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At least 73 records · Page 4
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DOE OSTI2018

Magnetic and Transport Properties of Co{sub 1+δ}Sb Single Crystals

For some 3d transition-metal monopnictides, their physical properties are strongly affected by interstitial 3d transition-metal atoms, such as Fe{sub 1+δ}Sb, in which the electrical transport, magnetic properties and carrier concentrations have strong dependence on the composition of interstitial Fe (Shiomi et al. Phys. Rev. Lett. 108(5), 056601 2012), Therefore, it is important to study the influence of interstitial Co on the physical properties of Co{sub 1+δ}Sb. Here, the magnetic and transport properties have been studied on Co{sub 1.05}Sb single crystals. The magnetic and electrical transport measurements reveal that stoichiometric CoSb is a nonmagnetic metal. The interstitial Co in this compound exhibits a paramagnetic behaviour and weak antiferromagetic correlations. However, it has no effect on transport properties. A very low magnetoresistance (≤ 0.2%) was observed under the magnetic field up to 14 T, which suggests that Co{sub 1+δ}Sb could be a potential material of electronic devices for the application at a high magnetic field.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Local Noncentrosymmetric Structure of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+y} by X-ray Magnetic Circular Dichroism at Cu K-Edge XANES

The two-dimensional Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+y} (Bi2212), the most studied prototype cuprate superconductor, is a lamellar system made of a stack of two-dimensional corrugated CuO{sub 2} bilayers separated by Bi{sub 2}O{sub 2+y}Sr{sub 2} O{sub 2} layers. While the large majority of theories, proposed to interpret unconventional high T{sub c} superconductivity in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+y}, assume a centrosymmetric tetragonal CuO{sub 2} lattice for the [CuO{sub 2}]Ca[CuO{sub 2}] bilayer, here, we report new compelling results providing evidence for local noncentrosymmetric symmetry at the Cu atom. We have measured polarized Cu K-edge XANES (X-ray absorption near-edge structure) and the K-edge X-ray magnetic circular dichroism (XMCD) of a Bi2212 single-crystal near-optimum doping. The Cu K-edge XMCD signal was measured at ID12 beamline of ESRF with the k-vector of X-ray beam parallel to c-axis, i.e., with the electric field of X-ray beam E//ab, using a 17-T magnetic field parallel to the c-axis of a Bi2212 single crystal. Numerical simulations of the XMCD signal of Bi2212 by multiple scattering theory have shown agreement with the experimental XMCD signal only for the local structure with noncentrosymmetric Bb2b space group of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+y}.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Ab Initio Study of Structural, Electronic, and Magnetic Properties of A{sub 1−x}{sup III}Mn{sub x}B{sup VI}: In{sub 1−x}Mn{sub x}S-Diluted Magnetic Semiconductor

First-principles density functional calculations on the new class of diluted magnetic semiconductor A{sub 1−x}{sup III}Mn{sub x}B{sup VI} In{sub 1−x}Mn{sub x}S for x = 0.25 and 0.5 are investigated to study the structural, electronic, and magnetic properties, employing the full-potential linearized augmented plane wave method. Electronic band structures and density of states revealed a half-metallic character of In{sub 1−x}Mn{sub x}S and show the stability of anti-ferromagnetic states as compared with ferromagnetic states. The calculated exchange constants J{sub dd} are in good agreement with experimental and theoretical results on magnetic properties of single crystalline A{sub 1−x}{sup III}Mn{sub x}B{sup VI} in the anti-ferromagnetic case. Our predicated calculations on the s,p-d exchange constants N{sub 0}α and N{sub 0}β show that they are lower than in A{sub 1−x}{sup II}Mn{sub x}B{sup VI} DMS. The local environment is found tetrahedral as in the II–VI DMS and other (III,Mn) VI compounds. The total magnetic moment for In{sub 1−x}Mn{sub x}S for different concentrations is in accordance with the exact value 5 μ{sub B} and comes mainly from impurity Mn. The local magnetic moments of Mn ions are reduced from their free space charges values due to the p-d hybridization which produces small magnetic moments on the nonmagnetic In and S sites. The Curie temperature of In{sub 1−x}Mn{sub x}S is calculated within the mean field approximation and compared with other DMS systems.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Abnormal Transport and Magnetic Properties Induced by Change of the Phase Volume Ratio for YBa{sub 2}Cu{sub 3}O{sub 7-δ}/La{sub 0.67}Sr{sub 0.33}MnO{sub 3} Hybrids

