Acoustic and acousto-optic properties of Ge-=SUB=-a-=/SUB=-Se-=SUB=-b-=/SUB=-Te-=SUB=-c-=/SUB=- and Si-=SUB=-a-=/SUB=-Se-=SUB=-b-=/SUB=-Te-=SUB=-c-=/SUB=- glasses in case diffraction on longitudinal and shear acoustic waves

Toward the Ultimate Limit of Phase Change in Ge₂Sb₂Te₅

The limit to which the phase change memory material Ge2Sb2Te5 can be scaled toward the smallest possible memory cell is investigated using structural and optical methodologies. The encapsulation material surrounding the Ge2Sb2Te5 has an increasingly dominant effect on the material’s ability to change phase, and a profound increase in the crystallization temperature is observed when the Ge2Sb2Te...

Exotic Topological Insulator States and Topological Phase Transitions in Sb₂Se₃Bi₂Se₃ Heterostructures

C 2012 American Chemical Society Exotic Topological Insulator States and Topological Phase Transitions in Sb2Se3 Bi2Se3 Heterostructures Qianfan Zhang, Zhiyong Zhang, Zhiyong Zhu, Udo Schwingenschlögl, and Yi Cui* Department of Material Sciences and Engineering and Stanford Nanofabrication Facility, Stanford University, Stanford, California 94305, United States, PSE Division, KAUST, Thuwal 2395...

Formal group law homomorphisms over <i>O</i>_{<b>C</b>_p}

Let K be a finite extension of the p-adic field Qp and let F (X,Y ) and G(X, Y ) be one-dimensional formal group laws over the ring of integers OK of K. Let φ(X) be a homomorphism from F to G which is defined over the ring of integers OCp of the completion Cp of Q p . In this paper we prove that if ker(φ) is finite then there is a discretely valued subfield L ⊂ Cp such that φ(X) is defined over...

Magnetic and electronic properties of Eu₄Sr₄Ga₁₆Ge₃₀

Magnetic properties of the Haldane-gap material [Ni(C₂H₈N₂)₂NO₂](BF₄)

Results of magnetization and high-field electron spin resonance (ESR) studies of the new spin-1 Haldane-chain material [Ni(C2H8N2)2NO2] (BF4) (NENB) are reported. A definite signature of the Haldane state in NENB was obtained. From the analysis of the frequency–field dependence of magnetic excitations in NENB, the spin-Hamiltonian parameters were calculated, yielding 1/kB = 17.4 K, g‖ = 2.14, D...