Publications of our lab members


2023 and papers in press

[52] Ohta, K., Suehiro, S., Kawaguchi, S., Okuda, Y., Wakamatsu, T., Hirose, K., Ohishi, Y., Kodama, M., Hirai, S., & Azuma, S. Measuring the electrical resistivity of liquid iron to 1.4 Mbar. Physical Review Letters, 130, 266301.


[51] Nagaya, Y., Gomi, H., Ohta, K., & Hirose, K. Equations of state for B2 and bcc Fe1-xSix. Physics of Earth and Planetary Interiors, 341, 107046.


[50] Ohta, K. Ammonia and the ice giants. Nature Physics, https://doi.org/10.1038/s41567-023-02081-9.


[49] Park, Y., Yonemitsu, K., Hirose, K., Kuwayama, Y., Azuma, S., & Ohta, K. Viscosity of Earth’s inner core constrained by Fe-Ni interdiffusion in Fe-Si alloy in an internal-resistive-heated diamond anvil cell. American Mineralogist, 108, 1064–1071.


[48] Okuda, Y & Ohta, K. Heat flow from the Earth's core inferred from experimentally determined thermal conductivity of the deep lower mantle. Core-mantle Co-evolution: An interdisciplinary approarch, AGU monograph, 133–144..


[47] Hasegawa, A., Ohta, K., Yagi, T., & Hirose, K. Thermal conductivity of platinum and periclase under extreme conditions of pressure and temperature. High Pressure Research, https://doi.org/10.1080/08957959.2023.2193892.


2022

[46] Okuda, Y., Oka, K., Kubota, Y., Inada, M., Kurita, N., Ohta, K., & Hirose, K. High P-T impedance measurements using a laser-heated diamond anvil cell. Review of Scientific Instruments, 93, 105103.


[45] Wakamatsu, T., Ohta, K., Tagawa, S., Yagi, T., Hirose, K., & Ohishi, Y. Compressional wave velocity for iron hydrides to 100 gigapascals. Physics and Chemistry of Minerals, 49, 17, https://doi.org/10.1007/s00269-022-01192-8.


[44] Aoyama, T., Ohta, K., Shimizu, K., & Ohgushi, K. Persistent spin-orbit Mott insulating state in highly compressed post-perovskite CaIrO3. Journal of the Physical Society of Japan, 91, 045003. https://doi.org/10.7566/JPSJ.91.045003


2021

[43]

Zhang, Z., Zhang, D.B., Onga, K., Hasegawa, A., Ohta, K., Hirose, K., & Wentzcovitch, R.

Thermal conductivity of CaSiO3 perovskite at lower mantle conditions

Physical Review B, 104, 184101. https://doi.org/10.1103/PhysRevB.104.184101


[42]

Sakuraba, S., Kurokawa, H., Genda, H., & Ohta, K.

Numerous chondritic impactors and oxidized magma ocean set Earth’s volatile depletion

Scientific Reports, 11, 20894. https://doi.org/10.1038/s41598-021-99240-w


[41]

Okuda, Y., Ohta, K., Nishihara, Y., Hirao, N., Wakamatsu, T., Suehiro, S., Kawaguchi, S., & Ohishi, Y.

Low-spin ferric iron in primordial bridgmanite crystallized from a deep magma ocean

Scientific Reports, 11, 19471. https://doi.org/10.1038/s41598-021-98991-w


[40]

Ohta, K., & Hirose, K.

The thermal conductivity of the Earth's core and implications for its therma and compositional evolution

National Science Review, 8, nwaa303. https://doi.org/10.1093/nsr/nwaa303


[39]

Okuda, Y., Kimura, S., Ohta, K., Park, Y., Wakamatsu, T., Mashino, I., & Hirose, K.

A cylindrical SiC heater for an externally heated diamond anvil cell to 1500 K

Review of Scientific Instruments, 92, 015119. https://doi.org/10.1063/5.0036551


2020

[38]

Ohta, K., Wakamatsu, T., Kodama, M., Kawamura, K., & Hirai, S.