Two elaborately designed hybrids consisting of superconducting YBa{sub 2}Cu{sub 3}O{sub 7-δ} (YBCO) and ferromagnetic La{sub 0.67}Sr{sub 0.33}MnO{sub 3} (LSMO), namely 20 × (YBCO(m)/LSMO(100 − m)) are prepared on single crystal SrTiO{sub 3} (STO) by pulsed laser deposition (PLD) with 20 being repetition periods and m = 90 and 10, respectively, which represents YBCO pulse number in a period. The films show highly c-oriented and epitaxial quality, suggested by XRD 𝜃–2𝜃 scans and pole figures. The 20 × (YBCO90/LSMO10) sample with a large YBCO volume fraction exhibits the typical character of a metal superconductor at about 90 K, while its transition width reaches 9.1 K, which is nearly eight times of that of the pure YBCO film. Above the superconducting transition temperature, a superparamagnetic signal rather than ferromagnetic behavior is observed, which may be associated with a diluted system consisting of the ferromagnetic nanoparticles embedded in the superconducting films. For the hybrid with a small YBCO volume fraction, i.e., the 20 × (YBCO10/LSMO90) sample, its transport behavior at normal state is insulating, and it is found that the Mott variable range hopping conduction dominates in this insulating phase in the temperature range 70–310 K. Obviously distinguishable insulator to superconductor (IS) transition occurs at 52 K, but the superconducting diamagnetic signals are very weak in the magnetic measurements below the IS temperature. For this sample, the magnetization loop at 100 K is ferromagnetic, yet manifested by a reduced coercive field and residual magnetization as compared with a pure LSMO film. In fact, both hybrids represent two kinds of nanocomposites, i.e., superconducting nanoparticles in a ferromagnetic matrix and ferromagnetic nanoparticles in a superconducting matrix, which benefits to study interfacial interactions due to an increased interface to value ratio and reduced size effect.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Pinning-Induced Vortex-System Disordering at the Origin of the Second Magnetization Peak in Superconducting Single Crystals

The nature of the second magnetization peak (SMP) appearing on the dc magnetic hysteresis curves of superconducting single crystals with random pinning is still under debate. Many interesting SMP models and mechanisms were proposed and considered so far, and it is believed at present that this effect is system dependent. We analyzed the dc magnetization curves and the magnetic relaxation in the SMP domain for various single-crystal specimens (superconducting cuprates and iron-based superconductors), of different pinning strengths, with the external magnetic field H oriented along the crystallographic c axis or perpendicular to it. The sample independent aspects revealed by the relaxation results are the absence of single-vortex collective pinning around the SMP onset field and the sign changing of the vortex creep exponent between the onset field and the peak field. This general behavior supports strongly the pinning-induced disordering of the low-H quasi-ordered vortex solid as the actual scenario for the SMP.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Tunable Optical Behaviour and Room Temperature Ferromagnetism of Cobalt-Doped BaSnO{sub 3} Nanostructures

