scholarly journals Electronic phase-crossover and room temperature ferromagnetism in a two-dimensional (2D) spin lattice

RSC Advances ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 946-952
Author(s):  
A. K. Nair ◽  
S. J. Ray
Keyword(s):  
High Temperature ◽  
Curie Temperature ◽  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Magnetic Ordering ◽  
Metallic State ◽  
Two Dimensional ◽  
Half Metallic ◽  
Spin Lattice ◽  
Electronic Phase

In the presence of strain, high temperature magnetic ordering in Cr2Ge2Te6 was observed with electronic phase crossover from semiconducting to half-metallic state. On coupling strain and electric field, the Curie temperature reaches 331 K.

The High-temperature Modification of LuAgSn and High-pressure High-temperature Experiments on DyAgSn, HoAgSn, and YbAgSn

2008 ◽  
Vol 63 (2) ◽  
pp. 193-198 ◽  
Author(s):  
Birgit Heying ◽  
Ute Ch. Rodewald ◽  
Gunter Heymann ◽  
Wilfried Hermes ◽  
Falko M. Schappacher ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Room Temperature ◽  
Magnetic Ordering ◽  
Two Dimensional ◽  
Arc Melting ◽  
Temperature Modification ◽  
High Pressure High Temperature ◽  
High Temperature Modification ◽  
Related Phase

The high-temperature modification of LuAgSn was obtained by arc-melting an equiatomic mixture of the elements followed by quenching the melt on a water-cooled copper crucible. HT-LuAgSn crystallizes with the NdPtSb-type structure, space group P63mc: a = 463.5(1), c = 723.2(1) pm, wR2 = 0.0270, 151 F2, and 11 variables. The silver and tin atoms build up two-dimensional, puckered [Ag3Sn3] networks (276 pm Ag-Sn) that are charge-balanced and separated by the lutetium atoms. The Ag-Sn distances between the [Ag3Sn3] layers of 294 pm are much longer. Single crystals of isotypic DyAgSn (a = 468.3(1), c = 734.4(1) pm, wR2 = 0.0343, 411 F2, and 11 variables) and HoAgSn (a = 467.2(1), c = 731.7(2) pm, wR2 = 0.0318, 330 F2, and 11 variables) were obtained from arc-melted samples. Under high-pressure (up to 12.2 GPa) and high-temperature (up to 1470 K) conditions, no transitions to a ZrNiAl-related phase have been observed for DyAgSn, HoAgSn, and YbAgSn. HT-TmAgSn shows Curie-Weiss paramagnetism with μeff = 7.53(1) μB/Tm atom and θP = −15.0(5) K. No magnetic ordering was evident down to 3 K. HT-LuAgSn is a Pauli paramagnet. Room-temperature 119Sn Mössbauer spectra of HT-TmAgSn and HT-LuAgSn show singlet resonances with isomer shifts of 1.78(1) and 1.72(1) mm/s, respectively

scholarly journals A First-Principle Study of Monolayer Transition Metal Carbon Trichalcogenides

2021 ◽  
Author(s):  
Muhammad Yar Khan ◽  
Yan Liu ◽  
Tao Wang ◽  
Hu Long ◽  
Miaogen Chen ◽  
...  
Keyword(s):  
Phonon Dispersion ◽  
Magnetic Ordering ◽  
Dimensional Structure ◽  
First Principle ◽  
Two Dimensional ◽  
Biaxial Strain ◽  
Half Metallic ◽  
First Principle Calculations ◽  
Potential Applications ◽  
External Strain

AbstractMonolayer MnCX3 metal–carbon trichalcogenides have been investigated by using the first-principle calculations. The compounds show half-metallic ferromagnetic characters. Our results reveal that their electronic and magnetic properties can be altered by applying uniaxial or biaxial strain. By tuning the strength of the external strain, the electronic bandgap and magnetic ordering of the compounds change and result in a phase transition from the half-metallic to the semiconducting phase. Furthermore, the vibrational and thermodynamic stability of the two-dimensional structure has been verified by calculating the phonon dispersion and molecular dynamics. Our study paves guidance for the potential applications of these two mono-layers in the future for spintronics and straintronics devices.

