transition in CoS2 at high pressures F.S. Elkin, 1 I.P. Zibrov, 1 - PowerPoint PPT Presentation

Thermodynamics of the ferromagnetic phase transition in CoS2 at high pressures F.S. Elkin, 1 I.P. Zibrov, 1 A.P. Novikov, 1 S.S. Khasanov, 2 .A.Sidorov, 1 A.E. Petrova, 1 T.A. Lograsso, 3 J.D. Thompson, 4 and S.M. Stishov 1 1 Institute for High Pressure Physics of Russian Academy of Sciences, Troitsk, Russia 2 Institute for Solid State Physics, Russian Academy of Sciences, Chernogolovka, Moscow Region, Russia 3 Ames Laboratory, Iowa State University, Ames, IA 50011, USA 4 Los Alamos National Laboratory, Los Alamos, NM 87545, USA

0.8 120 Transition temperature T c (K) 0.7 100 100 0.6 80  (  cm)  0.5 60 80  /  (T c ) 40 0.4 60 20 0.3 0 0 50 100 150 40 Temperature (K) 0.2 Pa-3 (205) - cubic prospected 20 0.1 measurements a=5.5385 Å 0.0 0 V=169.89 Å 3 0 1 2 3 4 5 Pressure (GPa) PHYSICAL REVIEW B 83, 060412(R) (2011) High-pressure study of the phase transition in the itinerant ferromagnet CoS2 V. A. Sidorov, V. N. Krasnorussky, A. E. Petrova, A. N. Utyuzh, W. M. Yuhasz, T. A. Lograsso, J. D. Thompson, and S. M. Stishov

Beamline 16-BM-D: Sector 16 - Bending Magnet Beamline HP-CAT Source Bending Materials Science, GeoScience, Chemistry, Physics Magnet Description Monochromator Si(111) This beamline supports high-pressure angle dispersive x-ray diffraction and absorption spectroscopy with microfocus beams. Type Energy Range 6-70 keV Supported Techniques Powder angular dispersive x-ray diffraction 1 x 10 -4 Resolution X-ray absorption near-edge structure ( Δ E/E) Single-crystal diffraction High-pressure diamond anvil cell Flux 5 x 10 8 @30 Beamline Controls and Data Acquisition Windows XP and Linux workstations; EPICS based applications (photons/sec) keV on VME-based electronics. Beam Size Display and control: MEDM, Java, and IDL based software. Detectors (HxV) MAR 345 5µm x 10µm Ge solid state detectors Focused Additional Equipment Unfocused 0.5mm x 0.5mm Cryostats Membrane Control system On-line Ruby system On-line Raman system

Mao-type symmetrical DAC

Beamline 16-BM-D: Sector 16 - Bending Magnet Beamline HP-CAT

Beamline 16-BM-D: Sector 16 - Bending Magnet Beamline HP-CAT

Beamline 16-BM-D: Sector 16 - Bending Magnet Beamline HP-CAT

Beamline 16-BM-D: Sector 16 - Bending Magnet Beamline HP-CAT  = 0.354300 Å

Beamline 16-BM-D: Sector 16 - Bending Magnet Beamline HP-CAT  = 0.424603 Å

Phase diagram of CoS2 at high pressure Curve 1 was determined making use a ”lead” manometer to measure pressure 12 . Curve 2 was determined by X-ray diffraction and the pressure measured by a ruby sensor.

AC-calorimetry experinents 7 T C CoS 2 6 5 T G GW60/40 2 ) 4 C/T (  J/K 3 2 1 1.22 GPa 0 0 50 100 150 200 250 300 T(K)

Entropy of the phase transition in CoS2

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