In this work, the effect of Co doping on the structural, vibrational, morphological, optical and magnetic behaviour of BaSnO{sub 3} nanostructures is reported. Pure and Co (1,3, and 5%)-doped barium stannate (BSO) nanostructures were prepared by conventional hydrothermal technique followed by calcination at 900 °C for 5 h. The single crystalline cubic phase was identified by XRD analysis and structural distortions associated with Co doping were evidenced by variation in microstarin and crystallite size. FTIR and Raman studies further confirm the structural quality of the prepared samples. FESEM analysis revealed the mixed morphology of prepared samples, and the chemical compositions of all the samples were analysed using EDAX studies. The absorption studies revealed the incorporation of dopant ions and their effect on the bandgap subsequently in samples. The presence of defects and paramagnetic centres in the samples were confirmed by PL and EPR analyses. Magnetization studies demonstrated that pure BSO exhibits characteristic diamagnetism at room temperature and the addition of Co into Ba–Sn–O lattice drives the F-centre exchange interactions which results in the ferromagnetic behaviour. Hence, the occurrence of diamagnetic to ferromagnetic transition at room temperature with addition of Co as a dopant was identified.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

In-field Conductivity Fluctuations in Ba{sub 0.72}K{sub 0.28}Fe{sub 2}As{sub 2} Single Crystals

Fluctuations in the conductivity of Ba{sub 0.72}K{sub 0.28}Fe{sub 2}As{sub 2} single crystal are studied systematically by resistance measurements as a function of temperature and magnetic field. A clear Maki−Thompson and Aslamakov−Larkin (MT–AL) two- to three-dimensional (2D–3D) crossover is found on the excess conductivity (Δσ) curves as the temperature approaches the superconducting critical temperature, T{sub c}. 3D fluctuations in superconductivity are realized near T{sub c} that are well fitted to experimental data by the 3D Aslamazov–Larkin theory. The Maki–Thompson model shows a 2D conductivity fluctuation above the 2D-3D temperature transition, T{sub 0}, which depends on magnetic field. Results show that the 2D-3D dimensional crossover moves to lower temperature with increasing magnetic field. The values of the transition temperature and the crossover in the reduced temperature, ln(ε{sub 0}), as functions of magnetic field were used to determine the coherence length and the lifetime, τ{sub φ}, of the fluctuational pairs at the temperature of 35 K. Analysis of the Ba{sub 0.72}K{sub 0.28}Fe{sub 2}As{sub 2} single crystal gives a value of 3.76 × 10{sup − 12} s for the τ{sub φ} in the absence of magnetic field and it decreases to 2.4 × 10{sup − 12} s in magnetic field of 13 T.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

On the Origin of Enhanced Critical Current Density and Thermal-Activated Flux Flow in K{sub x}Fe{sub 2−y}Se{sub 2} Superconductors: the Effect of Quenching and Mn Doping

A magnetotransport, vortex pinning, and critical current density study of superconducting K{sub 0.8}Fe{sub 2−z}Mn{sub z}Se{sub 2} (z = 0, 0.02) single crystals is reported. The parameters of upper critical field, coherence length, and anisotropic ratio at 0 K are presented. Based on thermally activated flux flow model, the values of pinning potential, U{sub 0}{sup ∥{sub c}}(U{sub 0}{sup ∥{sub a}{sub b}}), at 0.25 T are derived to be as large as 1.3 × 10{sup 4}(1.8 × 10{sup 4}) K for z = 0.02, which shows rather robust and retains still larger than pure ones up to 9 T. Utilizing scanning electron microscope, it is revealed the increased magnitude of magnetic moment in magnetic hysteresis loops correlates well with the crystal morphology variation. The evidence on the inhomogeneous distribution of Mn dopants between the matrix and stripe phase is also shown. Furthermore, the temperature dependence of critical current density is analyzed by different pinning regimes and the model of granular superconductor. It is demonstrated that the Josephson coupling between superconducting grains exists in quenched K{sub 0.8}Fe{sub 2−y}Se{sub 2}. However, for Mn-doped sample, the Mn dopant can induce strong vortex pinning in the form of fine K–Mn–Se inclusions.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Influence of Oxygen on the Tribomechanical Properties of Single Crystals of YBa{sub 2}Cu{sub 3}O{sub 7−δ}

