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University of California at Berkeley – Physics Department – Hellman Lab

Application of “Calorimetry-on-a-Chip” Technology to Heat Capacities of Quenched High Pressure Samples. David W. Cooke, Frances Hellman Department of Physics, University of California, Berkeley. Alexandra Navrotsky, Maria Dorogova, Charles E. Lesher

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University of California at Berkeley – Physics Department – Hellman Lab

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  1. Application of “Calorimetry-on-a-Chip” Technology to Heat Capacities of Quenched High Pressure Samples David W. Cooke, Frances Hellman Department of Physics, University of California, Berkeley Alexandra Navrotsky, Maria Dorogova, Charles E. Lesher Thermochemistry Facility and Dept. of Geology, University of California, Davis University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  2. Constituents of Mantle • Primarily silicates • Fe,Mg majority of composites • Al,Ni,Ca,Cd,Co minority “dopants” • High pressure and high temperatureyields complicated phase diagramof novel crystal structures • Spinel (γ) • Modified Spinel (β) • Perovskite • Post-perovskite Navrotsky. Prog. Solid St. Chem.17, 53-86 (1987). University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  3. Fe v. Mg Silicates Hazen, R. Science259, 206-9 (1993). University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  4. “Calorimeter on a Chip” • Specific heat of thin films • 100nm ~= 5µg • 2K - 500K • 0T - 8T • Information gained: • Thermodynamics • Decomposition • Magnetic transitions • Electrical changes 2006 APS KeithleyInstrumentation Award University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  5. Chi^2/DoF 3.17328E-8 R^2 0.99999 Parameter Value Error --------------------------------------------- y0 4.54671E-5 1.98301E-5 A1 0.22375 7.30476E-5 t1 0.06524 3.81133E-5 Device Simulation University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  6. Device Simulation University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  7. Proof of Principle University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  8. Proof of Principle University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  9. COMPRES Proposal • Multi-anvil and/or diamond-anvil cell experiments • Thermal contact • Sample size • Crystal shape • Magnetic transitions in high pressure minerals • Test case – Fe2SiO4 spinel • Data across an Mg-Fe substituted series • (Fe,Mg)2SiO4 olivine and/or spinel phases • (Mg,Fe)O magnesiowustites University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  10. COMPRES Proposal • Multi-anvil and/or diamond-anvil cell experiments • Thermal contact • Sample size • Crystal shape • Used indium in past • Low melting point, but not good for metastable materials • Silver paint • Reproducibility? University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  11. COMPRES Proposal • Multi-anvil and/or diamond-anvil cell experiments • Thermal contact • Sample size • Crystal shape • Sample Size • Data on large devices (CoO) • Addenda (Cu/LSN) = ~50 μJ • Ag Addenda = ~100 μJ • Sample = ~200 μJ • Sample Size • Data on regular devices • Addenda (LSN) = ~3 μJ • Copper Addenda = ~2 μJ • Sample = ~2 μJ University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  12. COMPRES Proposal • Multi-anvil and/or diamond-anvil cell experiments • Thermal contact • Sample size • Crystal shape • Magnetic transitions in high pressure minerals • Test case – Fe2SiO4 spinel • Data across an Mg-Fe substituted series • (Fe,Mg)2SiO4 olivine and/or spinel phases • (Mg,Fe)O magnesiowustites University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  13. Fe2SiO4 Spinel • Why Fe2SiO4 Spinel? • Relatively low pressure of formation (~8GPa) • Larger quantity of sample • Multi-anvil apparatus (Charles Lesher’s lab) • Relevant to mantle physics • Potential Mg/Fe substitutional analysis • Iron silicate – we expect a magnetic transition • Fe2+ v. Fe3+ – potential electronic interactions? University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  14. Fe2SiO4 Spinel K. Suito et al. Proc. 9th AIRAPT Intl. High P. Conference. 295-8 (1983). University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  15. Fe2SiO4 Spinel University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  16. Fe2SiO4 Spinel University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  17. COMPRES Proposal • Multi-anvil and/or diamond-anvil cell experiments • Thermal contact • Sample size • Crystal shape • Magnetic transitions in high pressure minerals • Test case – Fe2SiO4 spinel • Data across an Mg-Fe substituted series • (Fe,Mg)2SiO4 olivine and/or spinel phases • (Mg,Fe)O magnesiowustites University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  18. Future Work • Diamond Anvil Cell Sample Capability • Develop reliable method for ~10μg sample • Consistency of silver paint? • Fe2SiO4 Spinel • Can we factor out the magnetic entropy • Why is the magnetic transition so much more broad? • Substitutional (Fe,Mg)2SiO4 series • Decomposition enthalpy • Other materials of geophysical applications • (Mg,Fe)O magnesiowustites • (Mg,Fe)SiO3 perovskites • High pressure phases in zirconia and titania University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

  19. Thanks to: Frances Hellman Alex Navrostsky Masha Dorogova Charles Lesher Ray Jeanloz Daniel Queen Erik Helgren Department of Energy Lawrence Berkeley National Lab University of California – Berkeley University of California – Davis Oak Ridge National Laboratory University of California at Berkeley – Physics Department – Hellman Lab COMPRES Calorimetry on a Chip Workshop – March 15, 2007

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