Physica E-Low-Dimensional Systems & Nanostructures

Article	Citations
Editorial Board	126
Effect of global charge on stability and electronic properties of B36N36 cage and isomers	109
Structural, morphological, optical, magnetic and impedance spectroscopic properties of Ni0·5Fe2·5O4 nanoparticles synthesized by the self-combustion method	84
Flux dependent current rectification in geometrically symmetric interconnected triple-dot Aharanov-Bohm interferometer	74
In-situ lattice structure analysis in sp2 hybridization of stable carbon isotopes: Precision modelling of temperature	63
Influence of Coulomb blockade effect on the differential capacitance of two-island system: A quantum Monte Carlo study	59
The role of thermal vibrations in transformation of structure transition for sodium nitrate in a restricted geometry	54
Resonance and Anti-resonance in transport through quantum dots-Majorana bound states hybrid structure	50
Observation of voltage dependent negative differential resistance (NDR) in SnS2-GO nanocomposites	48
Quantum transport simulations of α-In2Se3 antiferroelectric tunnel junctions	48
Structural stability and electronic properties of Er nanowire on Si(001)	45
Leveraging machine learning to harness non-parabolic effects in semiconductor heterostructures	44
Electric and thermoelectric response for Weyl and multi-Weyl semimetals in planar Hall configurations including the effects of strain	42
Theoretical modelling of graphene system for nano-electromechanical resonator and force sensor	42
Structural and electronic properties of AlGaN nanowires modulated by Al component and sectional size: A first principles study with DFT+U method	41
Formation of vanadium dioxide nanocrystal arrays via post-growth annealing for stable and energy-efficient switches	39
Exact quantum-mechanical solution for the one-dimensional harmonic oscillator model asymmetrically confined into the infinite well	36
GST and BFO assisted microring resonator for nanoplasmonic applications	35
Optical properties of a quantum well with Razavy confinement potential: Role of applied external fields	35
High thermoelectric power factor in LaV	34
Electrical and shielding properties of epoxy composites with Ni–C and Co–C core-shell nanoparticles	33
Single Zn atom catalyst on Ti2CN2 MXenes for efficient CO oxidation	33
Comment on: “Structural, optical and dielectric studies of Ag nanoparticles decorated by herceptin” [Physica E 114 (2019) 113562]	32
Direct correlation between electronic and optical properties of the XC monolayers (X= Si, Ge, and Sn) from first-principles calculations	32
Plasmonic Au-decorated hierarchical p-NiO/n-ZnO heterostructure arrays for enhanced photoelectrochemical water splitting	32

Superconductivity and spin density wave in AA stacked bilayer graphene	31
Advanced THz metasurface biosensor for label-free amino acid detection optimized with stacking ensemble algorithm	31
First-principles exploration of hydrogen evolution ability in MoS2/hBNC/MoSSe vdW trilayer heterojunction for water splitting	31
Fluorescent boron carbide quantum dots synthesized with a low-temperature solvothermal approach for boron neutron capture therapy	31
Electronic structure and terahertz intersubband absorption spectra of phosphorus donor in silicon using a variationally optimized diagonalization method	30
Density functional calculations of atomic structure, charging effect, and static dielectric constant of two-dimensional systems based on B-splines	30
Preparation and room-temperature hydrogen sensing property of flower-like In2O3/SnS2 nanocomposite	30
Structure and stability of Au, Au2 and Au8 cluster on Ni(111) supported h-BN sheet: Role of size and support towards oxygen bond activation	30
Tunable mid-infrared sensing based on graphene-metal hybrid structure	30
Quantum state transfer in ladder systems with cross-correlated disorder	29
Surface-dominant transport properties in MoSe2 nanosheets	29
Stability and electronic properties of α/β-Mo6S6 nanowires encapsulated inside carbon nanotubes	29
Two-dimensional MgP3 monolayer with remarkably tunable bandgap and enhanced visible-light and UV optical absorptions	29
Tuning the crystalline field leads to giant regulated perpendicular magnetic anisotropy by depositing Bi atom onto the MgO surface	29
First principles study on the electronic structure and optical properties of Janus WSeTe with defects and strains	28
Nonlinear screening and charge redistribution in periodically doped graphene	27