This paper reports a study on the mechanical and tribological properties of ab- and a (b) c−planes of YBa{sub 2}Cu{sub 3}O{sub 7−δ} single crystals. The single crystals were grown using a CuO-BaO self-flux method. The oxygenation effect on the mechanical and tribological properties of ab- and a (b) c−planes is reported. For the ab- plane, the hardness and elastic modulus were around 6 and 50 GPa, respectively. In this case, significant differences were not observed among the hardness and elastic modulus at different oxygenation states. However, the hardness and elastic modulus for as-grown and oxygenated YBa{sub 2}Cu{sub 3}O{sub 7−δ} single crystals were different from that of the a (b) c−plane, and were observed to be slightly higher for the as-grown than for the oxygenated samples. For as-grown and oxygenated samples, we observed hardness values around 4.7 and 2.0 GPa, respectively. Regarding the elastic modulus, the values were 75 and 40 GPa, respectively. The indentation fracture toughness values on the ab- plane for the as-grown and oxygenated YBa{sub 2}Cu{sub 3}O{sub 7−δ} single crystal were 3.7 ± 1.2 and 2.9 ± 1.2 MPa m{sup 1/2}, respectively. For the ab- plane, the scratch resistance of the as-grown sample was higher than that of the oxygenated sample and the scratches under load were deeper for the oxygenated sample. As regards the a (b) c−plane, the scar features were seemingly constant through all the scratch lengths and the scratches under load were deeper and larger for the oxygenated than that for the as-grown sample.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Evolution of Intrinsic and Magnetic Field-Induced Magnetic Anisotropies in Strongly Phase-Separated Manganite Thin Films

Single crystalline thin film (∼ 100 nm) of La{sub 0.18}Pr{sub 0.40}Ca{sub 0.42}MnO{sub 3} is grown on (001) oriented LaAlO{sub 3} substrates and the evolution of anisotropy associated with the supercooling behaviour of the magnetic liquid is studied as a function of temperature and magnetic field. The angle-dependent magnetization measurements ascertain that the easy magnetic axis lies in the plane of the film while the hard axis is along the plane normal. The ratio of the easy and hard axes magnetizations (M{sub ||} and M{sub ⊥}) measured at 10 K, viz., M{sub ||}/M{sub ⊥} (10 K) = 2.6, confirms the strongly anisotropic nature of the film. The easy axis ferromagnetic (FM) transition temperature (T{sub C}) is smaller than that along the hard axis. The giant hysteresis in FCC–FCW M–T, which manifests the magnetic liquid behaviour of the strongly phase-separated manganites is appreciably narrowed along the hard axis. The strain glass state is also less dominant along the easy axis. The analysis of the M–H data brings out that the easy axis remanence (M{sub r||}) shows a nonlinear temperature dependence, while the one corresponding to the hard axis (M{sub r⊥}) shows a nearly linear behaviour. The coercivity (H{sub C}) follows a law of the type H{sub C}(T)=H{sub C}(0)(1−AT{sup b}). The value of exponent b ∼ 0.5 for single-domain particles, but in the present case, the best fit to the experimental data yields the exponent b ≈ 0.25 for both H{sub C||} and H{sub C⊥}. The smaller value of the exponent is attributed to the non-canonical nature of the ferromagnetic state and the associated strongly phase-separated nature of the LPCMO thin film.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

{sup 75}As NMR and XRD Study of Structural and Electronic Inhomogeneities in Ba(Fe{sub 1−x}Ni{sub x}){sub 2}As{sub 2}

We have used {sup 75}As NMR and x-ray diffraction analysis to study the structural and electronic inhomogeneities in Ba(Fe{sub 1−x}Ni{sub x}){sub 2}As{sub 2} crystals with x near the border of the antiferromagnetic domain. Unequal nickel population of the equivalent Fe planes and rather homogeneous distribution of Ni inside the planes have been found in the well-ordered single crystal with x = 0.036. Below 40 K a signal wipeout of {sup 75}As NMR spectra is observed for the crystals with x = 0.036 and 0.037. This fact together with spin-lattice relaxation peculiarities is treated a result of the system glassy behavior in this region of the phase diagram. The {sup 75}As NMR data also indicate on partial suppression of antiferromagnetic spin fluctuations around the Ni impurity in these crystals at low temperatures.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Control of Both Superconducting Critical Temperature and Critical Current by Means of Electric-Field-Induced Reconfigurable Strain

