Chlorpyrifos is one of the most widely used pesticides that acts on nervous system by inhibiting acetylcholinesterase. Prolonged use chlorpyrifos causes severe neurological, autoimmune, and persistent developmental disorders in humans. Therefore, this study, a highly sensitive robust biosensor platform was devised fabricating graphene field effect transistors (graFET) Si/SiO2 substrate for detection real samples. Anti-chlorpyrifos antibodies were immobilized successfully surface. Under...

Graphene, a two-dimensional nanomaterial, has gained immense interest in biosensing applications due to its large surface-to-volume ratio, and excellent electrical properties. Herein, compact user-friendly graphene field effect transistor (GraFET) based ultrasensitive biosensor been developed for detecting Japanese Encephalitis Virus (JEV) Avian Influenza (AIV). The novel sensing platform comprised of carboxy functionalized on Si/SiO

The myriad technological applications of infrared radiation sensors make the search for ultra-sensitive detectors extremely crucial.

We report charge to spin conversion in a hybrid heterostructure comprised of atomically thin bismuth (Bi) confined between silicon carbide (SiC) substrate and epitaxial graphene (EG). confirm composition, dimensionality, 96.5 \% intercalation coverage using X-ray photolectron spectroscopy, scanning transmission microscopy, low energy electron diffraction, Raman spectroscopy. Electrical transport measurements show signs weak antilocalization the heterostructure, consistent with spin-orbit...

Engineering the properties of layered metal dichalcogenides (LMDs) requires stringent control their morphology. Herein, using a scalable one-step solvothermal technique, we report synthesis SnSe2 under two different conditions, leading to formation nanoflakes and nanoflowers. The use oleic acid in reaction leads nanoflowers, presence ethanol medium nanoflakes. Ab initio density functional theory calculations rationalise this observation, revealing stronger adsorption on {0001} facet compared...

Slow intrinsic fluctuations of resistance, also known as the flicker noise or 1/f-noise, in surface transport strong topological insulators (TIs) is a poorly understood phenomenon. Here, we have systematically explored 1/f-noise field-effect transistors (FET) mechanically exfoliated Bi1.6Sb0.4Te2Se TI films when occurs predominantly via states. We find that slow kinetics charge disorder within bulk induces mobility at surface, providing new source unique to systems. At small channel...

The weak interlayer coupling in van der Waals solids allows isolation of individual atomic or molecular layers with remarkable electrical, optical, and structural properties. applicability these two dimensional materials future electronic architectures requires a thorough understanding the electrical transport mechanisms as well factors limiting device performance. study slow time-varying fluctuations resistance, often called 1 / f noise, offers deep insight into scattering mechanisms, also...

Implementing topological insulators as elementary units in quantum technologies requires a comprehensive understanding of the dephasing mechanisms governing surface carriers these materials, which impose practical limit to applicability materials such requiring phase coherent transport. To investigate this, we have performed magnetoresistance (MR) and conductance fluctuations (CF) measurements both exfoliated molecular beam epitaxy grown samples. The breaking length...

The great practical utility has motivated extensive efforts to discover ultra-low resistance electrical conductors and superconductors in ambience. Here we report the observation of vanishingly small at ambient temperature pressure conditions films pellets a nanostructured material that is composed silver particles embedded into gold matrix. Upon cooling below sample-specific scale ($T_{C}$) as high $286$ K, film drops $\sim 2μΩ$, being limited by measurement uncertainty. corresponding...

We report the molecular beam epitaxy of Bi1−xSbx thin films (0 ≤ x 1) on sapphire (0001) substrates using a (Bi,Sb)2Te3 buffer layer. The characterization reflection high energy diffraction, x-ray atomic force microscopy, and scanning transmission electron microscopy reveals epitaxial growth reasonable structural quality. This is further confirmed via diffraction pole figures that determine registry between film substrate. investigate microscopic structure Raman spectroscopy, demonstrating...

We report detailed temperature and gate-voltage dependence of 1/f resistance noise in magnetically doped topological insulators (TI) Crx(Bi,Sb)2−xTe3. The is remarkably sensitive to the gate voltage, increasing rapidly as chemical potential moved towards charge neutrality point. Unlike identically prepared (Bi,Sb)2Te3 films, where mobility-fluctuations surface states dominant mechanism, magnetic Crx(Bi,Sb)2−xTe3 originates from transport localized band tail bulk valence band. A strong...

Abstract Au–Ag nanostructures comprising of ∼1 nm Ag nanoparticles embedded into an Au matrix show several unconventional optical, electric and magnetic properties. Here, we review progress made towards the preparation these materials as well analysis their structure. Further, electrical transitions in are discussed. Finally, properties revealed from optical electron microscopic probes.

