Incommensurate phase properties of TlGaSe₂layered crystals

Abstract

The frequency and time dependence of the ac conductivity were measured within incommensurate phase in the frequency range 10 1 -107 Hz and analyzed. The electrical conductivity decreases with decreasing temperature, then saturates in mentioned temperature interval. The ac conductivity is proportional to w s . The value f s decreases with increasing temperature which suggests hopping conduction mechanism. The time dependence of the conductivity exhibited exponential decay. It shows two conductivity relaxations in mentioned temperature interval. Moreover, the characteristic relaxation times decrease with decreasing annealing temperature. The two different relaxation times refer to two different incommensurate ordering in mentioned temperature interval.

Debye type dielectric relaxation in carbon nano-balls’ and 4-DMAABCA acid doped E7 coded nematic liquid crystal

“…To characterize the dielectric relaxation occurring in mentioned temperature interval, ColeCole's circular arc law was applied to the results of e 0 and e 00 . The shape of the relaxation was studied by fitting the experimental data to the following phenomenological equations [27]:…”

Temperature dependency of impedance spectroscopy behaviors in side-chain liquid crystalline polymer

“…The power law dependence of the AC conductivity on frequency is of a universal nature and it corresponds to the short range hopping of charge carriers through trap sites that are separated by energy barriers of varied heights [28]. The values of the power exponent were found to decrease slowly with increasing temperature indeed.…”

PRESSURE BEHAVIOUR OF DIELECTRIC PERMEABILITY IN TlGaSe2 CRYSTALS

“…Äîñë³äaeåííÿ ³íäóêîâàíèõ òèñêîì ô³çè÷íèõ åôåêò³â ó ñêëàäíèõ ôåðî¿êàõ ð³çíî¿ âèì³ðíîñò³ äàþòü ìîaeëèâ³ñòü ãëèáøå ïðîíèêíóòè â ïðèðîäó âèíèêíåííÿ íåñï³âì³ðíî-ìîäóëüîâàíèõ ñòðóêòóð ³ ïîÿâè íà ¿õ ä³àãðàìàõ ñòàíó ïîë³êðè-òè÷íèõ òî÷îê òà äîçâîëÿþòü ö³ëåñïðÿìîâàíî ïðîâîäèòè ïîøóê ìàòåð³àë³â äëÿ ðîçðîáêè íà ¿õ îñíîâ³ ôóíêö³îíàëüíèõ åëåìåíò³â äëÿ âèì³-ðþâà÷³â òèñêó, òåìïåðàòóðè, ï³ðîåëåêòðè÷íèõ ïðèéìà÷³â åëåêòðîìàãí³òíîãî âèïðîì³íþâàííÿ. Äî òàêîãî êëàñó ìàòåð³àë³â íàëåaeàòü ³ øàðó-âàò³ êðèñòàëè TlGaSe 2 , â ÿêèõ ³ñíóº íåñï³âì³ðíà ôàçà ó ³íòåðâàë³ òåìïåðàòóð 107-116 Ê [1][2][3][4].…”