Prediction and accelerated laboratory discovery of previously. We have constructed a database of their electronic, magnetic and structural properties 27, which enables us to identify potentially useful electrodespacer materials for future spintronics applica. B 99, 0857 2019 highpressure investigations on the semiheusler compound cumnsb phys. Recently, a new material property of half heusler compounds was predicted based on electronic structure calculations. Magnetism in tetragonal manganeserich heusler compounds. Study of heusler alloys for spintronic application 129 homogeneity. Recently, another family of heusler compounds known as quaternary heusler alloys with chemical formula of xx. Crystal structure, composition and heat treatment were found to be important parameters for determining magnetic properties. The prepared compounds contain ternary cr, rh,ru, ni, pd, and ptbased heusler systems as well as quaternary co2based compounds and compounds of the general formula xx. Halfheusler phases and nanocomposites as emerging highzt thermoelectric materials volume 26 issue 22 s. The effect of pressure and alloying on halfmetallicity of. The crystal structure and noncollinear magnetic structure together with magnetic and spinorbit interactions define the symmetry of the skyrmion structure. Modified beckejohnson potential investigation of half. Oclcs webjunction has pulled together information and resources to assist library staff as they consider how to handle coronavirus.
Numerous and frequentlyupdated resource results are available from this search. For example, ferromagnetic sfmd ptmnsb was discovered1 to display the largest known magnetooptic kerr effect at room temperature sat photon energy v1. We outline the importance of these parameters in the heusler compound mn1. First principles study of full heusler rh tige compound. Certain features of the ab initio codes, such as the capability to calculate polarization based on the modern theory of polarization, or to apply a. Ybbipt has a noncentrosymmetric cubic crystal structure. Many of these compounds exhibit properties relevant to spintronics, such as magnetoresistance, variations of the hall effect, ferro, antiferro, and ferrimagnetism, halfand. The effects of chemical bonding on the topological. Certain features of the ab initio codes, such as the capability to calculate polarization based on the modern theory of polarization, or to apply a finite electric field, are central to the problems.
The search for stable halfmetallic ferromagnets and ferromagnetic semiconductors with curie. Computational investigation of halfheusler compounds for spintronics applications jianhua ma,1, vinay i. Properties of halfheusler compounds tairge by using first. Mar 24, 2015 a method to predict the stability, structure and properties of asyetunreported materials has been devised. Electronic and magnetic properties of x2yz and xyz heusler. Thus the ability of compounds to form b2 structure indicates the possibility of forming new heusler compounds. Pdf halfheusler compounds are an impressive class of materials with a huge potential for different applications such as future energy applications. Tetragonal superstructure of the antiskyrmion hosting. One recent prominent example of a binary semiconductorhalf heusler compound analogue are the topological insulators. Many of these compounds exhibit properties relevant to spintronics, such as magnetoresistance, variations of the hall effect. Description this thesis discusses electromechanical and polar properties in two wellknown classes of materials, perovskite oxides and halfheusler compounds, using firstprinciples calculations. Heusler compoundiiiv semiconductor heterostructures. Slaterpauling curve for fullheusler compounds fullheusler compounds hybridization between coco and mn in minority bands in co 2 mnsige i. Here, the semiconducting halfheusler, cotisb is grown by molecular beam epitaxy and used to explore the both the tunability of heusler compound properties as well as the interface properties of heusler alloys with iiiv and other heusler compounds.
Structural, elastic, electronic, magnetic and thermoelectric. The heusler sat2x typed and halfheusler satx type, t transition metal, xmetal or metalloidd structures have produced a number of unusually interesting compounds. Halfheusler phases and nanocomposites as emerging highzt. Half heusler phases and nanocomposites as emerging highzt thermoelectric materials volume 26 issue 22 s. In recent years, halfheusler hh compounds has become the center of research attention due to their thermal stability, mechanical strength, nontoxicity and costeffectiveness.