Study on the effects of anisotropic effective mass on electronic properties, magnetization and persistent current in semiconductor quantum ring with conical geometry	27
Hybrid quantum dot-graphene layers with improved optical properties in the terahertz spectrum region	26
Enhanced Rashba and exchange effects in bridge-structure graphene on Ni(111) from DFT with spin-orbit coupling calculations	26
Editorial Board	26
Charge engineering in black phosphorene with tunable electronic structures as efficient oxygen evolution electrocatalyst	26
The effect of solvent on the structural, morphological, optical and dielectric properties of SnO2 nanostructures	25
Comment on “Thermo-magnetic properties of the screened Kratzer potential with spatially varying mass under the influence of Aharanov–Bohm (AB) and position-dependent magnetic fields”	25
A mid-infrared ultra-wideband polarization-independent tunable perfect absorber based on Dirac metal materials	25
Constructing a simple Cone–Chain motif to significantly enhance the first hyperpolarizability of horn-shaped carbon nanocones	24
The examination of the electrical properties of Al/Mg2Si/p-Si Schottky diodes with an ecofriendly interfacial layer depending on temperature and frequency	24
The time-dependent polaron frame	24
The effect of dielectric slab between photorefractive crystal and graded-index medium on the surface wave properties	24
Transformation of polarons into magnetopolarons in GaAs quantum well	24
Entanglement between quantum dots electronic spins and circular polarized cavity photons due to the spin–orbit interaction	24
Ballistic heat conduction characteristics of graphene nanoribbons	23
Persistent quantum confinement in a Germanium quantum dot solid	23
Preparation of reduced graphene oxide decorated two-dimensional WSe2 nanosheet sensor for efficient detection of ethanol gas	23
Thermally switchable and tunable metasurface with polarization independence based on VO2 phase transition	23
Investigation of edge plasmon modes in graphene-black phosphorus double layer strip waveguides	23
Intrinsic valley polarization and anomalous valley Hall effect in monolayer H	23
Excellent sensing based on dual-plasmon induced transparency in graphene metasurface	22
Editorial Board	22
Half-metallic of non-metal-adsorbed AsP and multifunctional two-dimensional spintronic device of impure AsP from first-principles calculations	22
Propagation and excitation properties of nonlinear surface plasmon polaritons in a rectangular barrier	22
Synthesis, crystal structure, BFDH morphology, Hirshfeld surface analysis and electrical characterization of the new bi-(2-amino-5-methylpyridinium) hexa-chlorostannate compound	22
Dose-dependent X-ray sensing behaviour of Cs3Bi2I9: PVDF-HFP nanocomposites	22
Magneto-tunable terahertz absorption in single-layer graphene: A general approach	22
30 seconds procedure for decoration of titania nanotube with noble metals as metal-dielectric spacer materials towards tunable Purcell Factor and plasmon-coupled emission enhancement	21
Two distinguishable fermions entanglement generation and fermionization	21
Tunable electronic structure and Rashba spin splitting of WSe2/WS2 van der Waals heterostructure via strain and electric-field	21
Editorial Board	21
Ultra-narrow bandwidth red-emission carbon quantum dots and their bio-imaging	21
Probing Majorana zero modes by measuring transport through an interacting magnetic impurity	21
Magneto thermoelectric effect of nickel thin film synthesized by RF magnetron sputtering	21

Memory effects and quantum speedup for a quantum emitter near a molybdenum disulfide nanodisk	21
Hybrid photonic-plasmonic mode-coupling induced enhancement of the spontaneous emission rate of CdS/CdSe quantum emitters	20
A novel method for production of core-shell nanoparticles and its energy storage application	20
Ultrafast response solar-blind UV sensor based on ZnGa2O4 nanowire bridge arrays	20
Size-controllable synthesis of 2D Mn3O4 triangular-shaped nanosheets by thermal chemical vapor deposition	20
Superconductivity and charge density wave in transition metal chalcogenides: A first principle study	20
Quantization of Foster mesoscopic circuit and DC–pumped Josephson parametric amplifier from fractal measure arguments	20
Highly sensitive toluene sensor based on porous core-shell-structured In2O3–ZnO nanofibers under UV irradiation at room temperature	20
Dynamic conductivity of multilayer graphene during pulsed mechanical activation of a composite (polypropylene - graphene nanoplatelets)	20
