Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE>
Intercalated nanostructures of InSe<htd> and GaSe<htd> are fabricated. Сформовано інтеркалянтні наноструктури InSe<htd> та GaSe<htd>. Сформированы интеркалянтные наноструктуры InSe<htd> и GaSe<htd>....
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Інститут металофізики ім. Г.В. Курдюмова НАН України
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Ivashchyshyn, F.O. Grygorchak, I.I. Klapchuk, M.I. 2016-10-17T15:32:19Z 2016-10-17T15:32:19Z 2015 Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE> / F.O. Ivashchyshyn, I.I. Grygorchak, M.I. Klapchuk // Наносистеми, наноматеріали, нанотехнології: Зб. наук. пр. — К.: РВВ ІМФ, 2015. — Т. 13, № 3. — С. 403-414. — Бібліогр.: 10 назв. — англ. 1816-5230 PACS numbers: 71.20.Tx, 77.84.-s, 81.07.Pr, 81.16.Fg, 82.75.-z, 84.32.Tt, 84.37.+q https://nasplib.isofts.kiev.ua/handle/123456789/107287 Intercalated nanostructures of InSe<htd> and GaSe<htd> are fabricated. Сформовано інтеркалянтні наноструктури InSe<htd> та GaSe<htd>. Сформированы интеркалянтные наноструктуры InSe<htd> и GaSe<htd>. en Інститут металофізики ім. Г.В. Курдюмова НАН України Наносистеми, наноматеріали, нанотехнології Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE> Article published earlier |
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Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE> |
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Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE> Ivashchyshyn, F.O. Grygorchak, I.I. Klapchuk, M.I. |
| title_short |
Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE> |
| title_full |
Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE> |
| title_fullStr |
Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE> |
| title_full_unstemmed |
Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE> |
| title_sort |
impedance anisotropy and quantum photocapacity of bio/inorganic clathrates inse<histidine> and gase<histidine> |
| author |
Ivashchyshyn, F.O. Grygorchak, I.I. Klapchuk, M.I. |
| author_facet |
Ivashchyshyn, F.O. Grygorchak, I.I. Klapchuk, M.I. |
| publishDate |
2015 |
| language |
English |
| container_title |
Наносистеми, наноматеріали, нанотехнології |
| publisher |
Інститут металофізики ім. Г.В. Курдюмова НАН України |
| format |
Article |
| description |
Intercalated nanostructures of InSe<htd> and GaSe<htd> are fabricated.
Сформовано інтеркалянтні наноструктури InSe<htd> та GaSe<htd>.
Сформированы интеркалянтные наноструктуры InSe<htd> и GaSe<htd>.
|
| issn |
1816-5230 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/107287 |
| citation_txt |
Impedance Anisotropy and Quantum Photocapacity of Bio/Inorganic Clathrates InSe<HISTIDINE> and GaSe<HISTIDINE> / F.O. Ivashchyshyn, I.I. Grygorchak, M.I. Klapchuk // Наносистеми, наноматеріали, нанотехнології: Зб. наук. пр. — К.: РВВ ІМФ, 2015. — Т. 13, № 3. — С. 403-414. — Бібліогр.: 10 назв. — англ. |
| work_keys_str_mv |
AT ivashchyshynfo impedanceanisotropyandquantumphotocapacityofbioinorganicclathratesinsehistidineandgasehistidine AT grygorchakii impedanceanisotropyandquantumphotocapacityofbioinorganicclathratesinsehistidineandgasehistidine AT klapchukmi impedanceanisotropyandquantumphotocapacityofbioinorganicclathratesinsehistidineandgasehistidine |
| first_indexed |
2025-11-24T02:16:43Z |
| last_indexed |
2025-11-24T02:16:43Z |
| _version_ |
1850836666909982720 |
| fulltext |
403
PACS numbers: 71.20.Tx, 77.84.-s, 81.07.Pr, 81.16.Fg, 82.75.-z, 84.32.Tt, 84.37.+q
Impedance Anisotropy and Quantum Photocapacity
of Bio/Inorganic Clathrates InSe<HISTIDINE> and
GaSe<HISTIDINE>
F. O. Ivashchyshyn, I. I. Grygorchak, and M. I. Klapchuk
Lviv Polytechnic National University,
12 S. Bandera Str.,
79013 Lviv, Ukraine
Intercalated nanostructures of InSehtd and GaSehtd are fabricated.