The controlled modification of superconductivity by any means is a long-standing issue in low-temperature physics. In this work, we present data on the control of the superconducting properties of conventional low critical-temperature (T{sub C}) Nb thin films with thickness (d{sub Nb}) = 15 and 20 nm under application of reconfigurable strain, S induced by an external electric field, and E{sub ex} to a piezoelectric (PE) single crystal, namely (1 − x)Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3} − x PbTiO{sub 3} (PMN-PT) with x = 0.30–0.31. The experimental results (reduction of T{sub C} and critical current (J{sub C}) on the order of 6% and 90–100%, respectively) are nicely reproduced with a phenomenological model that incorporates the constitutive relation S(E{sub ex}) that describes the electro-mechanical response of the PE crystal to well-established formulas that describe T{sub C} and J{sub C} of the SC thin films.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Structure and Magnetic Properties of Graded (001)-Oriented FePt Films Prepared by Magnetron Sputtering and Rapid Thermal Annealing

L1{sub 0}-FePt/[Fe/Pt]{sub 27} multilayer films were prepared on (100)-oriented single-crystal MgO substrates. Structural analysis indicates epitaxial growth of the L1{sub 0}-FePt films during high-temperature deposition. The room-temperature-deposited [Fe/Pt]{sub 27} multilayer exhibits the fcc-FePt structure grown epitaxially on the L1{sub 0}-FePt base layer. The degree of chemical order and thereby the anisotropy of the top layer has been controlled by varying the temperature of a post-deposition annealing process. Compared with the as-deposited films, coercivities of the films annealed below 400 {sup ∘}C are substantially decreased by introducing the formation of a graded anisotropy in the partially ordered top layer. Coercivities decrease for annealing temperatures that are greater than 400 {sup ∘}C due to improved ordering of the top layer.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Equilibrium Properties of the Mixed State in Superconducting Niobium in a Transverse Magnetic Field: Experiment and Theoretical Model

Equilibrium magnetic properties of the mixed state in type II superconductors were studied on high-purity film and single-crystal niobium samples with different Ginzburg-Landau parameters in perpendicular and parallel magnetic fields using dc magnetometry and scanning Hall-probe microscopy. The magnetization curve for samples with unity demagnetizing factor (slabs in perpendicular field) was obtained for the first time. It was found that none of the existing theories is consistent with these new data. To address this problem, a theoretical model is developed and comprehensively validated. The new model describes the mixed state in an averaged limit, i.e., without detailing the samples’ magnetic structure and therefore ignoring the surface current and interactions between the structural units (vortices). At low values of the Ginzburg-Landau parameter, it converts to the model of Peierls and London for the intermediate state in type I superconductors. The model quantitatively describes the magnetization curve for the perpendicular field and provides new insights into the properties of the mixed state, including properties of individual vortices. In particular, it suggests that description of the vortex matter in superconductors of the transverse geometry as a “gas-like” system of non-interacting vortices is more appropriate than the frequently used solid-like scenarios.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Heat Capacity and Mössbauer Study of Self-Flux Grown FeTe Single Crystal

We report mainly the heat capacity and Mössbauer study of self-flux grown FeTe single crystal, which is a ground state compound of the Fe chalcogenides superconducting series i.e. FeTe{sub 1−x}(Se/S){sub x} The as grown FeTe single crystal is large enough to the tune of a few centimetres and the same crystallizes in tetragonal structure having space group of P4/nmm. FeTe shows the structural/magnetic phase transition at 70 K in both magnetic and resistivity measurements. Heat capacity measurement also confirms the coupled structural/magnetic transition at the same temperature. The Debye model fitting of low temperature (below 70 K) heat capacity exhibited Debye temperature (𝜃{sub D}) to be 324 K. Mössbauer spectra are performed at 300 and 5 K. The 300-K spectra showed two paramagnetic doublets and the 5-K spectra exhibited hyperfine magnetic sextet with an average hyperfine field of 10.6 Tesla matching with the results of Yoshikazu Mizuguchi et al.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