Electronic structure and physical properties of heusler compounds. First principle simulation was carried out to calculate the electronic structure and the obtained results were compared among different compounds. We demonstrate that the electronic structure of unstrained laptbi as a prototype system exhibits a distinct bandinversion feature. Since 20, the verifiable zt of halfheusler compounds has risen from 1 to near 1.
Gaultois, bryce meredig, and arthur mar, department of chemistry, university of alberta, edmonton, ab t6g 2g2 canada. Simple rules for the understanding of heusler compounds. Spinorbit coupling soc removed the degeneracy of vbm, and then decreased the seebeck coefficients and power factor. Dear colleagues, the increasing interest in heusler and halfheusler compounds, since the first discovery of the 1 st cu 2 mnal heusler compound by the german scientist friedrich heusler in 1903, passing 100,000 publications in 2017, with more than 1500 reported compounds, is due to their high potential for a wide variety of. Firstprinciples study of electromechanical and polar. Crystal structure of heusler compounds springerlink. Hegde,2 kamaram munira,3 yunkun xie,1 sahar keshavarz,3,4 david t. Heusler compounds are ternary intermetallic facecentered cubic fcc crystals with the general formula xyz often called half heusler or x2yz full heusler, in which x and y are typically transition metals and z is a main group element. As we see, all three compounds are narrow band gap semiconductors. Similar to halfheusler materials, this structure consists of four interpenetrating fcc sublattices, two of.
We have investigated the electronic structures of various potentially halfmetallic heusler compounds with the tranblaha modified beckejohnson tbmbjlda potential within the density functional theory. In this paper, we describe a computational investigation covering 378 half heusler compounds using rstprinciples methods. Our data show clear spinorbit splitting of the surface bands and the kramers degeneracy of spins at the and m. Electronic, and thermoelectric properties of halfheusler. Gilleben 10 has theoretically predicted and reported many full and half heusler compounds using density functional theory. The half heusler structure is based on the heusler structural class at2x of numerous intermetallic compounds, with space group fm3m s225d whose point group contains all 48 cubic operations. Engineering halfheusler thermoelectric materials using zintl. We single out the systems that remain cubic from those that most likely become tetragonal. G suresh 1,2magnetic materials lab, indian institute of technology bombay, mumbai, india email.
Johnson, martin joseph, superconductivity in ternary rare earth palladium heusler compounds 1984. Quite dramatically, the ground state inertial defect jumps from. The half heusler alloys 7, 8 have also been prepared and reported by many researchers. From the compressive to tensile strain, the band gap gradually increases from 0. Starting from a large set of cubic parent systems, the response to tetragonal distortions is studied in detail. These numbers are in good agreement with those found previously 24 26. In figure 3, we show the calculated energy band structures for zrdoped ticosb halfheusler compounds. Engineering halfheusler thermoelectric materials using. Our results show that the z 2 topological order is due to a single band inversion at the. Slaterpauling curve for full heusler compounds full heusler compounds hybridization between coco and mn in minority bands in co 2 mnsige i. The x atoms occupy the wyckoff position 8c 14, 14, 14, the y and the z atoms are located at 4a 0, 0, 0 and 4b 12, 12, 12, respectively.
Using firstprinciples calculations within density functional theory, we explore the feasibility of converting ternary halfheusler compounds into a new class of threedimensional topological insulators 3dti. New heusler compounds and their properties benjamin balke, gerhard h. Halfheusler compounds as a new class of threedimensional. Supporting information remarkably high thermoelectric. The nomenclature in literature varies a lot, ranging from sorting the elements alphabetically. Using firstprinciples calculations within density functional theory, we explore the feasibility of converting ternary halfheusler compounds into a new class. In this chapter, a detailed description of the crystal structure as well as different types of atomic disorder are given. Structural, electronic and magnetic properties of x2yz heusler. It was also discovered that it is possible to leave. Abstractthis study is focused on certain heusler alloys to search for half. Prediction and accelerated laboratory discovery of. Mgagas structured half heusler alloys are found to be thermo electric materials. Butler3,4, y 1department of electrical and computer engineering, university of virginia, charlottesville,va22904, usa. Thermoelectric properties of heavilydoped fe2yz fullheusler.