Electron trapping via magnetic and laser fields in gapped graphene quantum dots	19
Application feasibility of palladium-decorated reduced graphene oxide as a CH4 gas nano-sensor from the perspective of the van der Waals corrected DFT computations	19
Complex impedance, dielectric constant, electric modulus, and conductivity analysis of Cd doped ZnO nanostructures at high temperatures	19
Realization of IR Photodetector based on AGNRs operating in the Atmospheric Windows	19
A methane concentration sensor with heightened sensitivity and D-shaped cross-section U-shaped channel utilizing the principles of surface plasmon resonance	19
Charge and spin currents in mesoscopic rings: Role of next nearest-neighbors Rashba spin–orbit coupling using the Green’s functions equation of motion technique	19
Effects of correlations on phase diagrams of the two-dimensional Su–Schrieffer–Heeger model with the larger topological invariant	19
MoS2: Advanced nanofiller for reinforcing polymer matrix	19
All region analytical modeling of 2-D transition metal dichalcogenide FET by considering effect of fringing field and region-wise mobility	19
Confinement shape effects on binding energy, transition energy, and oscillator strength of a	18
Strain enhanced thermoelectric performance of Lu2CF2 MXene	18
Retraction notice to“Tunable electronic and optical properties of 2D PtS2/MoS2 van der Waals heterostructure” [Phys. B Condens. Matter. 118 (2020) 113866]	18
Room temperature LPG sensing of highly responsive Ag-doped CuO: SnO2 nanocomposite film	18
Polarization induced self-doping effects and p-n junctions in heterostructures based on F-GaN-H stacking	18
Reconfigurable band alignment WTe2/WSi2As4 van der Waals heterostructures for efficient optoelectronic devices	18
Evaluation of the thermal conductivity coefficient of the strained concentric multi-walled carbon and boron-nitride nanotubes: A molecular dynamics investigation	18
Development of an amperometric biosensor for dopamine using novel mesoporous silicon nanoparticles fabricated via a facile stain etching approach	18
Impurity states of electrons on the surface of a nanotube in a magnetic field	18
Subwavelength confinement of a quantum emitter in ladder configuration adjacent to a nanostructured plasmonic metasurface	17
Broadband and thermally switchable reflective metasurface based on Z-shape InSb for terahertz vortex beam generation	17
In-plane and out-of-plane domain orientation dispersions in 1 to 3 monolayers epitaxial WS2 and MoS2 films on GaN(0001) film/sapphire(0001)	17
Size effects on the structural and physical properties of Cu50Zr50 metallic glass nanoparticles	17
Uncertainty relations in thermodynamics of irreversible processes on a mesoscopic scale	17
Topological phases in few-layer silicene nanoribbon induced by normally applied electric field and Rashba spin-orbit coupling	17
Thermometry in dual quantum dot setup with staircase ground state configuration	17
Surface optical phonon and multi – phonon transitions in YVO4:Eu3+ nanopowders	17
Prediction of thermoelectric properties for monolayer BiSbTeSe2	17
Topological behaviors in Kondo insulators	17
Retraction notice to “Magneto-transport signatures in periodically-driven Weyl and multi-Weyl semimetals” [Phys. E: Low-dimens. Syst. Nanostruct. 144 (2022) 115444]	17
Boosting room temperature response of Pd-based hydrogen sensor by constructing in situ nanoparticles	17
Tuning the electronic transport properties in few-layers GeP	16
Compressive solitary waves in black phosphorene	16
Type-II induced quantum confinement in type-I heterostructured semiconductor nanowires	16
ZnO/Zn2TiO4 composite nanostructures produced by laser ablation in air	16
Structural, electronic, and optical properties of the PhaCBNs monolayers	15
Investigating transition metal (Fe, Co, Ni)-doped biphenylene network as a sensor for SF	15
Deep transfer learning correlation study of electronic and spin properties in buckled III–V monolayers	15
One- and few-particle optics of the valence band in lens-shaped Ge/Si quantum dots	15
Scaling transformations among electron transmission curves for golden self-affine multibarrier structures based on graphene	15
Effect of oxygen atoms adsorption and doping on hexagonal boron nitride	15
Angle-tunable two-photon absorption in twisted graphene systems	15
Structural, electronic, and optical properties of C3B and C3B0·5N0.5 monolayers: A many-body study	14
