In this work, we have reported the temperature-dependent resistive switching (RS) behavior observed in (1-x)CuI.(x)La
0.7
Sr
0.3
MnO
3
nanocomposites with 0.001 <
x
< 0.05 within the ...temperature range of 150 K to 300 K. Here, we observed bipolar and interface-type RS behavior, where the resistance can be altered to its previous state by the application of an opposite bias voltage. The extensive analysis of the current versus voltage data for different compositions at room temperature revealed that the dominating transport mechanisms in the low and high bias regions, respectively, were Schottky emission and Poole–Frenkel effect. The enhanced switching response of the RS medium after the addition of La
0.7
Sr
0.3
MnO
3
can be attributed to the oxygen vacancy-induced conduction which was confirmed by X Ray Photoelectron Spectroscopy (XPS) measurements. In the endurance test, the highest ON/OFF ratio averaged over 100 cycles was observed to be 4.2 ± 1.1 and 3.8 ± 0.3 for
x
= 0.001 and 0.02 respectively at
T
= 300K. At
T
= 250 K, we obtained the optimal ON/OFF ratio of 19.8
±
1.8 for
x
= 0.001 and 22.7
±
4.1 for
x
= 0.02. The investigation of current versus voltage graphs for
T
= 250 K, 200 K, and 150 K further confirmed Schottky emission and the Poole–Frenkel effect as the dominating transport mechanisms at lower temperatures.
Phosphorene is a unique semiconducting two-dimensional platform for enabling spintronic devices integrated with phosphorene nanoelectronics. Here, we have designed an all phosphorene lattice lateral ...spin valve device, conceived via patterned magnetic substituted atoms of 3d-block elements at both ends of a phosphorene nanoribbon acting as ferromagnetic electrodes in the spin valve. Through First-principles based calculations, we have extensively studied the spin-dependent transport characteristics of the new spin valve structures. Systematic exploration of the magnetoresistance (MR) of the spin valve for various substitutional atoms and bias voltage resulted in a phase diagram offering a colossal MR for V and Cr-substitutional atoms. Such MR can be directly attributed to their specific electronic structure, which can be further tuned by a gate voltage, for electric field controlled spin valves. The spin-dependent transport characteristics here reveal new features such as negative conductance oscillation and switching of the sign of MR due to change in the majority spin carrier type. Our study creates possibilities for the design of nanometric spin valves, which could enable integration of memory and logic elements for all phosphorene 2D processors.
•The LCMO-rGO nancomposites have been synthesized using solid state method.•The resistive switching effect is observed to be most prominent at 200 K.•The operating voltage is observed to be decrease ...with increasing temperature.•The current study helps to understand the thermal effect of RS device.•The charge transport mechanism is well explained using SCLC and P-F emission.
In this work, we report the temperature-dependent transport and resistive switching behaviour of a promising hybrid structure made of La0.7Ca0.3MnO3 (LCMO) and reduced graphene oxide (rGO). The current-voltage (IV) characteristics are non-linear across the studied temperature range of 100 K–300 K, which is also temperature-dependent. The memristive effect is most prominent at 200 K, while the reduction of hysteresis in the IV-curve with decrease in temperature is ascribed to the low thermal energy of the charge carriers. The charge transport in the SET and RESET process at different temperatures can be explained using trap-controlled space charge limited conduction mechanism for temperature >200 K and Poole-Frenkel emission at temperatures below that.
Phosphorene has a unique set of characteristics such as a semiconducting nature, good carrier mobility and low-spin orbit coupling aspects which makes it a highly prospective two dimensional material ...for cross-hybrid architectures in nanoelectronics, spintronics, and optoelectronics. In the spintronic context, the creation of a stable magnetic order in phosphorene can be immensely beneficial for designing phosphorene spin circuits. In this work, we present high efficiency spin filtering behaviour in magnetically rendered phosphorene. First, we calculate the effect of doping various 3d block elements in phosphorene to introduce a stable magnetic order. Next, by varying doping concentrations in distinct doping configurations, an extensive phase diagram has been obtained depicting the presence of various electronic and magnetic states. This allows us to achieve a high magnetisation in the presence of various transition metal atoms, with a spin polarisation of ∼100% in half-metallic regimes. The transport behaviour reveals a map of the spin injection efficiency showing enhancement with doping concentration and reaching a perfect spin filtering capacity of ∼100% in the presence of Ti, Cr, Mn, Co, and Fe atoms. The present results offer new insights into engineered designs of multi-functional phosphorene spintronic circuits.
