First-order phase transitions in EuCo<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow /><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>P<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow /><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math> and SrNi<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow /><m

Huhnt, C.; Schlabitz, W.; Wurth, A.; Mewis, A.; Reehuis, M.

doi:10.1103/physrevb.56.13796

Cited by 63 publications

(46 citation statements)

References 15 publications

(18 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We also note that pressure-induced superconductivity in CaFe 2 As 2 has been observed close to the OcT transition, and within the hysteretic region associated with that transition and, therefore, should be studied carefully under hydrostatic conditions. The loss of magnetism in the cT phase is largely due to changes in the band structure that depletes Fe 3d DOS at E F , a behavior that is analogous to other 122 type compounds 19,20,21,23 and qualitatively consistent with previous theoretical calculations. 15,24,26 …”

Section: Discussionsupporting

confidence: 72%

Lattice collapse and quenching of magnetism inCaFe2As2under pressure: A single-crystal neutron and x-ray diffraction investigation

et al. 2009

View full text Add to dashboard Cite

Single crystal neutron and high-energy x-ray diffraction have identified the phase lines corresponding to transitions between the ambient-pressure tetragonal (T), the antiferromagnetic orthorhombic (O) and the nonmagnetic collapsed tetragonal (cT) phases of CaFe2As2. We find no evidence of additional structures for pressures up to 2.5 GPa (at 300 K). Both the T-cT and O-cT transitions exhibit significant hysteresis effects and we demonstrate that coexistence of the O and cT phases can occur if a non-hydrostatic component of pressure is present. Measurements of the magnetic diffraction peaks show no change in the magnetic structure or ordered moment as a function of pressure in the O phase and we find no evidence of magnetic ordering in the cT phase. Band structure calculations show that the transition results in a strong decrease of the iron 3d density of states at the Fermi energy, consistent with a loss of the magnetic moment.PACS numbers: 61.50. Ks, 61.05.fm, 74.70.Dd The discovery 1,2 of pressure-induced superconductivity in CaFe 2 As 2 has opened an exciting new avenue for investigations of the relationship between magnetism, superconductivity, and lattice instabilities in the iron arsenide family of superconductors. Features found in the compositional phase diagrams of the iron arsenides, 3 such as a superconducting region at low temperature and finite doping concentrations, are mirrored in the pressure-temperature phase diagrams. Superconductivity appears at either a critical doping, or above some critical pressure in the AFe 2 As 2 (A=Ba, Sr, Ca) or '122' family of compounds, raising questions regarding the role of both electronic doping and pressure, especially in light of the recent observation of pressure induced superconductivity in the related compound, LaFeAsO.4 Does doping simply add charge carriers, or are changes in the chemical pressure, upon doping, important as well? What subtle, or striking, modifications in structure or magnetism occur with doping or pressure, and how are they related to superconductivity? Similar to other members of the AFe 2 As 2 (A=Ba, Sr) family, 5,6,7,8 at ambient pressure CaFe 2 As 2 undergoes a transition from a non-magnetically ordered tetragonal (T) phase (a = 3.879(3)Å, c = 11.740(3)Å) to an antiferromagnetic (AF) orthorhombic (O) phase (a = 5.5312(2)Å, b = 5.4576(2)Å, c = 11.683(1)Å) below approximately 170 K.9,10 In the O phase, Fe moments order in the so called AF2 structure 11 with moments directed along the aaxis of the orthorhombic structure.10 Neutron powder diffraction measurements 12 of CaFe 2 As 2 under hydrostatic pressure found that for p>0.35 GPa (at T=50 K), the antiferromagnetic O phase transforms to a new, non-magnetically ordered, collapsed tetragonal (cT) structure (a = 3.9792(1)Å, c = 10.6379(6)Å) with a dramatic decrease in both the unit cell volume (5%) and the c/a ratio (11%). The transition to the cT phase occurs in close proximity to the pressure at which superconductivity is first observed. 1 Total energy calculations based on this cT s...

