Profile
日本語/English
Yusuke Iguchi, Ph.D.
Pronunciation [yoo-sooh-keh ee-gooh-chee]
Contact
Senior Research Scientist-Physical
Geballe Laboratory for Advanced Materials, Stanford University
476
Lomita Mall, McCullough Room 137, Stanford, CA 94305, USA
email: yiguchi(at)stanford.edu
Education
PhD & MS, Department of Basic Science, The University of Tokyo, Tokyo (2018) (Advisor: Yoshinori Onose)
Teaching certificate for Science in middle & high schools, Tokyo University of Science (2013)
BS, Department of Physics, Tokyo University of Science, Tokyo (2013) (Advisor: Setsuo Mitsuda)
Employment history/work experience
2020 - current Senior Research Scientist-Physical, Geballe Laboratory for Advanced Materials,
Stanford University
2018 - 2020 Postdoctoral Research Fellow, Department of Applied Physics, Stanford University
(Advisor: Kathryn Ann Moler)
2018 - 2020 Japan Society for the Promotion of Science Overseas Research Fellow
2016 - 2018 Research Fellow (DC2) of Japan Society for the Promotion of Science
Honors and Awards
2018/4 Overseas Research Fellowship of Japan Society for the Promotion of Science
2017/1 Journal of Physical Society of Japan Papers of Editors' Choice
2016/4 Research Fellowship (DC2) of Japan Society for the Promotion of Science
2015/3 Outstanding Graduate Student Award, Graduate School of Arts and Sciences, University of Tokyo
2024/5 UJA Outstanding Paper Award
Selected Papers (All papers are here, all talks are here)
Superconducting vortices carrying a temperature-dependent fraction of the flux quantum
Y. Iguchi, R.A. Shi, K. Kihou, C.-H. Lee, M. Barkman, A. L. Benfenati, V. Grinenko, E. Babaev, and K. A. Moler
Science 380, 1244-1247 (2023).Microscopic imaging homogeneous and single phase superfluid density in UTe$_2$
Y. Iguchi, H. Man, S. M. Thomas, F. Ronning, P.F.S. Rosa, and K. A. Moler
Physical Review Letters 130, 196003 (2023)Local observation of linear-T superfluid density and anomalous vortex dynamics in URu$_2$Si$_2$
Y. Iguchi, I. P. Zhang, E. D. Bauer, F. Ronning, J. R. Kirtley, K. A. Moler
Physical Review B (Letter) 103, L220503 (2021)Microwave non-reciprocity of magnon excitations in a non-centrosymmetric antiferromagnet Ba$_2$MnGe$_2$O$_7$
Y. Iguchi, Y. Nii, M. Kawano, H. Murakawa, N. Hanasaki, and Y. Onose
Physical Review B 98, 064416 (2018)- Magnetoelectrical control of nonreciprocal microwave response in a multiferroic helimagnet
Y. Iguchi, Y. Nii, and Y. Onose
Nature Communications 8, 15252 (2017) Nonreciprocal magnon propagation in a noncentrosymmetric ferromagnet LiFe$_5$O$_8$
Y. Iguchi, S. Uemura, K. Ueno, and Y. Onose
Physical Review B 92, 184419 (2015)
Teaching Experience
2022/7-current Girls Who Code in Japanese, Teacher,
Japan
2022/5 nano@stanford,
Guest Teacher at Greenleaf TK-8 School, CA
2021/12 Skype a Scientist,
Guest Teacher at Chardon Primary School, NE
2013-2014 Material Science
Exp. II/III, University of Tokyo, Japan, Teaching Assistant
Summer
2012 Physics I, Guest
Teacher at Kumagaya High School, Japan
Professional and Leadership Activities
2022/7-current Co-Founder & Organizer, Girls Who Code in Japanese, Japan2022/6-current Co-Founder & Organizer, Japanese Academic Seminars at Stanford, Stanford, CA
2024/3 Session chair, American Physical Society March Meeting 2024(Minneapolis), D16
2023/12 Speaker, "Unleashing Children's Potential: How to Raise Kids Who Love Math!",
ECC public webinar
2023/11 Panelist, "The Interaction Crisis:
Reshaping Synchronous Online Education,"
SpatialChat public webinar
2023/9 Panelist, "Network Enhancement for
Overseas Japanese Research Community,"
1st UJA General Meeting,
Consulate-General of Japan in Boston
2023/9 Organizer, "The overseas career for Women researchers," 1st JASS&SA Webinar
2023/9 Session chair, 78th Ann. Meeting, The Physical Society of Japan, Sendai, Japan
2022/8 Session chair, 29th
Inter. Conf. on Low Temperature Physic (LT29), Sapporo
2020/5-2021/7 Organizer, TED circle at
Bechtel International Center, Stanford University, CA
2019/12 Session chair, 32nd
International Symposium on Superconductivity, Kyoto
Reviewers, Science, npj Quantum
Materials, Scientific Reports, Science Progress
Visiting(short-term)
2019/1, Max Planck Institute for
Chemical Physics of Solids, Dresden, Germany (C. Hicks group)
2018/6, Osaka University, Osaka, Japan (N. Hanasaki group)
2012/11,12, 2013/2, Photon Factory at KEK, Tsukuba, Japan (BL-3A, H. Nakao group)
