Members

Keshav D​ani

kmdani ('at' oist.jp)

Full Professor
[November 2023 - present]

Associate Professor
[April 2018 - October 2023]

Assistant Professor
[November 2011 - March 2018]

I joined OIST as an Asst. Professor in Nov. 2011 after completing a Director’s Postdoctoral Fellowship at the Center for Integrated Nanotechnologies at Los Alamos National Laboratory. I graduated from UC Berkeley in 2006 with a PhD in Physics under the supervision of Prof. Daniel Chemla. I obtained a BS from Caltech in Mathematics with a senior thesis in Quantum Information Theory under John Preskill and Hideo Mabuchi. My recent research interests have been in studying 2D materials and energy materials using novel techniques in time-resolved multi-dimensional photoemission spectroscopy developed here at OIST.

Yumi Ito

yumi.ito ('at'oist.jp)

[April 2015 - present]

I began my career at Texas State University in September 2004 as a part-time editorial assistant and joined the staff full-time for Dani Unit as an administrative assistant in April 2015. My key element for the unit is caring and warmth in assisting them in achieving their objectives from administrative side, and in helping them have a laugh and fun. Favoring trip and movies, I enjoy spending time with family and friends. An oni-wife and a mother of a King-Kong baby boy.

Michael Man

michael.man (‘at’ oist.jp)

Staff Scientist
[December 2017 - present]

Postdoc
[December 2012 - December 2017]

I received both my master and PhD degrees from the Hong Kong University of Science and Technology (HKUST). My main research interest is in the growth and characterization of nanostructures/ultrafilm films using a powerful and versatile technique called low energy electron microscopy and photoemission electron microscopy (LEEM/PEEM). LEEM/PEEM is capable of performing time and spatially resolved structural, electronic and chemical state measurements at spatial resolution down to the nanometer range. With this instrument, for example, we can study the correlation between morphology and band structure in inhomogeneous nanostructures such as in few layer graphene; we can also examine the surface magnetic state and image the dynamics in magnetic domain structure in variety of magnetic nanomaterials. I joined Prof. Dani’s group in OIST in December 2012. Together, we seek to combine my experience in LEEM/PEEM microscopy with the group’s expertise in ultrafast spectroscopy techniques. One of our goals is in the investigation and visualization of the ultrafast dynamics in nanostructures.

Julien Madéo

julien.madeo ('at' oist.jp)

Staff Scientist
[July 2019 - present]

Postdoc
[July 2014 - June 2019]
[February 2012 - April 2012]

I did my PhD in Laboratoire Pierre Aigrain at Ecole Normale Supérieure in Paris where I studied quantum cascade lasers using THz time-domain spectroscopy and their optical nonlinearities for wavelength conversion. In 2012, I visited OIST for a few months to provide help in building the first lab of the FSU. Then, I came back to Paris for two years in Matériaux et Phénomènes Quantiques, Paris 7 University to study microcavity THz sources and InAs/AlSb based quantum cascade lasers. Since 2014, I am back in the FSU and my current interests cover: THz optoelectronics and devices, ultrafast and nonlinear optics as well as 2D materials and heterostructures.

Filchito Renee Bagsican

filchitorenee.bagsican ('at' oist.jp)

[April 2021 - present]

I received my degree in Doctor of Engineering from Osaka University, Osaka, Japan, where I studied laser terahertz (THz) emission microscopy (LTEM) and its application in probing gas adsorption in atomically-thin two-dimensional materials like graphene and tungsten disulfide. For postdoctoral work, I further demonstrated the applications of LTEM to studying the dynamics of free carriers and excitons in electrically-biased carbon nanotube films. Here in the Dani Unit at OIST, we seek to use my experience in optical systems to extend the limits of high-harmonic generation technology for basic science and industrial applications.

Jacques Hawecker

jacques.hawecker ('at' oist.jp)

[February 2022 - present]

I obtained my physics Ph.D. in 2021 researching within the Nano-THz group in the Laboratoire de l’École Normale Supérieure (LPENS) in Paris. During my Ph.D. I probed two different aspects of modern physics: light-matter interactions and quantum materials. To access this physics, I developed a THz time domain spectroscopy (TDS) system capable of probing THz intersubband polaritonic systems at an ultrafast time scale while resonantly pumping one of the polariton branches with a THz quantum cascade laser. Another aspect of my work was to explore and understand the THz emission from different types of spintronic heterostructures. During my Ph.D. research, I developed a keen interest towards quantum materials and light-matter interactions with a strong emphasis on ultrafast phenomenon. I joined the Femtosecond Spectroscopy Unit at OIST in February 2022, where I will be able to explore in depth this intriguing physics.

