| 1. |
- Elson, Frank, et al.
(författare)
-
TRIM Simulations Tool for μ + Stopping Fraction in Hydrostatic Pressure Cells
- 2023
-
Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 2462:1
-
Konferensbidrag (refereegranskat)abstract
- For quantum systems or materials, a common procedure for probing their behaviour is to tune electronic/magnetic properties using external parameters, e.g. temperature, magnetic field or pressure. Pressure application as an external stimuli is a widely used tool, where the sample in question is inserted into a pressure cell providing a hydrostatic pressure condition. Such device causes some practical problems when using in Muon Spin Rotation/Relaxation (μ +SR) experiments as a large proportion of the muons will be implanted in the pressure cell rather than in the sample, resulting in a higher background signal. This issue gets further amplified when the temperature dependent response from the sample is much smaller than that of the pressure cell,which may cause the sample response to be lost in the background and cause difficulties in aligning the sample within the beam. To tackle this issue, we have used pySRIM [1] to construct a practical and helpful simulation tool for calculating muon stopping fractions, specifically for the pressure cell setup at the μE1 beamline using the GPD spectrometer at the Paul Scherrer Institute, with the use of TRIM simulations. The program is used to estimate the number of muon stopping in both the sample and the pressure cell at a given momentum. The simultion tool is programmed into a GUI, making it accessible to user to approximate prior to their experiments at GPD what fractions will belong to the sample and the pressure cell in their fitting procedure.
|
|
| 2. |
- Miniotaite, Ugne, et al.
(författare)
-
Magnetic Properties of Multifunctional 7 LiFePO 4 under Hydrostatic Pressure
- 2023
-
Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 2462:1
-
Konferensbidrag (refereegranskat)abstract
- LiFePO4 (LFPO) is an archetypical and well-known cathode material for rechargeable Li-ion batteries. However, its quasi-one-dimensional (Q1D) structure along with the Fe ions, LFPO also displays interesting low-temperature magnetic properties. Our team has previously utilized the muon spin rotation (μ +SR) technique to investigate both magnetic spin order as well as Li-ion diffusion in LFPO. In this initial study we extend our investigation and make use of high-pressure μ +SR to investigate effects on the low-T magnetic order. Contrary to theoretical predictions we find that the magnetic ordering temperature as well as the ordered magnetic moment increase at high pressure (compressive strain).
|
|
| 3. |
- Miniotaite, Ugne, et al.
(författare)
-
Magnetic Properties of Multifunctional (LiFePO4)-Li-7 under Hydrostatic Pressure
- 2023
-
Ingår i: Proceedings 15th International Conference on Muon Spin Rotation, Relaxation and Resonance (SR). - : IOP Publishing.
-
Konferensbidrag (refereegranskat)abstract
- LiFePO4 (LFPO) is an archetypical and well-known cathode material for rechargeable Li-ion batteries. However, its quasi-one-dimensional (Q1D) structure along with the Fe ions, LFPO also displays interesting low-temperature magnetic properties. Our team has previously utilized the muon spin rotation (mu+SR) technique to investigate both magnetic spin order as well as Li-ion diffusion in LFPO. In this initial study we extend our investigation and make use of high-pressure mu+SR to investigate effects on the low-T magnetic order. Contrary to theoretical predictions we find that the magnetic ordering temperature as well as the ordered magnetic moment increase at high pressure (compressive strain).
|
|
| 4. |
- Nocerino, E., et al.
(författare)
-
Magnetic nature of wolframite MgReO 4
- 2023
-
Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 2462:1
-
Konferensbidrag (refereegranskat)abstract
- Rhenium oxides belonging to the family AReO4 where A is a metal cation, exhibit interesting electronic and magnetic properties. In this study we have utilized the muon spin rotation/relaxation (μ +SR) technique to study the magnetic properties of the MgReO4 compound. To the best of our knowledge, this is the first investigation reported on this interesting material, that is stabilized in a wolframite crystal structure using a special high-pressure synthesis technique. Bulk magnetic studies show the onset of an antiferromagnetic (AF) long range order, or a possible singlet spin state at T C1 ≈ 90 K, with a subtle second high-temperature transition at T C2 ≈ 280 K. Both transitions are also confirmed by heat capacity (Cp ) measurements. From our μ +SR measurements, it is clear that the sample enters an AF order below T C1 = T N ≈ 85 K. We find no evidence of magnetic signal above T N, which indicates that T C2 is likely linked to a structural transition. Further, via sensitive zero field (ZF) μ +SR measurements we find evidence of a spin reorientation at T Cant ≈ 65 K. This points towards a transition from a collinear AF into a canted AF order at low temperature, which is proposed to be driven by competing magnetic interactions.
|
|
| 5. |
|
|
| 6. |
- Nocerino, Elisabetta, et al.
(författare)
-
Magnetic nature of wolframite MgReO4
- 2023
-
Ingår i: 15th International Conference on Muon Spin Rotation, Relaxation and Resonance, MuSR 2022. - : IOP Publishing.