Laboratory-based X-ray computed tomography for 3D imaging of samples in a diamond anvil cell in situ at high pressures

Review of Scientific Instruments, 91, 093703 (2020). https://doi.org/10.1063/5.0014486


[37]

Okuda, Y., Ohta, K., Sinmyo, R., Hirose, K., & Ohishi, Y.

Anomarous compressibility in (Fe,Al)-bearing bridgmanite: implications for the spin state of iron

Physics and Chemistry of Minerals, 47, 40 (2020). https://doi.org/10.1007/s00269-020-01109-3


[36]

Okuda, Y., Ohta, K., Hasegawa, A., Yagi, T., Hirose, K., Kawaguchi, S. I., & Ohishi, Y.

Thermal conductivity of Fe-bearing post-perovskite in the Earth's lowermost mantle

Earth and Planetary Science Letters, 547, 116466 (2020). https://doi.org/10.1016/j.epsl.2020.116466


[35]

Inoue, H., Suehiro, S., Ohta, K., Hirose, K., & Ohishi, Y.

Resistivity saturation of hcp Fe-Si alloys in an internally heated diamond anvil cell: A key to assessing the Earth's core conductivity

Earth and Planetary Science Letters 543, 116357 (2020). https://doi.org/10.1016/j.epsl.2020.116357


[34]

Kato, C., Umemoto, K., Ohta, K., Tagawa, S., Hirose, K., & Ohishi, Y.

Stability of fcc phase FeH to 137 GPa

American Mineralogist 105, 917-921 (2020). DOI: https://doi.org/10.2138/am-2020-7153


2019

[33]

Suehiro, S., Wakamatsu, T., Ohta, K., Hirose, K., & Ohishi, Y.

High-temperature electrical resistivity measurements of hcp iron to Mbar pressure in an internally resistive heated diamond anvil cell

High Pressure Research 39, 579-587 (2019). https://doi.org/10.1080/08957959.2019.1692008


[32]

Matsuoka, T., Muraoka, S., Ishikawa, T., Niwa, K., Ohta, K., Hirao, N., Kawaguchi, S., Ohishi, Y., Shimizu, K., & Sasaki, S.

Hydrogen-storing salt NaCl(H2) synthesized at high pressure and high temperature

The Journal of Physical Chemistry C 123, 25074-25080 (2019). https://doi.org/10.1021/acs.jpcc.9b06639


[31]

Hasegawa, A., Yagi, T., & Ohta, K.

Combination of pulsed light heating thermoreflectance and laser-heated diamond anvil cell for in-situ pressure-temperature thermal diffusivity measurements

Review of Scientific Instrum 90, 074901 (2019). https://doi.org/10.1063/1.5093343


[30]

Okuda, Y., Ohta, K., Sinmyo, R., Hirose, K., Yagi, T, & Ohishi, Y.

Effect of spin transition of iron on the thermal conductivity of (Fe,Al)-bearing bridgmanite

Earth and Planetary Science Letters 520, 188-198 (2019). https://doi.org/10.1016/j.epsl.2019.05.042


[29]

Hasegawa, A., Ohta, K., Yagi, T., Hirose, K., Okuda, Y., & Kondo, T.

Composition and pressure dependence of lattice thermal conductivity of (Mg,Fe)O solid solutions

Comptes Rendus Geoscience 351, 229-235 (2019). https://doi.org/10.1016/j.crte.2018.10.005

[28]

Ohta, K., Suehiro, S., Hirose, K., & Ohishi, Y.

Electrical resistivity of fcc phase iron hydrides at high pressures and temperatures

Comptes Rendus Geoscience 351, 147-153 (2019). https://doi.org/10.1016/j.crte.2018.05.004


2018

[27]

Ohta, K., Nishihara, Y., Sato, Y., Hirose, K., Yagi, T., Kawaguchi, S., Hirao, N., & Ohishi Y.

An experimental examinaion of thermal conductivity anisotropy in hcp iron

Frontiers in Earth Science 6, 176 (2018). https://doi.org/10.3389/feart.2018.00176


[26]

Wakamatsu, T., Ohta, K., Yagi, T., Hirose, K., & Ohishi, Y.

