5Ba0.5MnO3 in spite of the absence of A-site disorder. This suggests mesoscopic rather than nanoscopic nature of FM region in LaBaMn2O6.PACS numbers: 75.30. Kz; 75.25.+z; The perovskite manganites R 1−x A x MnO 3 (R = rare earth, A = Ca, Ba, Sr) have been attracting much attention for several decades, because of their rich and intriguing electromagnetic properties, such as colossal magnetoresistance (CMR), charge/orbital ordering, and metalinsulator transition. The CMR effect is believed to be a consequence of competition between double-exchange ferromagnetic metal and superexchange antiferromagnetic insulating phases. However, the estimated magnetoresistive response by the double-exchange model disagrees with the experimental data by an order of magnitude or more, suggesting the importance of another additional mechanism [1]. This discrepancy may be resolved by considering a phenomenon of phase separation, where the conduction path dominating the resistance depends on the pattern of the coexisting metallic and insulating regions [2,3]. An external magnetic field may change this pattern, and hence cause a large change in the resistivity. The phase separation is, thus, an important aspect of manganites and may be an intrinsic feature in many systems with strongly correlated electrons.Recently, half-doped manganite perovskites RBaMn 2 O 6 with the A-site order have been attracting growing interest, because the ordering of R and Ba elements at the A-site of perovskite structure dramatically modifies their phase diagram [4,5,6]. Nakajima et al. have reported that the charge ordering transition temperature is as high as 500 K with a new stacking variation with a fourfold periodicity along the c-axis for YBaMn 2 O 6 [5,7]. In addition, it is important to make clear whether the disorder at the A site plays a vital role in the occurrence of CMR or not [6]. Hence, new experimental and theoretical works have been devoted to the A-site ordered perovskite manganites to elucidate the effects of A-site order/disorder on the electromagnetic properties [8,9,10].In this paper, we focus our attention on the A-site ordered LaBaMn 2 O 6 and the disordered La 0.5 Ba 0.5 MnO 3 with the same composition. The La and Ba elements are randomly distributed at the A site of perovskite structure in La 0.5 Ba 0.5 MnO 3 . On the other hand, the structural feature of LaBaMn 2 O 6 is the alternating stack of LaO and BaO layers along the c axis with intervening MnO 2 layer. The ground s...

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