The Vanishing Superfluid Density in Cuprates—and Why It Matters

Recently, we have released the results of a comprehensive study of a couple thousand single-crystal La{sub 2−x}Sr{sub x}CuO{sub 4} films, covering densely the entire overdoped side of the phase diagram (Božović et al. Nature 536, 309–311, 2016; Wu et al. Nature 547, 432–435, 2017). Here, we review the key experimental findings, place them in the context of other important well-established facts and observations, and discuss their implications for our understanding of high-temperature superconductivity in cuprates. We conclude that it involves some new physics that requires going beyond the standard Fermi liquid description of the normal state and Bardeen-Cooper-Schrieffer description of the superconducting state.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

Preparation of Fine Single Crystals of Rutheno-Cuprates by the Self-Flux Method with Alumina Boats

We investigate the single crystal growth of rutheno-cuprates, which are known to be magnetic superconductors. We attempted the single crystal growth of two systems, RuSr{sub 2}GdCu{sub 2}O{sub 8−δ} (RuGd-1212) and RuSr{sub 2}(Gd,Ce){sub 2}Cu{sub 2}O{sub 10−δ} (RuGd-1222), by the self-flux method with alumina boats. Fine cubic crystals of RuGd-1212 with a side length of approximately 5 μ m were obtained by slow cooling from 1350 to 940 {sup ∘}C. Plate-like RuGd-1222 crystals with a smooth plane were obtained at the surface of the precursor pellet. RuGd-1222 was more stable at high temperatures than RuGd-1212 and was also superconductive, but its superconductivity weakened as the cooling rate decreased. This weakening was induced by decomposition. Therefore, high-quality RuGd-1222 single crystals were difficult to obtain, and we failed to extract only the smooth planar crystal part. As a modified synthesis technique, we mixed a precursor containing Ru–Sr–Gd–Ce flux with RuGd-1222 powders and gradually cooled the mixture from 1350 to 1090 {sup ∘}C. A plate-like RuGd-1222 sample with a smooth surface and a size of 70 × 30μm{sup 2} was obtained from the side surface of the precursor pellet. By this technique, we could separate the planar crystal part. Semiquantitative composition analysis confirmed this planar crystal as a RuGd-1222 phase. The X-ray diffraction peak suggested the (0014) plane, implying that the plate-like precipitates are c-axis-oriented RuGd-1222 single crystals.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

High-Field Magneto-Conductivity Analysis of Bi{sub 2}Se{sub 3} Single Crystal

We report the high-field (up to 14 Tesla) magneto-conductivity analysis of Bi{sub 2}Se{sub 3} topological insulator grown via the self-flux method. The detailed experimental investigations including crystal growth as well as the electrical, thermal, and spectroscopic characterizations of the resultant Bi{sub 2}Se{sub 3} single crystal are already reported by some of us. The current letter deals with high-field magneto-conductivity analysis in terms of Hikami Larkin Nagaoka (HLN) model, which revealed that the electronic conduction is dominated by both surface state-driven weak anti-localization (WAL), as well as the bulk weak localization (WL) states. Further, by applying the HLN equation, we have extracted the fitting parameters, i.e., phase coherence length (l{sub φ}) and the pre-factor (α). Here, the magneto-conductivity data is fitted up to ± 5 Tesla, but in order to extract reliable fitting parameters, the same is fitted at much lower magnetic fields, i.e., up to ± 1 Tesla. The value of the HLN coefficient (α), extracted from the HLN equation exhibited values close to − 1.0, indicating both WAL and WL contributions. On the other hand, the extracted l{sub φ} is seen to decrease from 11.125 to 5.576 nm as the temperature is increased from 5 to 200 K, respectively. Summarily, the short letter discusses primarily the temperature-dependent magneto-conductivity analysis of pristine Bi{sub 2}Se{sub 3} single crystal by the HLN model.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