We present high efficiency spin filtering behaviour in magnetically rendered phosphorene, doped with various 3d block elements. A phase diagram was obtained depicting the presence of various electronic and magnetic states.
In this manuscript, we propose nickel antimony oxide (NiSb2O6, NSO), crystallized in the tri-rutile form, as a high capacity conversion-type anode material for the sodium-ion batteries. The material ...is synthesized via co-precipitation method followed by calcination at high temperatures. X-ray diffraction studies confirm the formation of a phase pure tri-rutile NSO powder after calcination at 1000 °C for 5 h. The as-prepared powder is then electrophoretically deposited on a copper foil along with carbon black as conductive additive to develop uniform, porous, and adherent NSO‑carbon black films. The deposited film is then tested as an anode for sodium-ion battery, which delivers a specific capacity of 255mAhg−1 after 50 cycles at a specific current of 100mAg−1, with a coulombic efficiency of ~98%. The deposited film also exhibits good cycling stability as well as rate capability. Furthermore, the film delivers a specific capacity of 140mAhg−1 after 100 cycles, when cycled at a higher specific current (750mAg−1).
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•NiSb2O6, a new Na-ion battery anode material is developed.•Electrophoretic deposition method is used to fabricate NiSb2O6‑carbon black anode.•EPD grown electrodes exhibit good electrochemical properties.
Burg’s entropy plays an important role in this age of information euphoria, particularly in understanding the emergent behavior of a complex system such as statistical mechanics. For discrete or ...continuous variable, maximization of Burg’s Entropy subject to its only natural and mean constraint always provide us a positive density function though the Entropy is always negative. On the other hand, Burg’s modified entropy is a better measure than the standard Burg’s entropy measure since this is always positive and there is no computational problem for small probabilistic values. Moreover, the maximum value of Burg’s modified entropy increases with the number of possible outcomes. In this paper, a premium has been put on the fact that if Burg’s modified entropy is used instead of conventional Burg’s entropy in a maximum entropy probability density (MEPD) function, the result yields a better approximation of the probability distribution. An important lemma in basic algebra and a suitable example with tables and graphs in statistical mechanics have been given to illustrate the whole idea appropriately.
•No long range ferromagnetism in transition metal doped ZnO.•The formation of bound magnetic polaron induces antiferromagnetism due to superexchange.•Long range ferromagnetism in the transition metal ...doped ZnO is still an open question.
In this report, we present a systematic study of magnetic behavior of transition metal (TM = Fe or Cu) doped ZnO and co-doped (Cu, Fe) ZnO nanoparticles. All the samples show antiferromagnetic (AFM) like inverse susceptibility at low temperatures. In all the samples AFM Curie-Weiss temperature TAFM increases with increase in TM ion concentration indicating enhanced antiferromagnetic correlation upon TM doping. We observe a crossover from antiferromagnetic correlation state to ferromagnetic correlation around temperature (T) 100–150 K. We shall try to explain all the experimental observations by invoking the role of oxygen vacancies, valency of transition metal ions, formation and interaction between bound magnetic polaron (BMP) and their melting in ZnO matrix. Even though we observe ferromagnetic correlation around room temperature in all these samples from the inverse magnetic susceptibility data, but no true long range ferromagnetic transition was observed in magnetization down to lowest measured temperature of 5 K. Our study indicates the difficulties in achieving long range ferromagnetism arising due to the formation of BMPs upon lowering the temperature where these BMPs get antiferromagnetically correlated due to superexchange interaction occurring in transition metal doped wide band gap semiconducting ZnO matrix.
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