Mechanical and thermal stability of armchair and zig-zag carbon sheets using classical MD simulation with Tersoff potential	14
DFT+U study on the magnetic properties of 3d transition metal doped β borophene	14
Phase diagram of the antiferromagnetic Ising model on a body-centered cubic lattice with competing exchange interactions under a magnetic field	14
Controllable antiresonance and low-bias negative differential conductance in T-shaped double dots with electron–phonon interaction	14
Polypyrrole sheets composed of nanoparticles as a promising room temperature thermo-electric material	14
Quantum-entanglement entropy and double occupancy in a 1-D Holstein-Hubbard model at half-filling	14
Silver sulphide (Ag2S) quantum dots synthesized from aqueous route with enhanced antimicrobial and dye degradation capabilities	14
Analog/RF performance assessment of ferroelectric junctionless carbon nanotube FETs: A quantum simulation study	14
First-principles study on 2D ferromagnetic semiconductor in Janus single-layer CrXY (X = P, As; Y = Cl, Br, I)	14
Effect of screening on seebeck coefficient in bilayer graphene/AlGaAs electron gas	14
Magnetocaloric effect, magnetic susceptibility and specific heat of tuned quantum dot/ring systems	14
Thin film Weyl semimetals with turning number of Fermi surface greater than unity	14
Terahertz broadband tunable reflective cross-polarization convertor based on complementary cross-shaped graphene metasurface	14
Piezoelectricity of Janus group-III monochalcogenide monolayers, multilayers and their vdW heterostructures: Insight from first-principles calculations	14
Novel NiS/Ag2MoO4 heterostructure nanocomposite: Synthesis, characterization and superior antibacterial and enhanced photocatalytic activity	14
Effects on the electronic properties of multilayer phosphorene due to periodic arrays of vacancies: Band unfolding formalism	14
An ab initio study of the interaction of graphene and silicene with one-, two-, and three-layer planar silicon carbide	14
Artificial optoelectronic synapses based on capture layer of silicon rich oxides	14
Post growth annealing of Ga1-xInxNyAs1-y/GaAs double quantum well structures grown on (100), (311)A, and (311)B GaAs substrates	14
Selective edge hydrogenated armchair ZnO nanoribbons for negative differential resistance based nanoelectronic devices	14
Temperature and inhomogeneity combination effects on collective excitations in three-layer graphene structures	14
Abnormal sign change of angle-dependent magnetoresistance in polycrystalline WTe2 nanoplate	14
Shell-induced modification of plasmon coupling and appearance of fano resonance without symmetry breaking in core/shell heteronanostructures	13
First-principles calculations of optical properties of 2D CaFBr and BaFBr monolayers	13
Janus MoSSe/C3N heterostructures: A flexible anode for lithium/sodium-ion batteries	13
Effects of Si, B doping on PC3 monolayer as anode for Na-ion batteries	13
Thermoelectric transport in a spin–orbit mesoscopic interferometer	13
Enhanced N2 fixation on V2C by transition metal doping: First-principles calculation	13
Quantum entanglement in non-Hermitian Hubbard model	13

Quantum dynamics in low-dimensional systems with position-dependent mass and product-like fractal geometry	13
Quantum coupling and hot-carriers impacts on excitons and optical spectrum of GaN devices	13
Coherent effects in energy absorption in double quantum dot molecule – Metal nanoparticle hybrids	13
Casimir effect associated with fractional laplacian and fractal dimensions	13
Impact of Magnetism on (e-ph) self-energy and thermalization of hot carriers in 2D half-functionalized GeC-hybrid	13
Penta graphene: Investigating the role of external fields and electron/hole doping in enhancing transport performance	13
Enhanced photogalvanic effect in a 2D ferroelectric ZrI2 by interlayer sliding	13
Editorial Board	13
Asymmetric terahertz polarizer based on VO2 composite metasurface	13
Effect of growth parameters on defect structure and optical properties of ultrathin SnO2 films	13
Modeling photocurrent spectra of high-indium-content InGaN disk-in-wire photodiode on silicon substrate	13
The structure, electronic, magnetic and optical properties of the Co-X (X = B, C, N, O or F) codoped single-layer WS2	13
Exploring the structural and electronic properties of GeC/BP van der Waals heterostructures	13
Theoretical expolartion of site selective Perovskites for the application of electronic and optoresponsive memory devices	13