2012/10, SPring-8, Hyogo, Japan (BL-29XU, Y. Tanaka group)
2012/4, National Institute for Materials Science, Tsukuba, Japan (N. Terada group)
Experimental skills
Measurements
Synchrotron X-Ray diffraction
Microwave spectroscopy(Low temperature
Microwave broadband measurement in magnetic field/Design of
microwave circuit/Micro Fabrication
of Microwave circuit by using Photo- and EB-lithography)
Scanning SQUID
microscopy
Ultra-low
temperature measurement (Cryogenic dilution cryostat, Liquid He3/He4 cryostat)
Uniaxial strain measurement (Mechanical
uniaxial stress/Micro uniaxial
stress by piezo)
Sample
growth
Polycrystal growth
(EB, Spattering, Resistance heating)
Single crystal
growth (Floating zone, Flux)
Others
Programing (Perl,
Python, MATLAB)
Equipment Remote
Control (Lab view, MATLAB, Python)
Radioactive
material treatment (URu$_2$Si$_2$,UTe$_2$)
Area of Specialty
3. Local superconducting states in
unconventional superconductors by using scanning SQUID Microscopy
Senior Research Scientist/Postdoc, Stanford
University (2018-current):
I
am working as a Senior Research Scientist at Stanford University in the Moler group
after I finished my postdoctoral research in 2018-2020. We newly launched the
cryogenic dilution unit (BLUEFORS) and introduced the scanning SQUID
microscope to apply chiral superconductor candidates. We observed local linear-T superfluid density and coexisting ferromagnetic domains with the superconductivity in URu$_2$Si$_2$. [Phys. Rev. B(Letter) 2021] We also microscopically measured the temperature dependence of the superfluid density without any kink below $T_c$ on a newly discovered odd parity superconductor UTe$_2$, suggesting the absence of multiple superconducting phase transitions at ambient pressure and anisotropic gap structures. [Phys. Rev. Lett. 2023] We also reported the absence of any kink in the superfluid density below $T_c$ of Sr$_2$RuO$_4$ under uniaxial strains. [Phys. Rev. B 2023]
We have also studied the statistics and dynamics of superconducting vortices at the dilution fridge and another cryogenic 4K cryostat (BLUEFORS). We observed the anisotropic vortex dynamics in the nematic superconductor FeSe. [Phys. Rev. B 2019] The observed vortex dynamics can be explained by our simulation using the toy model of the quadratic pinning potential. We also observed the isotropic and anisotropic vortex dynamics at different locations of URu$_2$Si$_2$. [Phys. Rev. B(Letter) 2021] We also observed pinned vortices and anti-vortices near zero fields in UTe$_2$, suggesting the existence of hidden internal magnetic fields. [Phys. Rev. Lett. 2023] We also observed the un-quantized vortex in a multiband superconductor K$_{0.77}$Ba$_{0.23}$Fe$_2$As$_2$. [Science 2023]
2. Non-reciprocity
of magnon excitations in non-centrosymmetric magnets
MS & PhD, University of Tokyo (2013-2018):
I
am a first member of Onose Laboratory. We launched the 20 GHz microwave
measurement system and implemented the creation of single crystals, the design
of the microwave antenna, and the micro-fabrication. We first observed the
nonreciprocal microwave response via the asymmetric magnon-band in the chiral
system, which is denoted as the Rashba effect in the magnon system.[Phys. Rev. B 2015] In addition,
in the microwave measurement system, we observed the nonreciprocal propagation
of the surface acoustic wave (SAW) via the phonon-magnon coupling[Phys. Rev. B(Rapid Communications) 2017], and we
electrically and magnetically controlled the nonreciprocal propagation of
microwaves in multiferroics.[Nat. Commun. 2017; J. Phys. Soc. Jpn.2017; Appl. Phys. Lett. 2022] In addition, we also designed the 40 GHz
microwave measurement system. We succeeded in observing the nonreciprocal
microwave propagation in antiferromagnetic multiferroics and quantitatively
evaluating the nonreciprocity.[Phys. Rev. B 2018]
1. Uniaxial-Pressure Effects on Spin-Driven
Lattice Distortions in Geometrically Frustrated Magnets
BS, Tokyo University of Science (2012):
We
revealed that the lattice largely responds to a pressure near the phase
transition point in CuFeO$_2$, which has a strong spin-lattice
correlation, by the measurement of Synchrotron radiation in uniaxial press.[J. Phys. Soc. Jpn. 2013]
Doctoral Dissertation
"Non-reciprocity of magnon excitations in non-centrosymmetric magnets" (doi/10.15083/00077865)