The x and y atoms have a distinct cationic character, whereas z can be seen as the anionic counterpart. Basics and prospective of magnetic heusler compounds. Firstprinciples investigation of the effect of mdoped m. Semimetallic antiferromagnetism in the halfheusler compound. In halfmetallic heusler compounds, the top edge and bottom edge of the highest. Apr 26, 2017 the electronic structures, optical and thermoelectric properties of ternary half heusler compound tairge were investigated by using the firstprinciples and boltzmann transport theory.
Fecher, and claudia felser abstract spintronics is a multidisciplinary. A critical study of the elastic properties and stability of. Recently, a new material property of halfheusler compounds was predicted based on electronic structure calculations. The heusler compounds x 2 yz crystallize in the cubic space group f m 3. A semiconductor to metal transition is examined by substitutionally alloying ni for co.
Skyrmions in noncentrosymmetric magnets are vortexlike spin arrangements, viewed as potential candidates for information storage devices. A mass research interest has been focused on the heusler compounds only after the discovery of its peculiar half metallic property in nimnsb from an ab initio approach. Observation of unusual topological surface states in half. Crystal structure of new heusler compounds request pdf. Dear colleagues, the increasing interest in heusler and half heusler compounds, since the first discovery of the 1 st cu 2 mnal heusler compound by the german scientist friedrich heusler in 1903, passing 100,000 publications in 2017, with more than 1500 reported compounds, is due to their high potential for a wide variety of. Chapter 2 new heusler compounds and their properties. Heusler compounds are a class of ternary intermetallics, including full heusler x2yz with the l21 structure, and half heusler xyz with c1b. In this paper, we present measurements of the metallic surface electronic structure in three members of this family, using angleresolved photoemission spectroscopy arpes. Halfheusler compounds based on xnisn and xcosb x ti, zr or hf have rapidly become important thermoelectric materials for converting waste heat into electricity. The constituent elements of the heusler compounds cover almost the whole periodic table, as shown.
Oct 15, 2014 ternary semiconducting or metallic half heusler compounds with an atomic composition 1. Transport and optical properties of the gapless heusler compound ptysb. Heusler compounds are a remarkable class of materials with more than members and a wide range of extraordinary multifunctionalities including halfmetallic hightemperature ferri and ferromagnets, multiferroics, shape memory alloys, and tunable topological insulators with a high potential for spintronics, energy technologies, and magnetocaloric applications. A comprehensive study of the total energy of manganeserich heusler compounds using density functional theory is presented. In native states, these halfheusler compounds are identified as being topologically nontrivial semimetals, or. In general, heusler compounds crystallize in the cu 2 mnaltype structure but in many cases certain types of disorder are observed. Moreover, for iiiviiiv half heusler compounds the valent orbital are usually fixed and the conduct orbital move away from fermi level, whereas for iiviiivi half heusler compounds the conduct orbital tend to be fixed and the valent orbital move away from fermi level as the lattice constant is reduced.
Tetragonally distorted heusler compounds have attracted interest in the field of spintronics, in particular, for spintorque applications, owing to their magnetic anisotropy in the perpendicular axes 7 8 9. Situated in a local v 6 environment, the v 3 barrier is caused by the aldehyde group and communicated through the aromatic. Topological quantum materials represent a new class of matter with both exotic physical phenomena and novel application potentials. Remarkably high thermoelectric efficiency of the half heusler compounds bxga x be, mg, and ca hailong sun, chuanlu yang, meishan wang, xiaoguang ma school of physics and optoelectronics engineering, ludong university, yantai 264025, the peoples republic of china corresponding author. A method to predict the stability, structure and properties of asyetunreported materials has been devised. However, formatting rules can vary widely between applications and fields of interest or study. Using firstprinciples calculations within density functional theory, we explore the feasibility of converting ternary half heusler compounds into a new class. Special heusler compounds for spintronic applications.
