Lithuanian Journal of Physics article / Lietuvos fizikos žurnalo straipsnis

[PDF] http://dx.doi.org/10.3952/lithjphys.49205

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 49, 209–214 (2009)

TEMPERATURE BEHAVIOUR OF OPTICAL ABSORPTION EDGE AND PHASE TRANSITIONS IN Cu₆PS₅I₀_.₈Cl₀_.₂ SUPERIONIC MIXED CRYSTALS
I.P. Studenyak^a, V.Yu. Izai^a, V.V. Panko^b, A.F. Orliukas^b, E. Kazakevičius^b, F. Koleli^c, M. Dudukcu^c, and R. Aydin^c
^aUzhhorod National University, 46 Pidhirna St, 88000 Uzhhorod, Ukraine
E-mail: studenyak@dr.com
^bFaculty of Physics, Vilnius University, Saulėtekio 9, LT-10222 Vilnius, Lithuania
^cMersin University, Ciftlik-koy, 33342 Mersin, Turkey

Received 28 January 2009; revised 16 March 2009; accepted 19 March 2009

Isoabsorption and spectral temperature studies of absorption edge of Cu₆PS₅I₀_.₈Cl₀_.₂ superionic mixed crystals are performed. Phase transition temperatures are determined and the transitions are identified. The optical absorption edge shape is studied in the temperature range 77–320 K, the parameters of electron-phonon interaction, resulting in the Urbach behaviour of the optical absorption edge, are determined, temperature dependences of the optical pseudogap and Urbach energy are obtained.

Keywords: superionic mixed crystals, optical absorption edge, Urbach rule, phase transitions

PACS: 78.40.Ha, 77.80.Bh

OPTINIO SUGERTIES KRAŠTO TEMPERATŪRINIS ELGESYS IR FAZINIAI VIRSMAI Cu₆PS₅I_0,8Cl_0,2 SUPERJONINIAME LAIDININKE

I.P. Studenyak^a, V.Yu. Izai^a, V.V. Panko^b, A.F. Orliukas^b, E. Kazakevičius^b, F. Koleli^c, M. Dudukcu^c, R. Aydin^c
^aUžhorodo nacionalinis universitetas, Užhorodas, Ukraina
^bVilniaus universiteto Fizikos fakultetas, Vilnius, Lietuva
^cMersino universitetas, Mersinas, Turkija

Atlikti maišyto Cu₆PS₅I_0,8Cl_0,2 kristalo izosugerties ir sugerties krašto spektriniai bei temperatūriniai tyrimai, identifikuoti faziniai virsmai ir įvertintos jų temperatūros. Optinės sugerties krašto forma buvo tiriama 77–300 K temperatūroje, nustatyti optinės sugerties krašto Urbacho elgesį lemiančios elektrono ir fonono sąveikos parametrai bei optinio pseudotarpo ir Urbacho energijos temperatūrinės priklausomybės.

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