Phenomena of the negative photocapacitance and the quantum capacitance
are visualized for the first nanostructure. The introduction of histidine
between indium selenide layers leads to increasing of conductivity anisot-
ropy (||/) from 67 to 226. Temperature dependences of a real component
of the complex impedance indicate semiconductor mechanism of conduc-
tivity along nanolayers with two activation energies of 1.6 meV in low-
temperature region and of 0.25 meV in high-temperature one. An appear-
ance of the giant high-frequency negative magnetoresistance and almost
20-fold photosensibility increasing are observed for the second nanostruc-
ture. The conductivity anisotropy (||/) of the nanostructure GaSehtd
is 102. Temperature dependence of a real component of the complex im-
pedance along the layers within the temperature regions 30Ct10C,
10Ct30C, 30Ct50C demonstrates cardinally different mecha-
nisms of conductivity. Activation energies are 0.35 in low-temperature
interval and 0.69 in high-temperature one. Non-activated conductivity
mechanism is observed in the range of temperature 10Ct30C. The
parameters of the energy spectrum calculated by means of the Geballe–
Pollak theory prior to and after the introduction of histidine into both
nanostructures are given. It well correlates with experimental data.
Сформовано інтеркалянтні наноструктури InSehtd> та GaSehtd. Для
першої наноструктури візуалізовано ефекти неґативної фотоємности та
квантової ємности. Втілення гістидину між шарами селеніду індію
приводить до зростання анізотропії електропровідности ||/ від 67 до
226. Температурні залежності реальної складової комплексного імпеда-
нсу засвідчують напівпровідниковий механізм провідности вздовж ша-
рів із двома енергіями активації — у 1,6 меВ у низькотемпературній та
у 0,25 меВ у високотемпературній областях. Для другої наноструктури
Наносистеми, наноматеріали, нанотехнології
Nanosystems, Nanomaterials, Nanotechnologies
2015, т. 13, № 3, сс. 403–414
2015 ІÌÔ (Іíñòèòóò ìåòàëîôіçèêè
іì. Ã. Â. Êóðäþìîâà ÍÀÍ Óêðàїíи)
Надруковано в Óкраїні.
Ôотокопіювання дозволено
тільки відповідно до ліцензії
404 F. O. IVASHCHYSHYN, I. I. GRYGORCHAK, and M. I. KLAPCHUK
спостерігаються 20-кратне зростання фоточутливости і поява гігантсь-
кого високочастотного неґативного магнетоопору. Анізотропія електро-
провідности ||/ наноструктури GaSehtd становить 102. Температур-
на залежність реальної складової комплексного імпедансу уздовж ша-
рів у областях температур 30Ct10C, 10Ct30C, 30Ct50C
демонструє кардинально відмінні механізми електропровідности. Енер-
гії активації становлять 0,35 у низькотемпературному та 0,69 у висо-
котемпературному інтервалах. При температурах 10Ct30C спосте-
рігається неактиваційний механізм електропровідности. Для двох на-
ноструктур наведено значення параметрів зонного спектру до і після
втілення гістидину, обчислені за теорією Джебола–Поллака, які добре
корелюють з одержаними експериментальними даними.
Сформированы интеркалянтные наноструктуры InSehtd и GaSehtd.
Для первой наноструктуры визуализированы эффекты отрицательной
фотоёмкости и квантовой ёмкости. Внедрение гистидина между слоями
селенида индия приводит к росту анизотропии электропроводности
||/ от 67 до 226. Температурные зависимости реальной составляющей
комплексного импеданса свидетельствуют о полупроводниковом меха-
низме проводимости вдоль слоёв с двумя энергиями активации — 1,6
мэВ в низкотемпературной и 0,25 мэВ в высокотемпературной обла-
стях. Для второй наноструктуры наблюдаются 20-кратный рост фото-
чувствительности и появление гигантского высокочастотного отрица-
тельного магнетосопротивления. Анизотропия электропроводности ||/
наноструктуры GaSe<htd> составляет 102. Температурная зависимость
реальной составляющей комплексного импеданса вдоль слоёв в темпе-
ратурных областях 30Ct10C, 10Ct30C, 30Ct50C де-
монстрирует кардинально отличающиеся механизмы электропроводно-
сти. Энергии активации составляют 0,35 в низкотемпературном и 0,69
в высокотемпературном интервалах. При температурах 10Ct30C
наблюдается неактивационный механизм электропроводности. Для
двух наноструктур приведены значения параметров зонного спектра до
и после внедрения гистидина, вычисленные по теории Джеболла–
Поллака, которые хорошо коррелируют с полученными эксперимен-
тальными данными.
