High pressure clamp cells for neutron scattering at low temperatures and high external magnetic fields
Abstract
High pressure clamp cells for neutron scattering studies of condensed matter under applied magnetic field could be made of hard nonmagnetic alloys: TiZr , Al, NiCrAl, CuBe, 40 HNU. These cells are suitable to be used on pulse and reactor neutron sources for powder and single crystal studies, both for diffraction and inelastic neutron scattering. They can be placed in typical cryostats (dilution fridge also) and high magnetic fields. As an example the nonmagnetic cell made of TiZr+40HNU was used for determination of form-factor dependence of magnetic moments in CePd2Si2 under pressures up to 30kbar and H=10T with polarized neutrons on D3-ILL [1]. Some of these cells were used for investigations of magnetic spirals in ZnCr2S4, CsCuCl3 and MnSi [2] under pressure. Single crystal or powder NaCl-a pressure calibrant and Fluorinert- pressure medium [3] were used in experiments on the neutron sources SINQ, ISIS (LT up to 100mk), HMI (H up to 6T), ILL (10T) and SNS. For measuring “in situ” under high pressure compressibility of solid deuterium was made special high pressure cell from TiZr with support from hard steel [4]. High pressure cells (insert NiCrAl and support -Al alloy) also was made for experiments by inelastic neutron scattering [5].
1. Sketch of the high pressure clamp cell(HPC16) for powder neutron diffraction made from zero matrix alloy TiZr ((1,2)and steel support (3).
2. HPC25-100mk PRIZMA-ISIS-UK-2001Quantum melting in magnetic matals CeRh2Si2.
The large bore TiZr + NiCrAl alloys piston cell mounted on the dilution fridge insert. The cell can accept a crystal up to 4,7mm in diameter and operates at pressures up to 2.5GPa at low temperature.
3. Photographs and sketch of the P=40kbar non-magnetic clamp cell used in the 10T cryomagnet on the polarized neutron diffractometer D3.
Magnetic form factors measured in the CePd2Si2 The Spin Polarised Hot Neutron Beam Facility D3(ILL) paramagnetic states:
above 10K at P=0 kbar (blue circles) and at the lowest accessible temperature (1.4 K) at
p » 30 kbar (red circles). Preliminary refinements within the dipolar approximation are shown
as dotted lines.
4. A single-crystal pressure cell for trics up to 3gpa.
Bragg peaks and magnetic satellites from the sample measured with the 2D detector at p=3GPa, T=17K (scans in omega presented as a sequence of 1D projection onto one of the detector axes). Ba-hexaferrite BaFe8.8Co1.6Ti1.6O19.
5.
1. N. Kernavanois, R. Sadykov, E. Ressouche, S. Raymond, P. Lejay and J. Flouquet.
ILL Annual Report 2004/highlights/.
2. B.Fak,R.A.Sadykov, J.Flouquet, G. Lapertot. J. Phys.: Condens.Matter17(2005)1635-1644.
3. V A Sidorov and R A Sadykov. J. Phys.: Condens. Matter 17 (2005) S3005–S3008.
4. Sadykov R.A., Gruzin P.L., Suhoparov V.A. High Pressure Research,Vol.4, pp.99-202, 1995.
5. A. I. Kolesnikov, A. Podlesnyak, R. A. Sadykov, V. E. Antonov, M. A. Kuzovnikov,
G. Ehlers, and G. E. Granroth. Рhysical Review B 94, 134301-5, (2016).