Abstract The diverse properties of two-dimensional materials have been utilized in a variety architecture to fabricate high quality electronic circuit elements. Here we demonstrate generic method control hysteresis and stable memory effect Van der Waals hybrids with floating gate as the base layer. can be charged global back gate-voltage, which it retain manner. Such devices provide very high, leakage-free effective gate-voltage on field-effect transistors due capacitance amplification, also...

We report the synthesis and characterization of thin films Weyl semimetal NbAs grown on GaAs (100) As-terminated (111)B substrates. By choosing appropriate substrate, we can stabilize growth in [001] [100] directions. combine x-ray with high-angle annular dark field scanning transmission electron microscopy to understand both macroscopic microscopic structure films. show that these are textured domains tens nanometers size that, a scale, mostly aligned single crystalline direction. describe...

A key feature of topological insulators (TIs) is symplectic symmetry the Hamiltonian which changes to unitary when time-reversal lifted and a phase transition occurs. However, such crossover has yet be explicitly observed by directly probing class Hamiltonian. In this Rapid Communication, we have probed measuring mesoscopic conductance fluctuations in TI ${\mathrm{Bi}}_{1.6}{\mathrm{Sb}}_{0.4}{\mathrm{Te}}_{2}\mathrm{Se}$, shows an exact factor 2 reduction on application magnetic field due...

We report a detailed study on low-frequency 1/f-noise in large-area molecular-beam epitaxy grown thin (∼10 nm) films of topological insulators as function temperature, gate voltage, and magnetic field. When the Fermi energy is within bulk valence band, temperature dependence reveals clear signature generation-recombination noise defect states band gap. However, when tuned to gap, voltage shows that resistance fluctuations surface transport are caused by correlated mobility-number density due...

The controlled modification of graphene's electronic band structure poses serious challenges. In the present work, we study effect sp 2 cluster size variation on gap and photoconductive properties reduced graphene oxide (RGO). This is achieved by performing reversible functionalization RGO with oxygen species. results in its partial transformation to (GO) so that clusters within 3 matrix varies, thereby affecting π-π* properties. reveals: (1) incremental creation/elimination oxygenated...

Doping of organic semiconductors enhances the performance optoelectronic devices. Although p-type doping is well studied and successfully deployed in devices, air stable n-type was still elusive. We succeeded with using molecular dopant N-DMBI under ambient conditions. Strikingly, accounts for a gigantic increase photoconductivity doped thin films. Electrical optical properties n-doped semiconductor were investigated by temperature dependent conductivity, electron paramagnetic resonance...

Transitions to immeasurably small electrical resistance in thin films of Ag/Au nanostructure-based have generated significant interest because such transitions can occur even at ambient temperature and pressure. While the zero-bias magnetic transition these been reported recently, non-equilibrium current-voltage ($I-V$) transport characteristics remains unexplored. Here we report $I-V$ zero field a prototypical nanocluster film close its resistivity critical $T_{C}$ $\approx160$ K. The...

Time-reversal invariance (TRS) and inversion symmetry (IS) are responsible for the topological band structure in Dirac semimetals (DSMs). These symmetries can be broken by applying an external magnetic or electric field, resulting fundamental changes to ground state Hamiltonian a phase transition. We probe these using universal conductance fluctuations (UCF) prototypical DSM, Cd3As2. With increasing magnitude of UCF decreases factor 2, agreement with numerical calculations effect TRS. In...

Graphene constitutes one of the key elements in many functional van der Waals heterostructures. However, it has negligible optical visibility due to its monolayer nature. Here we study graphene various heterostructures and include effects source spectrum, oblique incidence spectral sensitivity detector obtain a realistic model. A experiment is performed at different wavelengths, resulting very good agreement with our calculations. This allows us reliably predict conditions for better The...

The resistive transition in nanocomposite films of silver (Ag) nanoclusters ~ 1 nm diameter embedded gold (Au) matrix exhibits an anomalous resistance peak at the onset transition, even for temperatures as high 260 K. maximum value ranges between 30% - 300% above that normal state depending on devices well lead configuration within a single device. excess regime was observed about 10% devices, and extends from 10 100 Application magnetic field 9 T found to partially suppress resistance. From...

We report the observation of linear magneto-resistance (LMR) with a very low cross-over magnetic field (Bc) at room temperature in bismuth(110) thin films fabricated using thermal evaporation. The different temperatures (T) indicate that Bc has strong T-dependence, and displays remarkably small magnitude 180 mT T = 300 K. parameter Φ, defined as MR% (B 1 T)/ is 248, considerably higher compared to values previously reported literature. observed LMR likely due recombination carriers...