Fermionic order by disorder in a van der Waals antiferromagnet.

CeTe3 is a unique platform to investigate the itinerant magnetism in a van der Waals (vdW) coupled metal. Despite chemical pressure being a promising route to boost quantum fluctuation in this system, a systematic study on the chemical pressure effect on Ce3+(4f1) states is absent. Here, we report on the successful growth of a series of Se doped single crystals of CeTe3. We found a fluctuation driven exotic magnetic rotation from the usual easy-axis ordering to an unusual hard-axis ordering. Unlike in localized magnetic systems, near-critical magnetism can increase itinerancy hand-in-hand with enhancing fluctuation of magnetism. Thus, seemingly unstable hard-axis ordering emerges through kinetic energy gain, with the self-consistent observation of enhanced magnetic fluctuation (disorder). As far as we recognize, this order-by-disorder process in fermionic system is observed for the first time within vdW materials. Our finding opens a unique experimental platform for direct visualization of the rich quasiparticle Fermi surface deformation associated with the Fermionic order-by-disorder process. Also, the search for emergent exotic phases by further tuning of quantum fluctuation is suggested as a promising future challenge.

A series of magnon crystals appearing under ultrahigh magnetic fields in a kagomé antiferromagnet.

Geometrical frustration and a high magnetic field are two key factors for realizing unconventional quantum states in magnetic materials. Specifically, conventional magnetic order can potentially be destroyed by competing interactions and may be replaced by an exotic state that is characterized in terms of quasiparticles called magnons, the density and chemical potential of which are controlled by the magnetic field. Here we show that a synthetic copper mineral, Cd-kapellasite, which comprises a kagomé lattice consisting of corner-sharing triangles of spin-1/2 Cu2+ ions, exhibits an unprecedented series of fractional magnetization plateaus in ultrahigh magnetic fields of up to 160 T. We propose that these quantum states can be interpreted as crystallizations of emergent magnons localized on the hexagon of the kagomé lattice.

Radiologic findings in xanthogranulomatous cholecystitis.

Xanthogranulomatous cholecystitis is rare, and information on its radiologic diagnosis is limited. Radiologic findings of seven patients with histologically proven xanthogranulomatous cholecystitis were reviewed retrospectively. Sonography showed a calculus or calculi of the gallbladder with moderate thickening of the wall in all. IV cholangiography was performed in six cases. Findings were nonspecific. Four had nonopacified gallbladder, and one had stenosis of the proximal part of the common bile duct. Marked thickening of the gallbladder wall was seen in six of seven cases on CT. In one case the thickened wall was lobulated and irregular. The border between the gallbladder and the adjacent liver was unclear in two and relatively clear in five. Four patients underwent angiography to evaluate the possibility of tumor. Two of them had irregularity and stenosis of the cystic artery highly suggestive of carcinoma. The other two showed only dilatation of the cystic artery. On the basis of all radiologic studies, carcinoma was diagnosed preoperatively in two of the seven cases. Radiologically, xanthogranulomatous cholecystitis may best be regarded as a tumor-like condition and should be included in the differential diagnosis of gallbladder cancer.

[A case of inferior vena cava thrombosis associated with cholelithiasis demonstrated by ultrasonic examination].

A case of a 44 year old female with inferior vena cava thrombosis associated with cholelithiasis was reported. The patient had chest and back pain due to pulmonary embolism. Ultrasonic examination showed stone echoes in the gallbladder and thrombus echoes in the inferior vena cava (IVC) at the height from renal veins to bifurcation of iliac veins, but iliofemoral thrombosis was not found by RI angiography and venography. Anticoagulant and urokinase were administered, then pulmonary embolus disappeared and IVC thrombus reduced. IVC thrombus was removed by incision of IVC. Thrombus was white thrombus. Etiology of thrombus was not clear. IVC ligation or plication for prevention of pulmonary emboli was not carried out. Etiology, diagnosis and treatment of IVC thrombosis were also discussed.