Ruotian Chen

ruotian.chen ('at' oist.jp)

[June 2023 - present]

I received my Bachelor’s degree in chemistry from the University of Science and Technology of China in June 2013 and received my PhD in Physical Chemistry from Dalian Institute of Chemical Physics (DICP), Chinese academy of sciences, in January 2020 with Prof. Can Li. Thereafter, I have been an associate professor at the State Key Laboratory of Catalysis and the Dalian National Laboratory for Clean Energy in DICP. My research focuses on understanding microscopic processes and the underlying mechanisms of photocatalytic solar energy conversion and leveraging these understandings for rational photocatalyst design. To understand the complex photocatalytic processes, we have developed and employed functional scanning probe microscopy and spatially resolved surface photovoltage (SPV) techniques in DICP to directly map charge separation and transfer processes at nanoscale, and we have also developed operando potential and SPV measurements in solution to reveal charge transfer mechanism at semiconductor/solution interface. I joined the femtosecond spectroscopy unit at OIST to seek the applications of TR-PEEM and Tr-µ-ARPES in photocatalysis for gaining new insights into photocatalytic charge transfer processes in a spatiotemporally resolved fashion.

Takumi Fukuda

takumi.fukuda ('at' oist.jp)

[April 2024 - present]

I received the Doctor of Philosophy (Engineering) in March 2024 at the University of Tsukuba, Japan, where I studied light-induced electronic and structural dynamics in two-dimensional (2D) layered materials investigated using two kinds of time-resolved pump-probe techniques: coherent phonon spectroscopy based on transient reflectivity changes and ultrafast electron diffraction measurements. Particularly, my research during my Ph.D. journey focused on non-equilibrium transient phenomena arising from electron-phonon interactions, such as photocarrier-driven structural phase transitions and phonon-driven quasiparticle states, mainly in Molybdenum ditelluride polymorphs under various photoexcitation conditions. I joined the Femtosecond Spectroscopy Unit in April 2024 to further explore the intriguing non-equilibrium physics of 2D and other quantum materials by time-resolved ARPES techniques.

Viktoras Lisicovas

viktoras.lisicovas ('at' oist.jp)

Technology Pioneer Fellow
[May 2021 - present]

Junior Research Fellow
[April 2020 - March 2021]

PhD Student
[March 2014 - April 2020]

I graduated from Jacobs University in Bremen, Germany with a degree in Biochemistry and Cell Biology. Later, I have worked in the Laboratory of Biophysics and Applied Pharmacology at ENS Cachan. At OIST my interest lies in studying the basic mechanisms of memory in small networks. I joined Femtosecond Spectroscopy Unit to pursue improvements in optical imaging techniques for basic neuroscience applications.

Sathvik Ajay Iyengar

sathvik.iyengar ('at' oist.jp)

Research Fellow
[April 2024 - present]

I'm a materials engineer and PhD fellow working in Prof. Pulickel Ajayan's lab at Rice University. My research involves synthesizing and fabricating novel 2D material-based structures and understanding their structural, chemical, and electronic properties for emerging device architectures. As a 2024 JSPS Fellow, I plan to hone and apply my skills at the Femtosecond Spectroscopy Unit at OIST, focusing on sample fabrication to study trion imaging in gated Moiré heterostructures. I'm fortunate to have been named a 2023 Inaugural Quad Fellow—one of the 3% selected for a program initiated by the governments and leaders of Japan, the United States, Australia, and India, and announced by the White House. In my spare time, I learn professional-level Japanese, play Carnatic Indian music on the violin, and enjoy gaming on the Nintendo Switch. My goal is to one day lead a research team that thrives on confidence and creativity, bridging diverse disciplines and cultures.