Key words: InSe, GaSe, histidine, clathrates, supramolecular structure,
intercalation, impedance spectroscopy, Nyquist diagram, electrical con-
duction.
Ключові слова: Inse, GaSe, гістидин, клатрати, супрамолекулярна
структура, інтеркаляція, імпедансна спектроскопія, Найквістова діяг-
рама, електропровідність.
Ключевые слова: InSe, GaSe, гистидин, супрамолекулярная структура,
интеркалирование, импедансная спектроскопия, диаграмма Найквиста,
электропроводность.
(Received 28 May, 2015)
IMPEDANCE ANISOTROPY AND QUANTUM PHOTOCAPACITY OF CLATHRATES 405
1. INTRODUCTION
With rapid development of nanoengineering (nanoelectronics, quan-
tum coherent spintronics, etc.) and with related to these sciences
necessity to initiate creation of super-high-capacitance accumulators
of electric energy, the formation of heterostructured inorganic–
inorganic, inorganic–organic, and bio–organic materials attract still
more attention of scientists. The ability to realize unique physical
and chemical properties [1, 2], sometimes paradoxical, is associated
with these materials.
The known methods of obtaining them, such as vacuum deposi-
tion, photolithography, synthetic Langmuir–Blodgett techniques,
have some limitation caused by limited variability of the choice of
different heteroingridients and by problematic synthesis of ‘host–
guest’ configuration, especially synthesis of heteroaggregate ones.
By this time, only a small experience gained on this way and made
small steps [3, 4]. As far as bionanosemiconductor inorganic multi-
layered nanohybrids are concerned, nowadays, information on such
investigations is lacking at all. Therefore, the aim of this work is to
fill, to some extent, the gap in this branch of investigations.
2. RESULTS AND DISCUSSIONS
To form bio-inorganic/semiconductor nanohybrids, in which layered
crystals of gallium selenide (GaSe) and indium selenide (InSe) were
used as semiconductor matrix, and the aminoacid histidine
(C6H9N3O2) was chosen as a biologically active guest element the
suggested three-stage scheme of nanoengineering of crystals was
used in [5]. The main feature of histidine is that it is a zwitterion
(i.e., it possess properties of both anion and cation) with colossal di-
pole moment.
Formation of the histidine nanolayers in a threefold expanded
matrix of indium selenide leads to more than fortyfold increasing of
the real component of specific complex impedance and to almost
fourfold increasing of the photosensitivity in the direction perpen-
dicular to the plane of nanolayers.
At the same time, the effect of photoinduced ‘negative capaci-
tance’ is observed: the corresponding low-frequency impedance hod-
ograph branch enters the fourth, inductive quadrant of the complex
impedance plane that correlates with the low-frequency oscillation
ReZ() at illumination (see curve 6 on Fig. 1). In this case, the
mechanism of negative photocapacitance is most likely associated
with the photoexcitation of electrons from occupied states below the
Fermi level and, therefore, with the formation of trap centres for
injected electrons with the relaxation time greater than the half-
406 F. O. IVASHCHYSHYN, I. I. GRYGORCHAK, and M. I. KLAPCHUK
period sinusoidal signal.
According to this, the equivalent electric circuit can be repre-
sented as shown in Fig. 2. The first parallel high-frequency link
R1||CPE1 (where CPE1 is element of constant phase capacitive type
[6]) in the circuit models the distributed capacitance caused by the
presence of vacancies or impurity defects that provide electronic
conductivity at room temperature. Second R2||CPE2, the middle-
frequency link, displays the path current flow through energy bar-
riers in guest positions. The low-frequency link СQ||RrecL models the
path current flow through the boundary of separation of histidine–
semiconductor matrix. Here, Rrec is the resistance recombination,
which simulates a barrier to charge СQ, L is the inductance, СQ is
the quantum capacitance [7], which is described by the equation
CQe2dn/dEFn, where n is the concentration of electrons, EFn is the
energy of the electron Fermi quasi-level. For the last branch of the
low-frequency section, admittance can be written as follows:
rec
1
( )Y i C
R
, (1)
where ССLCQ,
2
rec/LC L R .