The crystal structure was found out from the powder xray diffraction xrd data. Supporting information highthroughput machinelearningdriven synthesis of fullheusler compounds anton o. In this paper the many properties of heusler compounds will first be introduced, then their successful application in metallic spintronic devices magnetic tunnel junctions will be described, followed by a discussion on their applications beyond metallic spintronics and their integration with the well established iiiv compound semiconductors and devices. Superconductivity in ternary rare earth palladium heusler.
New materials must be found for satisfying the different types of requirement. May 17, 2016 half heusler compounds based on xnisn and xcosb x ti, zr or hf have rapidly become important thermoelectric materials for converting waste heat into electricity. Yz quaternary heusler compounds crystallize in the limgpdsntype crystal structure 10, 11 with f43m symmetry. Review of heusler compounds zhaoqiang bai,1, 2 lei shen,1, guchang han,2 and yuan ping feng1, 1 department of physics, national university of singapore, 2 science drive 3, singapore 117542, singapore 2 data storage institute, agency for science, technology and research, 5 engineering drive 1, singapore 117608, singapore abstract. A further analysis of the experimental results reveals a close structural relationship between these two compounds. Tetragonal superstructure of the antiskyrmion hosting heusler. Computational investigation of halfheusler compounds for.
The effects of chemical bonding on the topological property. The electronic structures, optical and thermoelectric properties of ternary halfheusler compound tairge were investigated by using the firstprinciples and boltzmann transport theory. Thermoelectric properties of heavilydoped fe2yz full. For 18valence electron abx materials, 15 such missing compounds identified to be. Supporting information highthroughput machinelearning. Structural, electronic and magnetic properties of x2yz. Novel materials for energy and spintronic applications article pdf available in semiconductor science and technology 276 june 2012 with 4,414 reads how we measure. Phase change 6 heusler compounds are interesting as magnetocaloric and magnetic shape memory effect materials. Chapter 2 new heusler compounds and their properties benjamin balke, gerhard h.
Rareearth platinum bismuth rptbi has been proposed recently as a potential topological insulator. Combining firstprinciples density functional theory calculations within a hybrid functional approach and boltzmann semiclassical transport theory, we investigate the limits of the rigid band. The xray refinement of the diffraction pattern was done using fullprof suite in order to establish the phase purity of alloys. This structure type can be pictured in terms of an underlying bcc arrangement of atomic sites with lattice constant a2, with atom a at s0,0,0d,xats 1 2, 2. Besides half metallicity, the other interesting properties of these compounds include high curie temperature, low thermal conductivity, high spin polarization, and are. Pdf in the recent decade, the family of heusler compounds has attracted tremendous scientific and technological interest in the field of.
With such a large number of combinations of elements, many compounds have only recently been predicted theoretically to be thermodynamically stable and have yet to be. Pdf files of publications since 1999 plus a few earlier evidence for superconductivity in rb metal above 55 gpa pressure phys. Heusler compounds are a large group of intermetallic compounds with 1500 members that have a wide range of material properties and can be thought of as the metallic equivalents to the perovskite complex metal oxides. In native states, these halfheusler compounds are identified as being topologically nontrivial semimetals, or nontrivial metals, or trivial insulators, which can be turned into insulating thin films on suitable substrates. Spin polarised heusler compounds computer file, 2006. Topological electronic structure in halfheusler topological. Here, the semiconducting half heusler, cotisb is grown by molecular beam epitaxy and used to explore the both the tunability of heusler compound properties as well as the interface properties of heusler alloys with iiiv and other heusler compounds. Ternary semiconducting or metallic halfheusler compounds with an atomic composition 1. New heusler compounds in nimnin and nimnsn alloys nature. Semimetallic antiferromagnetism in the halfheusler. In figure 3, we show the calculated energy band structures for zrdoped ticosb half heusler compounds. A critical study of the elastic properties and stability. Heusler compounds are magnetic intermetallics with facecentered cubic crystal structure and a composition of xyz halfheuslers or x 2 yz fullheuslers, where x and y are transition metals and z is in the pblock.