Controlling mesoscopic phase separation near electronic topological transitions via quenched disorder in ternary diborides

Palmisano, V; Simonelli, L; Puri, A; Fratini, M; Busby, Y; Parisiades, P; Liarokapis, E; Brunelli, M; Fitch, AN; Bianconi, A

dc.contributor.author	Palmisano, V	en
dc.contributor.author	Simonelli, L	en
dc.contributor.author	Puri, A	en
dc.contributor.author	Fratini, M	en
dc.contributor.author	Busby, Y	en
dc.contributor.author	Parisiades, P	en
dc.contributor.author	Liarokapis, E	en
dc.contributor.author	Brunelli, M	en
dc.contributor.author	Fitch, AN	en
dc.contributor.author	Bianconi, A	en
dc.date.accessioned	2014-03-01T01:28:04Z
dc.date.available	2014-03-01T01:28:04Z
dc.date.issued	2008	en
dc.identifier.issn	0953-8984	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/18701
dc.subject	Phase Separation	en
dc.subject	Quenched Disorder	en
dc.subject	Electronic Topological Transition	en
dc.subject.classification	Physics, Condensed Matter	en
dc.subject.other	Borides	en
dc.subject.other	Diffraction	en
dc.subject.other	Electromagnetic waves	en
dc.subject.other	Electron gas	en
dc.subject.other	Equations of state	en
dc.subject.other	Isomers	en
dc.subject.other	Magnesium printing plates	en
dc.subject.other	Metastable phases	en
dc.subject.other	Phase modulation	en
dc.subject.other	Separation	en
dc.subject.other	Superconducting materials	en
dc.subject.other	Topology	en
dc.subject.other	C -axis	en
dc.subject.other	Critical points	en
dc.subject.other	Diborides	en
dc.subject.other	Electronic topological transitions	en
dc.subject.other	Feshbach	en
dc.subject.other	High resolutions	en
dc.subject.other	Interband	en
dc.subject.other	Lattice disorders	en
dc.subject.other	Mesoscopic	en
dc.subject.other	Physical variables	en
dc.subject.other	Powder diffractions	en
dc.subject.other	Quenched disorders	en
dc.subject.other	Raman datums	en
dc.subject.other	Random distributions	en
dc.subject.other	Rich phase	en
dc.subject.other	Shape resonances	en
dc.subject.other	Superconducting critical temperatures	en
dc.subject.other	X-ray diffractions	en
dc.subject.other	Phase separation	en
dc.title	Controlling mesoscopic phase separation near electronic topological transitions via quenched disorder in ternary diborides	en
heal.type	journalArticle	en
heal.identifier.primary	10.1088/0953-8984/20/43/434222	en
heal.identifier.secondary	http://dx.doi.org/10.1088/0953-8984/20/43/434222	en
heal.identifier.secondary	434222	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	A phase separation driven by the negative compressibility of the electron gas, near electronic topological transitions (ETT), could drive the system at the verge of a catastrophe. We show here that the metastable phases very close to the ETT transition are observed in a mesoscopic phase separation (MePhS) driven by the quenched lattice disorder. By using high resolution synchrotron radiation x-ray powder diffraction we have identified the MePhS for the intermetallic ternary Mg1-xAlxB2 in the proximity of two ETTs: the first at x1 = 0.1 and the second at x 2 = 0.3. We have identified the competition between a first 'relaxed' (R) hole poor and a second 'tense' (T) hole rich phase, and by micro-Raman we observe the splitting of the in-plane phonon E2g mode in the proximity of the first ETT at x = 0.1. The anisotropic quenched disorder due to a random distribution of Al3+ and Mg2+ ions both in the axial (c axis) direction and planar (ab plane) direction, probed by x-ray diffraction and Raman data, is proposed to be the physical variable that allows the formation of metastable phases near the critical points of electronic topological transitions, where Feshbach shape resonances in interband pairing amplifies the superconducting critical temperature. © 2008 IOP Publishing Ltd.	en
heal.publisher	IOP PUBLISHING LTD	en
heal.journalName	Journal of Physics Condensed Matter	en
dc.identifier.doi	10.1088/0953-8984/20/43/434222	en
dc.identifier.isi	ISI:000259922600023	en
dc.identifier.volume	20	en
dc.identifier.issue	43	en