According to equation (1), impedance of last link in an equivalent
electric circuit for an illuminated nanohybrid at very low frequen-
cies ( rec1 ( )R C ) is a parallel connection of recombination re-
sistance and a constant negative capacitance C. Note that, at condi-
Fig. 1. Frequency dependences of complex impedance perpendicular to the
nanolayers of expanded matrix InSe (1–3) and of nanostructure InSe<htd>
(4–6), and along layers InSe<htd> (7–9) as measured in the dark (1, 4, 7)
or at illumination (3, 6, 9), and measured at the action of magnetic field
(2, 5, 8).
IMPEDANCE ANISOTROPY AND QUANTUM PHOTOCAPACITY OF CLATHRATES 407
tion СL CQ, low-frequency branch comes in IV-inductive quadrant,
showing inductive response. Table 1 shows the parameters of the
band spectrum prior to and after the introduction of histidine in
InSe, which are calculated with the Geballe–Pollak theory. It is evi-
dent that histidine encapsulation reduces the density of states at
the Fermi level an order of magnitude, which well correlates with
low-frequency areas of ReZ(), at the same time, significantly re-
ducing the distribution of trap centres. Radius of jump can be con-
sidered stable.
Study of the path current flow along the layers of expanded ma-
trix InSe and nanohybridized structure InSehtd in the frequency
range of 103–1 Hz showed that the conductivity anisotropy (||/)
with the introduction of histidine increases from 67 to 226.
The growth of ReZ() perpendicular to the nanolayers after the
introduction of histidine may be caused by decreasing of carrier
mobility due to ‘rotational’ polaron formation, and its falling along
them likely caused by the increasing carrier concentration due to
the modification of the band structure InSe by the electric field of
‘guest’ assuming ‘ferroelectric’ ordering of histidine dipoles along
layers as shown in Fig. 3, a.
As shown in our work [8] for the latter case along the q-axis of
the Brillouin zone, the valence band splits into two subbands; at the
same time, widths of subbands reduce comparatively to the unper-
turbed system.
A similar situation for the conduction band can be obtained. As a
result, one of the branches of the valence band arises along the en-
Fig. 2. The equivalent electric circuit.
TABLE 1. The parameters of the band spectrum prior to and after the in-
troduction of histidine into InSe.
Density
of jumping centres
near the Fermi level
N(F)1044, J1m1
Radius
of jump
R108, m
Distribution
of trap centres
near the Fermi level
J1023, J
Real density
of deep trap
centres
Nt1022, m3
InSe 32.13 2.90 0.61 1.96
InSehtd 2.32 2.39 15.07 3.50
408 F. O. IVASHCHYSHYN, I. I. GRYGORCHAK, and M. I. KLAPCHUK
ergy scale ‘up’ and one of the branches of the conduction band goes
‘down’ (Fig. 3, b). As a consequence, the effective bandgap decreas-
es or conduction band catch the Fermi level; this leads to increasing
of the concentration of carriers.
Photosensitivity along layers of InSehtd is almost twice less
than perpendicular to them, while for the expanded matrix, these
values are virtually identical. When they are illuminated, it is ob-
served anomalous frequency dependence ReZ(); it is the monotonic
growth with increasing frequency in fairly wide frequency range
(curve 9 in Fig. 1). In this case, low-frequency branch of the hodo-
graph of the impedance is almost parallel to ReZ-axis with opposite
its genesis as well as to the relevant branch of hodograph built to
measure in the dark. If the latter are modelled by finite element of
constant phase (BCPE) [6], which reflects the path current flow in
space-restricted area with the complex electrical conductivity, then
at illumination, one can proposed a model of impedance along the
layers containing the link with quantum capacity Lurie [7]. In this
case, it represents a contribution from the histidine nanoclusters
with the energy spectrum of the path current flow caused by the
nonequilibrium carriers. As a result, a conductivity of nonequilibri-
um carriers due to gravity in accordance with the [9] should de-
crease with increasing frequency, as observed in Fig. 1 (curve 3).