-
Konferensbidrag (refereegranskat)abstract
- Rhenium oxides belonging to the family AReO4 where A is a metal cation, exhibit interesting electronic and magnetic properties. In this study we have utilized the muon spin rotation/relaxation (mu+SR) technique to study the magnetic properties of the MgReO4 compound. To the best of our knowledge, this is the first investigation reported on this interesting material, that is stabilized in a wolframite crystal structure using a special highpressure synthesis technique. Bulk magnetic studies show the onset of an antiferromagnetic (AF) long range order, or a possible singlet spin state at T-C1 approximate to 90 K, with a subtle second hightemperature transition at T-C2 approximate to 280 K. Both transitions are also confirmed by heat capacity (Cp) measurements. From our mu+SR measurements, it is clear that the sample enters an AF order below T-C1 = T-N approximate to 85 K. We find no evidence of magnetic signal above TN, which indicates that T-C2 is likely linked to a structural transition. Further, via sensitive zero field (ZF) mu(+) SR measurements we find evidence of a spin reorientation at T-Cant approximate to 65 K. This points towards a transition from a collinear AF into a canted AF order at low temperature, which is proposed to be driven by competing magnetic interactions.
|
|
| 7. |
- Umegaki, Izumi, et al.
(författare)
-
Magnetic phase diagram of Eu 1- x Ca x Co 2 P 2 determined using muon spin rotation and relaxation
- 2024
-
Ingår i: Physical Review B. - : American Physical Society (APS). - 2469-9950 .- 2469-9969. ; 109:14
-
Tidskriftsartikel (refereegranskat)abstract
- The present study investigated the magnetic nature of a solid solution system consisting of EuCo2P2 and CaCo2P2 using a muon spin rotation and relaxation (mu +SR) technique, which is sensitive to local magnetic environments. The former compound EuCo2P2 is known to enter an incommensurate helical antiferromagnetic (AF) phase below 66 K with neutrons, which was confirmed by the present mu +SR. The magnitude of the ordered Eu moments proposed with neutrons was found to be consistent with that estimated by mu +SR. Furthermore, the latter lattice-collapsed tetragonal phase compound CaCo2P2 is known to enter an A-type AF phase below 90 K, and mu +SR measurements on single crystals revealed the presence of a spin reorientation transition at around 40 K, below which the A-type AF order is likely to be completed. Although all Eu1-xCaxCo2P2 compounds were found to enter a magnetic phase at low temperatures regardless of x, a static ordered state was formed only at the vicinity of the two end compounds, i.e., 0 x 0.4 and 0.9 x 1. Instead, a disordered state, i.e., a random spin-glass state, short-range ordered state, or highly fluctuating state was found in the x range between 0.4 and 0.9, even at the lowest measured temperature (2 K). Together with the magnetization data, our findings clarified the magnetic phase diagram of Eu1-xCaxCo2P2, where a ferromagnetic exchange interaction between Co ions through the Eu2+ ion competes with a direct AF interaction among the Co ions, particularly in the x range between 0.57 and 0.9. This competition yielded multiple phases in Eu1-xCaxCo2P2.
|
|
| 8. |
- Umegaki, Izumi, et al.
(författare)
-
Magnetic phase diagram of Eu1−?Ca?Co2P2 determined using muon spin rotation and relaxation
- 2024
-
Ingår i: Physical Review B. - : American Physical Society. - 2469-9950 .- 2469-9969. ; 109:14
-
Tidskriftsartikel (refereegranskat)abstract
- The present study investigated the magnetic nature of a solid solution system consisting of EuCo2P2 and CaCo2P2 using a muon spin rotation and relaxation (?+SR) technique, which is sensitive to local magnetic environments. The former compound EuCo2P2 is known to enter an incommensurate helical antiferromagnetic (AF) phase below 66 K with neutrons, which was confirmed by the present ?+SR. The magnitude of the ordered Eu moments proposed with neutrons was found to be consistent with that estimated by ?+SR. Furthermore, the latter lattice-collapsed tetragonal phase compound CaCo2P2 is known to enter an ?-type AF phase below 90 K, and ?+SR measurements on single crystals revealed the presence of a spin reorientation transition at around 40 K, below which the ?-type AF order is likely to be completed. Although all Eu1−?Ca?Co2P2 compounds were found to enter a magnetic phase at low temperatures regardless of ?, a static ordered state was formed only at the vicinity of the two end compounds, i.e., 0≤?≤0.4 and 0.9≤?≤1. Instead, a disordered state, i.e., a random spin-glass state, short-range ordered state, or highly fluctuating state was found in the ? range between 0.4 and 0.9, even at the lowest measured temperature (2 K). Together with the magnetization data, our findings clarified the magnetic phase diagram of Eu1−?Ca?Co2P2, where a ferromagnetic exchange interaction between Co ions through the Eu2+ ion competes with a direct AF interaction among the Co ions, particularly in the ? range between 0.57 and 0.9. This competition yielded multiple phases in Eu1−?Ca?Co2P2.
|
|