Measurements of sound velocity in iron-nickel alloys by femtosecond laser pulses in a diamond anvil cell

Physics and Chemistry of Minerals 45, 589-595, (2018). https://doi.org/10.1007/s00269-018-0944-3


2017

[25]

Suehiro, S., Ohta, K., Hirose, K., Morard, G., & Ohishi Y.

The influence of sulfur on the electrical resistivity of hcp iron: implications for the core conductivity of Mars and Earth

Geophysical Research Letters 44, 8254-8259 (2017). https://doi.org/10.1002/2017GL074021


[24]

Matsuoka, T., Kuno, K., Ohta, K., Sakata, M., Nakamoto, Y., Hirao, N., Ohishi, Y., Shimizu, K., Kume, T., & Sasaki, S.

Lithium polyhydrides synthesized under high pressure and high temperature

Journal of Raman Spectroscopy 48, 1222-1228 (2017). https://doi.org/10.1002/jrs.5183


[23]

Okuda, Y., Ohta, K., Yagi, T., Sinmyo, R., Wakamatsu, T., Hirose, K., & Ohishi, Y.

The effect of iron and aluminum incorporation on lattice thermal conductivity of bridgmanite at the Earth's lower mantle

Earth and Planetary Science Letters 474, 25-31 (2017). https://doi.org/10.1016/j.epsl.2017.06.022


[22]

Ohta, K., Yagi, T., Hirose, K., & Ohishi, Y.

Thermal conducitivity of ferropericlase in the Earth's lower mantle

Earth and Planetary Science Letters 465, 29-37 (2017). https://doi.org/10.1016/j.epsl.2017.02.030

2016

[21]

Ohta, K., Kuwayama, Y., Hirose, K., Shimizu, K., & Ohishi, Y.

Experimental determination of the electrical resistivity of iron at Earth's core conditions

Nature 534, 95-98 (2016). https://doi.org/10.1038/nature17957


[20]

Tagawa, S., Ohta, K., Hirose, K., Kato, C., & Ohishi, Y.

Compression of Fe-Si-H alloys to core pressures

Geophysical Research Letters 43, 3686-3692 (2016). https://doi.org/10.1002/2016GL068848


2015

[19]

Ohta, K., Ichimaru, K., Einaga, M., Kawaguchi, S., Shimizu, K., Matsuoka, T., Hirao, N., & Ohishi, Y.

Phase boundary of hot dense fluid hydrogen

Scientific Reports, 5, 16560, doi:10.1038/srep16560.

[Article link] [Press release. Tokyo Tech] [Press release, SPring-8]


[18]

Kuno, K., Matsuoka, T., Nakagawa, T., Hirao, N., Ohishi, Y., Shimizu, K., Takahama, K., Ohta, K., Sakata, M., Nakamoto, Y., Kume, T., Sasaki, S.

A laser heating of Li in hydrogen: Possible synthesis of LiHx

High Pressure Research, 35, 16-21, DOI:10.1080/08957959.2014.999677.

[Article]



2014

[17]

Imada, S., Ohta, K., Yagi, T., Hirose, K., Yoshida, H., and Nagahara, H.

Measurements of lattice thermal conductivity of MgO to core-mantle boundary pressures

Geophysical Research Letters, 41, doi:10.1002/2014GL060423.

[Article]


[16]

Ohta, K., Fujino, K., Kuwayama, Y., Kondo, T., Shimizu, K., and Ohishi, Y.

Highly conductive iron-rich (Mg,Fe)O magnesiowüstite and its stability in the Earth’s lower mantle

Journal of Geophysical Research, Solid Earth, 119, DOI: 10.1002/2014JB010972.

[Article]


[15]

Matsuoka, T., Sakata, M., Nakamoto, Y., Takahama, K., Ichimaru, K., Mukai, K., Ohta, K., Hirao, N., Ohishi, Y., and Shimizu, K.

Pressure-induced re-entrant metallic phase of lithium

Physical Review B, 89, 144103.