Temperature dependences of the real component of the complex
impedance along the layers (Fig. 4) indicate semiconductor nature
of the electrical conductivity of nanohybrids with two activation
energies: 1.6 meV in low-temperature region and 0.25 meV in high-
temperature one. It is interesting to note that for proper tempera-
ture of change of conductivity mechanism at (10C) corresponds to
a radical change of the low-frequency branch of Nyquist diagrams:
the passing to the fourth, inductive, quadrant (inset to Fig. 4). This
makes it possible to assume that, at temperatures higher than
10C, electrons captured by trap centres would be delocalized.
With reducing the temperature to 30C, localized electrons no
a b
Fig. 3. Ferroelectric arrangement of dipoles (a) and the schematic presen-
tation of band structure modification of InSehtd layers (b).
IMPEDANCE ANISOTROPY AND QUANTUM PHOTOCAPACITY OF CLATHRATES 409
longer is delocalized in the tails of the density of states.
For the initial expanded matrix (curve 1 in Fig. 5), we have usual
situation: the corresponding hodograph of impedance is of two-arc
form, and it represents capacitive response of localized states and
the frequency depended impedance proper caused by jumps between
localized states near the Fermi level in the packet of atomic mono-
Fig. 4. Temperature dependences of a real component of impedance along
nanolayers InSehtd. In the inset to Fig. 4, hodograph of impedance is
given.
Fig. 5. Nyquist diagram measured in the dark for the initial expanded ma-
trix GaSe (1) and for the nanostructure GaSe<htd> (2) (with equivalent
electric circuits corresponding to them).
410 F. O. IVASHCHYSHYN, I. I. GRYGORCHAK, and M. I. KLAPCHUK
layers (high-frequency curve). The middle-frequency curve repre-
sents the path current flow through widened spaces of actions of
the van der Waals forces. These arcs are modelled by means of
bounded element of constant phase (BCPE), which represents the
path of current flow in space-restricted domain of complex-valued
electric conductance [10]. The low-frequency section represents the
distribution of active resistance element (caused by discretization of
the energy spectrum of the expanded matrix of gallium selenide),
this resistance is modelled by means of constant phase element CPE
with low value of phase deviation 0.1 [6].
The equivalent electric circuit in this case is given in the inset (a)
to Fig. 5. The introduction of histidine leads to the increase in fre-
quency dispersion of the hodograph of the impedance, and it indi-
cates the emergence of additional potential barriers. Accordingly,
the equivalent electric circuit is as shown in inset (b) in Fig. 5. The
last link contains induction (inset (b) in Fig. 5) because the low-
Fig. 6. Frequency dependences of a real component of impedance perpen-
dicular to the layers for initial expanded matrix GaSe measured in the
dark (1) and for nanostructure GaSehtd measured in the dark (2) as well
as at illumination (4), and measured at the action of magnetic field (3).
TABLE 2. The parameters of the energy spectrum prior to and after the
introduction of histidine in GaSe.
Density
of jumping centres
near the Fermi level
N(F)1043, J1m1
Radius
of jump
R108, m
Distribution
of trap centres
near the Fermi level
J1022, J
Real density
of deep trap
centres
Nt1022, m3
GaSe 6.56 3.02 2.63 1.73
GaSe<htd> 10.60 2.83 1.99 2.10
IMPEDANCE ANISOTROPY AND QUANTUM PHOTOCAPACITY OF CLATHRATES 411
frequency branch of the Nyquist diagram passes to the induction
quadrant IV of the plane of complex-valued impedance. This indi-
cates the phenomenon of ‘negative capacitance’.
The introduction of histidine between selenide layers leads to
twenty-fold growth of the real component of complex impedance in
the low-frequency spectrum (103–1 Hz) (Fig. 6). Lighting of the
nanostructures GaSehtd causes a decrease of ReZ() almost by
5103 times in the specified frequency range (curve 4 in Fig. 6). The
latter phenomenon is quite expected, as semiconductor matrix is
photosensitive in the visible spectrum. However, compared to the
enhanced matrix implementation htd leads to an almost 20-fold
increasing of photosensitivity. At the same time, Figure 6 (curve 4)
shows the previously non-observed effect of the giant high-
frequency negative magnetoresistance: in the frequency range
60 106 Hz, magnetic field strength of 2.75 kОе at room tem-
perature leads to a more than 5-fold reduction of ReZ(). Taking
into account no practical visualization of the magnetoresistance at
lower frequencies, this effect can most likely be associated with
Zeeman delocalization of charge carriers from the deeper trap cen-
tres. Table 2 shows the parameters of the energy spectrum before
and after the introduction of histidine in GaSe as calculated within
the Geballe–Pollak theory. In contrast to InSe, one can see a de-
crease of density of jumping centres and distribution of trap levels
near the Fermi level.