show abstract

Section: Discussionsupporting

confidence: 72%

Lattice collapse and quenching of magnetism inCaFe2As2under pressure: A single-crystal neutron and x-ray diffraction investigation

et al. 2009

View full text Add to dashboard Cite

show abstract

“…Either the atoms in the Si position are sufficiently far apart that they are in a non-bonding state, or they are close enough together that they are bonding (typical of single bond distances) 5 . Consequently, depending on the elements in the tetragonal ThCr 2 Si 2 structure, one can induce an isostructural volume collapse with either substitution or pressure 6,7,8,9 . We will refer to the bonding configuration as the "collapsed tetragonal" structure.…”

Section: Introductionmentioning

confidence: 99%

Superconductivity and the effects of pressure and structure in single-crystallineSrNi2P2

et al. 2009

View full text Add to dashboard Cite

Heat capacity, magnetic susceptibility, NMR, and resistivity of SrNi2P2 single crystals are presented, illustrating a purely structural transition at 325 K with no magnetism. Bulk superconductivity is found at 1.4 K. The magnitude of the transition temperature Tc, fits to the heat capacity data, the small upper critical field Hc2 = 390 Oe, and Ginzburg-Landau parameter κ = 2.1 suggests a conventional fully gapped superconductor. With applied pressure a second structural phase transition occurs which results in an 8% reduction in the c/a ratio of lattice parameters. We find that superconductivity persists into this high pressure phase, although the transition temperature is monotonically suppressed with increasing pressure. Comparison of these Ni-P data as well as layered Fe-As and Ni-As superconductor indicates that reduced dimensionality can be a mechanism for increasing the transition temperature.

show abstract

“…In that case, the applied pressure can induced a transition at which P-P transforms from nonbonding to bonding state, and there is also a change in magnetic properties: the magnetism transfers from the Eu(4f) sublattice to the Co(3d) sublattice. [1][2][3] The most salient difference in our case is the reduced dimensionality: the monolayer MoN 2 is a 2D material with atomic thickness. Because of this, the strain needed to induce the transition is small and readily achievable.…”

mentioning

confidence: 99%

Strain-Induced Isostructural and Magnetic Phase Transitions in Monolayer MoN₂

Wang

et al. 2016

Nano Lett.

143

View full text Add to dashboard Cite

The change of bonding status, typically occurring only in chemical processes, could dramatically alter the material properties. Here, we show that a tunable breaking and forming of a diatomic bond can be achieved through physical means, i.e., by a moderate biaxial strain, in the newly discovered MoN2 two-dimensional (2D) material. On the basis of first-principles calculations, we predict that as the lattice parameter is increased under strain, there exists an isostructural phase transition at which the N-N distance has a sudden drop, corresponding to the transition from a N-N nonbonding state to a N-N single bond state. Remarkably, the bonding change also induces a magnetic phase transition, during which the magnetic moments transfer from the N(2p) sublattice to the Mo(4d) sublattice; meanwhile, the type of magnetic coupling is changed from ferromagnetic to antiferromagnetic. We provide a physical picture for understanding these striking effects. The discovery is not only of great scientific interest in exploring unusual phase transitions in low-dimensional systems, but it also reveals the great potential of the 2D MoN2 material in the nanoscale mechanical, electronic, and spintronic applications.

show abstract

First-order phase transitions in EuCo2P2 and SrNi

Cited by 63 publications

References 15 publications

Lattice collapse and quenching of magnetism inCaFe2As2under pressure: A single-crystal neutron and x-ray diffraction investigation

Lattice collapse and quenching of magnetism inCaFe2As2under pressure: A single-crystal neutron and x-ray diffraction investigation

Superconductivity and the effects of pressure and structure in single-crystallineSrNi2P2

Strain-Induced Isostructural and Magnetic Phase Transitions in Monolayer MoN₂

Contact Info

Product

Resources

About

First-order phase transitions in EuCo2P2 and SrNi

Cited by 63 publications

References 15 publications

Lattice collapse and quenching of magnetism inCaFe2As2under pressure: A single-crystal neutron and x-ray diffraction investigation

Lattice collapse and quenching of magnetism inCaFe2As2under pressure: A single-crystal neutron and x-ray diffraction investigation

Superconductivity and the effects of pressure and structure in single-crystallineSrNi2P2

Strain-Induced Isostructural and Magnetic Phase Transitions in Monolayer MoN2

Contact Info

Product

Resources

About

Strain-Induced Isostructural and Magnetic Phase Transitions in Monolayer MoN₂