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 HellmanDepartment of Physics, University of California, Berkeley

Alexandra Navrotsky, Maria Dorogova, Charles E. LesherThermochemistry Facility and Dept. of Geology, University of California, Davis

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Constituents of Mantle• Primarily silicates• Fe,Mg majority of composites• Al,Ni,Ca,Cd,Co minority “dopants”• High pressure and high temperature

yields complicated phase diagramof novel crystal structures– Spinel (γ)– Modified Spinel (β)– Perovskite– Post-perovskite

Navrotsky. Prog. Solid St. Chem. 17, 53-86 (1987).

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Fe v. Mg Silicates

Hazen, R. Science 259, 206-9 (1993).

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

“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 Keithley

Instrumentation Award

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Device Simulation

0.0 0.1 0.2 0.3 0.4 0.5

0.00

0.05

0.10

0.15

0.20

0.25

Tem

pera

ture

(K

)

Time (s)

0.0 0.1 0.2 0.3 0.4 0.54.53999E-5

1.2341E-4

3.35463E-4

9.11882E-4

0.00248

0.00674

0.01832

0.04979

0.13534

0.36788

Te

mp

era

ture

(K

)

Time (s)

Chi^2/DoF 3.17328E-8R^2 0.99999

Parameter Value Error---------------------------------------------y0 4.54671E-5 1.98301E-5A1 0.22375 7.30476E-5t1 0.06524 3.81133E-5

0.0 0.1 0.2 0.3 0.4 0.5

0.00

0.05

0.10

0.15

0.20

0.25

Tem

pera

ture

(K)

Time (s)

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Device Simulation

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Proof of Principle

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Proof of Principle

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

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

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

COMPRES Proposal

• Used indium in past– Low melting point, but not good

for metastable materials

• Silver paint– Reproducibility?

• Multi-anvil and/or diamond-anvil cell experiments– Thermal contact– Sample size– Crystal shape

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

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

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

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

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

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?

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Fe2SiO4 Spinel

K. Suito et al. Proc. 9th AIRAPT Intl. High P. Conference. 295-8 (1983).

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Fe2SiO4 Spinel

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Fe2SiO4 Spinel

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

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

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

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

COMPRES Calorimetry on a Chip Workshop – March 15, 2007

University of California at Berkeley – Physics Department – Hellman Lab

Thanks to:

Frances HellmanAlex NavrostskyMasha DorogovaCharles Lesher

Department of Energy

Lawrence Berkeley National LabUniversity of California – BerkeleyUniversity of California – DavisOak Ridge National Laboratory

Ray JeanlozDaniel QueenErik Helgren

COMPRES Calorimetry on a Chip Workshop – March 15, 2007