Room-temperature Ferromagnetism in Two-dimensional Transition Metal Borides: A First-principles Investigation

2021 ◽  
Author(s):  
Fang Wu ◽  
Min Dou ◽  
Huan Li ◽  
Yunfei Liu ◽  
Qingnian Yao ◽  
...  
Keyword(s):  
Transition Metal ◽  
First Principles ◽  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Ferromagnetic Materials ◽  
Information Storage ◽  
Two Dimensional ◽  
Storage Media ◽  
Metal Borides ◽  
Generation Information

It is important to predict new two-dimensional (2D) ferromagnetic materials for next-generation information storage media. However, discovered 2D ferromagnetic materials are still rare. Here, we explored that 2D transition metal...

Room-Temperature Ferromagnetism in Co-Doped SrTiO3 Nanofibres

2012 ◽  
Vol 512-515 ◽  
pp. 1438-1441
Author(s):  
Wei Zhang ◽  
He Ping Li ◽  
Wei Pan
Keyword(s):  
Room Temperature ◽  
Oxygen Vacancies ◽  
Room Temperature Ferromagnetism ◽  
Sol Gel ◽  
Magnetic Ordering ◽  
Second Phase ◽  
Co Doped

In this article, Co-doped SrTiO3 nanofibres have been prepared by electrospinning from a sol-gel precursor and the following calcination at 923K. XRD results confirmed that no second phase was formed, and Co ions successfully occupied the Ti sites. By annealing in hydrogen, oxygen vacancies and (Co-H-Co) were formed, which both contributed to the magnetic ordering in SrTi1-xCoxO3 nanofibres are at 300K.

Comparison of the Incorporation of Various Transition Metals into GaN by MOCVD

2006 ◽  
Vol 955 ◽  
Author(s):  
Matthew H Kane ◽  
William Fenwick ◽  
Nola Li ◽  
Shalini Gupta ◽  
Eun Hyun Park ◽  
...  
Keyword(s):  
Transition Metals ◽  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Magnetic Hysteresis ◽  
Chemical Vapor ◽  
Magnetic Ordering ◽  
Growth Conditions ◽  
Shallow Donor ◽  
Organic Chemical ◽  
Secondary Phases

ABSTRACTThe incorporation of transition metals in GaN has long been of interest in spintronics due to theoretical predictions of room temperature ferromagnetism in these materials. However, the mechanism of the observed ferromagnetism of the nitride-based DMS is still controversial, and may originate from a carrier-mediated, defect-related or nanoscale clustering mechanism. In this work, we present a comparative study of the incorporation of various transition metals and their effect on the optical, structural, and magnetic properties of GaN. Metal-organic chemical vapor deposition (MOCVD) has been employed to produce epitaxial films of varying thickness and manganese and iron doping using bis-cyclopentyldienyl(magnanese,iron) as the transition metal sources. High-resolution X-ray diffraction reveals no secondary phases under optimized growth conditions. Magnetic hysteresis is observed at room temperature in both GaMnN and GaFeN, though the strength of the magnetic ordering is roughly an order of magnitude weaker in the Fe-alloyed samples. Increasing Mn concentrations significantly affect long-range lattice ordering, and the observation of local vibrational modes (LVMs) supports the formation of nitrogen vacancies, even under optimized MOCVD growth conditions. Such vacancies form shallow donor complexes and thus contribute to self-compensation. A disorder-induced mode at 300 cm−1 and a LVM due to vacancies at 669 cm-1 were revealed by Raman spectroscopy.

scholarly journals Nearly Room-Temperature Ferromagnetism in a Pressure-Induced Correlated Metallic State of the van der Waals Insulator CrGeTe3

2021 ◽  
Vol 127 (21) ◽  
Author(s):  
Dilip Bhoi ◽  
Jun Gouchi ◽  
Naoka Hiraoka ◽  
Yufeng Zhang ◽  
Norio Ogita ◽  
...  
Keyword(s):  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Van Der Waals ◽  
Metallic State

Massive Vacancy Concentration Yields Strong Room-Temperature Ferromagnetism in Two-Dimensional ZnO

Nano Letters ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 7085-7092 ◽  
Author(s):  
Xin Yin ◽  
Yizhan Wang ◽  
Ryan Jacobs ◽  
Yeqi Shi ◽  
Izabela Szlufarska ◽  
...  
Keyword(s):  
Room Temperature ◽  
Vacancy Concentration ◽  
Room Temperature Ferromagnetism ◽  
Two Dimensional
Sign in / Sign up

Export Citation Format

Share Document