Xing Zhu

xing.zhu1 ('at' oist.jp)

PhD Student
[September 2019 - present]

Rotation Student
[May 2019 - August 2019]

Intern
[October 2017 - June 2018]

I received my bachelor from South University of Science and Technology of China. I join the femtosecond spectroscopy unit as research intern for six months. Previously I worked on the magnetic and optical properties of new-rising 2D materials from first-principles calculation. And now my research interests focus on the terahertz and its applications in imaging and spectroscopy. In FSU, I’ll study strong-field/broadband THz generation and THz spectroscopy of magnetic materials.

Maria-Carla Lupu

mariacarla.lupu ('at' oist.jp)

PhD Student
[September 2021 - present]

Rotation Student
[May 2021 - August 2021]

I received both my bachelor and master degrees at University Politehnica of Bucharest, in Romania. My master program was about engineering and applications of lasers and particle accelerators. For my master thesis I worked on the implementation of an adaptive optics system in a high-power laser facility. I joined FSU as a rotation student, where I will work on high harmonic generation.

Prajakta Kokate

prajakta.kokate ('at' oist.jp)

PhD Student
[January 2022 - present]

Rotation Student
[September 2021 - December 2021]

I graduated from the Indian Institute of Science Education and Research (IISER) Kolkata in June 2020 with physics as my major subject. I started my Ph.D. studies at OIST in January 2021 and joined the Femtosecond Spectroscopy Unit for my third-term lab rotation. I have a background in ultrafast spectroscopy (THz-TDS) as part of my Master's thesis. As a rotation student, my work will focus on understanding and doing measurements using photoemission electron microscopy (PEEM).

Harley Suchiang

harley.suchiang ('at' oist.jp)

PhD Student
[May 2023 - present]

Rotation Student
[May 2022 - August 2022]

I completed my BS-MS dual degree program at the Indian Institute of Science Education and Research (IISER) in Kolkata, India. For my master's project, I studied the spin-orbit interaction of light in plasmonic metasurfaces using Muller polarimetry. As a graduate student at OIST, my first lab rotation will be at the Femtosecond Spectroscopy Unit (FSU) where I will be making an XUV beamline for TR-ARPES experiments.

Nanami Tomoda

nanami.tomoda ('at' oist.jp)

PhD Student
[May 2023 - present]

Rotation Student
[January 2023 - April 2023]

I received my undergraduate degree from Tokyo university of science with a B. Eng. in Chemical Engineering. I was an internship student in Qi unit from 2020 to 2021 and studied interface degradation of each perovskite solar cell layer. My first rotation was Quantum Material Science Unit, and my second was Organic and Carbon Nanomaterials Unit. As shown in my previous research, I am interested in material science. In this unit, I am working partly on TMDC heterostructures project to explore non-equilibrium excitonic insulator physics and valleytronics.

Amrita Mitra

amrita.mitra ('at' oist.jp)

Intern Student
[May 2023 - present]

I am soon to graduate with a BS-MS dual degree majoring in Physics and minoring in Chemistry from the Indian Institute of Science Education and Research (IISER) Bhopal. My Master's Thesis, is on the biexciton and polaron dynamics in metal halide perovskites using pump-probe Femtosecond Transient Absorption Spectroscopy and also studied ab-initio theory for polarons. I joined the FSU to perform TR-PEEM experiments in perovskites.

Poon Yan Thong

yan.poon ('at' oist.jp)

Intern Student
[April 2024 - present]

I hold a bachelor's degree in science with a specialization in Materials Science from the University of Malaya (UM), Malaysia. My interests lie predominantly in the field of Materials Science, with a particular focus on semiconductors. Eager to deepen and expand my knowledge, I embark on a six-month journey with the Femtosecond Spectroscopy Unit, where I will be exploring different topics in two-dimensional materials and ultrafast spectroscopy.

Joan Martin Gascue

joan.gascue ('at' oist.jp)

Intern Student
[March 2024 - present]

After doing a French scientific preparatory class, I joined the engineering school Mines de Paris, where I got my degree in 2023. I am currently doing a master's in quantum engineering at École Normale Supérieure in Paris, where I have been studying light-matter interactions in quantum materials, as well as quantum computing. I also worked with trapped ions systems for quantum simulations during an internship at ETH Zurich. I am joining FSU as an intern to do my master thesis in time-resolved multi-dimensional photoemission spectroscopy.