A physicochemically reformed nanostructured graphene oxide-doped indium magnesium oxide film with enhanced electrical properties	13
Scanning tunneling microscopy study of the antiferromagnetic topological insulator MnBi2Se4	13
Tri-functional metamaterials integrated with vanadium dioxide in terahertz regions	13
Role of environmental oxygen and water in the electronic and optical properties of sigma tellurene	13
Quasiparticle interference in doped topological insulators with nematic superconductivity	13
Anisotropic interface characteristics of bilayer GeSe based field effect transistors	12
Tuning the surface chemistry of 2D MXenes for optimizing the micellization of bio-targeted carriers	12
Transition from electromagnetically induced transparency to Electromagnetically Induced Absorption Utilizing Phase-Change Material Vanadium Dioxide Based on Circularly Polarized Waves	12
A comparison study of the structural, electronic, elastic, dielectric and dynamical properties of Zr-based monolayer dioxides (ZrO2) and dichalcogenides (ZrX2; X = S, Se or Te) as well as their Janus	12
Structural and electronic properties of hexagonal MXH (M = C, Si, Ge and Sn; X = N, P, As and Sb) monolayers: A first-principles prediction	12
Predicting BN analogue of 8-16-4 graphyne: In silico insights into its structural, electronic, optical, and thermal transport properties	12
Signal polariton switch achieved by controlling the phases of excitation fields	12
Hydroxyl-assisted globally spontaneous dynamic oxygen migration on biphenylene	12
Coherent and incoherent phonon transport in graphene/h-BN superlattice: A machine learning potential	12
The thickness, temperature and dimensionless electron density effects on the renormalization effective mass in a 2DEG	12
Detection of carcinogenic heavy metals using ZnO nanoribbons (ZnONRs): Ab-initio analysis	12
Study on piezo-phototronic effect of AlZnO thin film flexible ultraviolet photodetector	12
Impurity and geometry effects on the optical rectification spectra of quasi-elliptical double quantum rings	12
Unexpected band gap evolution and high carrier mobility sparked by the orbital variation in two-dimensional GaGeX (X = S, Se, Te)	12
Effect of edge groups on the electronic transport properties of tetrapodal diazatriptycene molecule	12
The experimental study of the surface tension of titanium dioxide–ethylene glycol nanofluids	12
The electronic and piezoelectric properties of Janus monolayer MSi2X2Y2: A first-principles study	12
Floquet transitions “Insulator – Semimetal – Insulator” in 2D crystals with displaced Dirac points	12
Giant thermoelectric figure of merit in fluorine-doped single walled-carbon nanotubes	12
Mechanical ball milling: A sustainable route to induce structural transformations in tungsten disulfide for its photocatalytic applications	12
Strain-controllable high Curie temperature and magnetic anisotropy energy in two-dimensional Fe2Si and Fe2Ge	12
Quantum discord in zigzag graphene nanoribbons	12
CO sensing properties of nanostructured WSe2/GaN and MoSe2/GaN based gas sensors	12
Light-induced Shubnikov-de Haas oscillations and evidence of Dirac Fermions in n-type PbTe single quantum well	11
Regulation of the spin orbit coupling by changing the doping ratio x in the surface of monolayer (SxSe1-x)MSe	11
Synthesis of polycrystalline boron nitride nanotubes with Lead(II) oxide and Iron(III) nitrate nonahydrate as promoters	11
Computational search for efficient single-photon emitters among the substitutional doping defects in two-dimensional GaSe	11
Nickel doped ZnO nanoparticles as a novel photocatalytic and multiferroic semiconductor	11
Computational insights of promising Pd atomic clusters modified WS2 for detecting environmentally toxic gases	11
The influence of annealing environment of ZnO thin film on its optical, structural and photovoltaics performance	11
Robust topological bound states in the continuum in a quantum Hall bar with an anti-dot	11
Structure and interaction between the novel graphene-like planar biphenylene network and DNA: Molecular dynamics simulations	11
Thermal transport across a vacuum gap between two reconstructed Si-nanomembranes	11
Phase transitions in the four-state Potts model with competing exchange interactions: Application of the Wang-Landau algorithm	11
Van der Waals stacking-induced efficient Ohmic contacts and the weak Fermi level pinning effect in MoSi2N4 and WSi2N4 contact with two-dimensional metals	11
Molybdenum nanopillar arrays: Fabrication and engineering	11