[Article] [Press release]


[14]

Ohta, K., Yagi, T., and Hirose, K.

Thermal diffusivities of MgSiO3 and Al-bearing MgSiO3 perovskites

American Mineralogist, 99, 94-97.

[Article]



2013

[13]

Gomi, H., Ohta, K., Hirose, K., Labrosse, S., Caracas, R., Verstraete, M. J., Hernlund, J. W.

The high conductivity of iron and thermal evolution of the Earth’s core

Physics of the Earth and Planetary Interiors, 224, 88-103.

[Article]



2012

[12]

Sugimura, E., Komabayashi, T., Ohta, K., Hirose, K., Ohishi, Y., and Dubrovinsky, L.

Experimental evidence of superionic conduction in H2O ice

Journal of Chemical Physics, 137, 194505.

[Article]


[11]

Ohta, K., Yagi, T., Taketoshi, N., Hirose, K., Komabayashi, T., Baba, T., Ohishi, Y., and Hernlund, J.

Lattice thermal conductivity of MgSiO3 perovskite and post-perovskite at the core-mantle boundary

Earth and Planetary Science Letters, 349-350, 109-115.

[Article]


[10]

Ohta, K., Cohen, R. E., Hirose, K., Haule, K., Shimizu, K., and Ohishi, Y.

Experimental and theoretical evidence for pressure-induced metallization in FeO with the rock-salt type structure

Physical Review Letters, 108, 026403

[Article], [Press release]



2011

[9]

Ozawa, H., Hirose, K., Ohta, K., Ishii, H., Hiaoka, N., Ohishi, Y., and Seto, Y

Spin crossover, structural change, and metallization in NiAs-type FeO at high pressure

Physical Review B, 84, 134417

[Article]


[8]

Yagi, T., Ohta, K., Kobayashi, K., Taketoshi, N., Hirose, K., and Baba, T

Thermal diffusivity measurement in diamond anvil cell using light pulse thermoreflectance technique

Measurement Science and Technology, 22, 024011

[Article]




2010

[7]

Iizuka, T., McCulloch, M.T., Komiya, T., Shibuya, T., Ohta, K., Ozawa, H., Sugimura, E., and Collerson, K.D.

Monazite geochronology and geochemistry of meta-sediments in the Narryer Gneiss Complex, Western Australia: constraints on the tectonothermal history and provenance

Contributions to Mineralogy and Petrology, 160, 803-823

[Article]


[6]

Ohta, K., Hirose, K., Shimizu, K., and Ohishi, Y.

High-pressure experimental evidence for metal FeO with normal NiAs-type structure

Physical Review B, 82, 174120

[Article]


[5]

Ohta, K., Hirose, K., Shimizu, K., Sata, N., and Ohishi, Y.

The electrical resistance measurements of (Mg,Fe)SiO3 perovskite at high pressures and implications for electronic spin transition of iron

Physics of the Earth and Planetary Interiors, 180, 154-158

[Article]


[4]

Ohta, K., Hirose, K., Ichiki, M., Shimizu, K., Sata, N., and Ohishi, Y.

Electrical conductivities of pyrolitic mantle and MORB materials up to the lowermost mantle conditions

Earth and Planetary Science Letters, 289, 497-502

[Article]




2008

[3]

Ohta, K., Onoda, S., Hirose, K., Sinmyo, R., Shimizu, K., Sata, N., Ohishi, Y., and Yasuhara, A.

The electrical conductivity of post-perovskite in Earth’s D” layer

Science, 320, 89-91

[Article]


[2]

Ohta, K., Hirose, K., Lay, T., Sata, N., and Ohishi, Y.

Phase transitions in pyrolite and MORB at lowermost mantle conditions: Implications for a MORB-rich pile above the core-mantle boundary

Earth and Planetary Science Letters, 267, 107-117

[Article]



2007

[1]

Ohta, K., Hirose, K., Onoda, S., and Shimizu, K.

The effect of iron spin transition on electrical conductivity of (Mg,Fe)O magnesiowüstite

Proceedings of the Japan Academy, Ser. B, 83, 97-100

[Article]