Superconductivity in In-doped AgSnBiTe3 with possible band inversion.

We investigated the chemical pressure effects on structural and electronic properties of SnTe-based material using partial substitution of Sn by Ag0.5Bi0.5, which results in lattice shrinkage. For Sn1-2x(AgBi)xTe, single-phase polycrystalline samples were obtained with a wide range of x. On the basis of band calculations, we confirmed that the Sn1-2x(AgBi)xTe system is basically possessing band inversion and topologically preserved electronic states. To explore new superconducting phases related to the topological electronic states, we investigated the In-doping effects on structural and superconducting properties for x = 0.33 (AgSnBiTe3). For (AgSnBi)(1-y)/3InyTe, single-phase polycrystalline samples were obtained for y = 0-0.5 by high-pressure synthesis. Superconductivity was observed for y = 0.2-0.5. For y = 0.4, the transition temperature estimated from zero-resistivity state was 2.4 K, and the specific heat investigation confirmed the emergence of bulk superconductivity. Because the presence of band inversion was theoretically predicted, and the parameters obtained from specific heat analyses were comparable to In-doped SnTe, we expect that the (AgSnBi)(1-y)/3InyTe and other (Ag, In, Sn, Bi)Te phases are candidate systems for studying topological superconductivity.

[Catecholamine Cardiomyopathy Presenting Inverted-takotsubo Pattern Asynergy].

Pheochromocytoma is complicated with catecholamine cardiomyopathy, and preoperative care becomes considerably more difficult We report anesthetic management for an 48-year-old man brought to our hospital by ambulance and immediately hospitalized due to pheochromocytoma crisis complicated with catechol- amine cardiomyopathy presenting inverted-takotsubo pattern asynergy. Before surgery, α and ß blocking drugs were used to control hypertension and tachycardia, and continuous hemodiafiltration was initiated and the patient was intubated for severe pulmonary edema. Seven days later, he underwent laparoscopic adrenalectomy. Total intravenous anesthesia was achieved with propofol, remifentanil, fentanyl, and rocuronium. During the operation, continuous infusion of landiolol, phentolamine, and nitroglycerin, and addi- tional bolus injections of landiolol were given to control hypertension. After severing the right adrenal vein, noradrenaline (0.15 µg · kg⁻¹ · min⁻¹), and dopamine (4µg · kg⁻¹ · min⁻¹) were started and the patient was placed in the intensive care unit Inverted-takotsubo pattern asynergy is not very common, and treatment consists of supportive care, as in the usual takotsubo. Preoperative CHDF (continuous hemodiafiltration) may be useful when it is difficult to control hypertension or tachycardia with medications.