Leakage current, electrical properties and density of states extracted using correlated barrier hopping in perovskite layered aurivillius Bi5Ti3FeO15 nanoparticles	11
Temperature and pressure dependent tunable GaAsSb/InGaAs QW heterostructure for application in IR-photodetector	11
The topological in-equivalence of Hall bar and Corbino geometries in coordinate space: Screening theory and direct transport experiments	11
Zero-energy states in the Kitaev finite and semi-infinite model	11
Magnetotransport in Weyl semimetal with and without disorder and the effect of tilted magnetic field	11
UV-activated SnO2 thin film for air-atmospheric oxygen sensing at room temperature	11
Occam’s razor description of sudden energy transitions in a Rabi-driven quantum bit under frequent observation	11
Electronic properties and spintronic applications of r-N-graphyne nanoribbons	11
GeO2 – ZnO nanocomposite rosettes for enhancement of performance in energy technologies: Coupling organic templated synthesis with microwave treatment	11
Reconfigurable spin-wave properties in two-dimensional magnonic crystals formed of diamond and triangular shaped nanomagnets	10
On the spectral response of interdiffused quantum dot ensembles embedded in the intrinsic region of InGaAs/GaAs quantum dot solar cells	10
Electronic Transport Modulation in C-57: A Path Toward Carbon-Based Logic and Switching Devices	10
Enhanced piezoelectricity induced by transition metal atoms adsorption on monolayer and bilayer MoS2	10
Enhanced thermoelectric performance via intralead Coulomb interactions and quantum interference in nanostructures	10
Density functional study of the single-walled Haeckelite AlN nanotubes in square-octagon structure	10
Design and simulation of two-color mid-infrared photoconductors based on intersubband transitions in quantum structures	10
Transport fingerprints of helical edge states in Sierpiński tapestries	10
Capturing magic angles in twisted bilayer graphene from information theory markers	10
Enhancement of the optical response of Fe3	10
Cavities in multilayer homo- and heterostructures	10
Temperature dependence of the electron quantum lifetime in InGaAs/GaAs double quantum well: Fukuyama-Abrahams mechanism	10
Colloidal synthesis of cesium iodide nanocrystals for visible-enhanced photodetection applications	10
The third-order nonlinear optical susceptibility in an ellipsoidal core-shell quantum dot embedded in various dielectric surrounding matrices	10
Giant excitonic magneto-Stark effect in wide GaAs/AlGaAs quantum wells	10
High performance photodetector based on WSe2 p-n homojunction induced by the electron doping from Bi2O2Se	10
Tunable Schottky and ohmic contacts in graphene and Pd3X2Y8(X=P, As; Y=S, Se) monolayer van der Waals heterostructures	10
Optomechanically induced transparency and photon blockade in a graphene coupled nonlinear photonic crystal nanobeam cavity based optomechanical system	10
Determining the dependence of solar cell power conversion efficiency on fabrication parameters in inorganic perovskite types by programming gene expression	10
Magnetic barrier and temperature effects on optical and dynamic properties of exciton-polaron in monolayers transition metal dichalcogenides	10
Rogue-wave statistics in Anderson chains	10
Two-dimensional transition metal dichalcogenides van der Waals heterojunctions with broken-gap for tunnel field-effect transistors applications	10
Theoretical investigations of Sc2C based functionalized MXenes for applications in nanoelectromechanical systems	10
Tunable electronic properties of GeC/BAs van der Waals heterostructure under external electric field and strain	10
Hybridization of three types topological states in graphene plasmonic crystals	10
Tunneling influence on the intersubband optical absorption coefficient and refraction index in biased GaAs/AlGaAs quantum well wires	10
Tunable dual-band linear-to-circular polarization conversion based on the electromagnetically induced transparency utilizing the graphene metamaterial	10
Ab initio study of the electronic, optical, and water-splitting properties of Fe-doped ZnO monolayer	10
Stacking pattern effects on the charge carrier dynamics of the MoS2/BSe heterostructure	10
Quasi-bound states and resonant skew scattering in two-dimensional materials with a Mexican-hat dispersion	10
Coherent transport and thermoelectric effects in pristine and binary alloyed noble metals nanoribbons using first principles	10