Behaviour of hodograph of impedance along the impedance layers
GaSehtd has the same character as in the measurement perpen-
dicular, with the exception of the magnetic field. In this case, the
frequency dispersion growth and middle/high-frequency branches of
Fig. 7. Nyquist diagram GaSehtd perpendicular to the layers and along
them (see inset).
412 F. O. IVASHCHYSHYN, I. I. GRYGORCHAK, and M. I. KLAPCHUK
Nyquist diagrams ‘pass’ in inductive quadrant of the plane of com-
plex-valued impedance (see the inset in Fig. 7). This is to some ex-
tent correlated with the above discussed Zeeman localization (delo-
calization) of charge carriers.
Investigation of the path current flow along the layers of nano-
hybridized structure GaSehtd showed that, in the frequency
range (1031 Hz), electrical conductivity anisotropy is ||/102,
and reduction of the real component of the complex impedance at
illumination reaches tenfold value. In contrast to the previous
measurement geometry, in this case, positive magnetoresistance is
visualized at lower frequencies from 102 Hz: ReZ() in a magnetic
field is growing more than twice. In this case, high-frequency nega-
tive magnetoresistance not only preserved in the same frequency
range, but its increasing reaches almost 14-fold value. Obviously,
this is an indication of different energy structure in perpendicular
and along the layers direction.
The temperature dependence for GaSehtd along the layers
demonstrates cardinally different mechanisms of conductivity at
temperature regions 30Ct10C, 10Ct30C, 30Ct50C
(Fig. 8). If the first and last temperature ranges correspond to the
activation mechanism, then one can obtains non-activation mecha-
nism of conductivity in the range of temperatures 10Ct30C.
3. CONCLUSIONS
The introduction of histidine into three-fold expanded matrix of
indium selenide leads to forty-fold increasing of a real component
Fig. 8. Temperature dependences of a real component of impedance along
nanolayers GaSehtd. In the inset, their frequency dependences are given.
IMPEDANCE ANISOTROPY AND QUANTUM PHOTOCAPACITY OF CLATHRATES 413
of specific complex impedance and almost four-fold increasing of
photosensibility in direction perpendicular to nanolayers.
An appearance of photoinductive ‘negative photocapacitance’ is
observed for nanostructure InSehtd; the mechanism of this phe-
nomenon is most likely associated with the photoexcitation of elec-
trons from occupied states below the Fermi level and, therefore,
with the formation of trap centres for injected electrons with the
relaxation time greater than the half-period sinusoidal signal.
The conductivity anisotropy (||/) due to the introduction of
histidine into extended matrix of InSehtd increases from 67 to
226 in the frequency range of 103–1 Hz.
Temperature dependence of a conductivity of the InSehtd
nanostructure has a semiconductor character with two activation
energies of 1.6 meV and 0.25 meV.
The introduction of histidine into three-fold expanded matrix of
gallium selenide leads to twenty-fold increasing of a real component
of specific complex impedance and twenty-fold increasing of photo-
sensibility in direction perpendicular to nanolayers.
The evidence of a giant high-frequency negative magnetore-
sistance is observed for nanostructure GaSehtd in constant mag-
netic field with strength of 2.75 kOe at room temperature; magnet-
ic field leads to a more than 5-fold reduction of ReZ() in the fre-
quency range 60 106 Hz.
The conductivity anisotropy (||/) for the GaSehtd nanostruc-
ture is 102, and decrease of a real component of the complex imped-
ance at illumination reaches ten-fold value. At the same time, posi-
tive magnetoresistance is visualized at frequencies less than 102
Hz: there is ReZ() growth by more than twice in magnetic field,
and high-frequency negative magnetoresistance growth is reaching
almost 14-fold value.
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