Department of Chemistry at Columbia University, New York
WELCOME TO DEL-LABS
Directing Electrons with Light

LATEST NEWS
11/2023
James' paper describing new transport phenomena in superatomic solids, including ballistic excitons through microscopic superradiance, appears in JPCL!
10/2023
Jack's groundbreaking paper on room-temperature ballistic exciton transport in a superatomic semiconductor appears in Science! Featuring awesome materials from the Roy lab and awesome theory from the Berkelbach group. Read Ellen Neff's press release here.
10/2023
Shan-Wen's paper on ultrafast imaging of phonon-polariton propagation appears in Nano Letters! Check out how you can use visible light and a 2D semiconductor sensor layer to probe mid-IR phonon-polaritons with femtosecond resolution and few-nanometer precision.
06/2023
Ding and Arkajit's comprehensive work on imaging polariton transport and polariton-lattice interactions appears in Nature Communications!
06/2023
Congratulations to Yongseok for receiving the prestigious Sejong Science Postdoctoral Fellowship!
06/2023
We're delighted to welcome Emma Lian from Stony Brook University for a summer REU!
05/2023
Congratulations to Ding for being awarded the prestigious Kathy Chen Fellowship for excellence in Chemistry! And congratulations to Paul for being awarded the Miller Teaching Award! Both very well deserved.
04/2023
Arkajit and Ding's paper on the development of a microscopic theory of multimode polariton dispersion appears in Nano Letters, an important paper detailing the correct use of coupled oscillator type models for multi-mode microcavities.
Read all news here.
RESEARCH
The efficient transport and interconversion of energy between photons, electrons, ions and heat underpins life on earth. In modern technologies ranging from solar panels to computers, batteries and health sensors, energy moves slowly, randomly and often inefficiently towards target conversion sites. We aim to direct energy flow in emerging materials in ways that are targeted and efficient, moving beyond random motion to unleash new paradigms for extracting more energy from solar panels, storing more energy in batteries, speeding up information transport and processing, and exploiting correlated electronic systems for new applications.

We use light as a powerful stimulus to initiate, image and control electronic behavior in emerging materials on extreme spatiotemporal scales. Questions we explore include:
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How do we image individual electrons moving and interacting with their surroundings in material lattices?
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How do we control the direction and speed at which energy packets move towards functional targets?
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How do we unlock exotic emergent phenomena and exploit them in modern devices?
The ongoing explosion of discoveries in quantum, meta- and nanomaterials provides the perfect platform for us to answer these questions now.
Super-resolution imaging
of electronic transport and material energy landscapes

Optical control of nuclear-electronic coupling and energy flow on material mesoscales

Optical manipulation of strongly correlated electronic behavior with confined light

In the process of answering these questions, we invent new tools capable of non-invasively imaging events happening over femtoseconds to hours at the single-nanometer scale. These tools are often relevant to a broad range of scientific disciplines: think taking movies of self-assembling biological or material building blocks, of neurons emitting action potentials, and of non-dissipative electronic transport in superconductors.
In addition to gaining a deep fundamental understanding of light-matter interactions, students and postdocs in the group acquire experience in nonlinear optics, super-resolution microscopy, ultrafast visible, IR and terahertz spectroscopy, and materials design and characterization. We collaborate broadly with both theoretical and experimental research groups at Columbia and beyond.
THE TEAM


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Postdoctoral scholar, 2016-2019
Ginsberg group, University of California, Berkeley
Doctoral Prize Fellow, 2015
PhD Physical Chemistry, 2010-2014
Weinstein group, University of Sheffield
BSc Chemistry, 2015-2019
National Taiwan University
BA Chemistry and Global Health, 2015-2019
Washington University in St. Louis



BSc Chemistry, 2014-2019
Wuhan University
Visiting researcher, North Carolina
State University
BS Chemistry & Physics, 2016-2020
University of California, Los Angeles
BS Chemistry, 2016-2020
University of Texas at Austin



PhD Chemistry, 2017-2021
Imperial College London (U.K.)
BS Materials Science, 2017-2021
Northwestern University
BS Chemistry, 2014-2018
MEd Curriculum and Instruction, 2018-2019
University of Maryland, College Park



BS Chemistry, 2018-2022
Bard College
PhD Chemistry, 2015-2021
Yonsei University (South Korea)
BA Chemistry 2022 -
Columbia University

BS Chemistry 2020 -
Stony Brook University
Read more about the team here.
We continue to look for motivated students and postdocs interested in spectroscopy, microscopy and materials science to join the group. Postdoc candidates have a strong background in chemical physics or physical chemistry and experience with one or a combination of the following: ultrafast spectroscopy, super-resolution microscopy, quantum materials, nonlinear optics. Contact Milan for more information.
SELECTED PUBLICATIONS
Baxter J, Koay C, Xu D, Cheng SW, Tulyagankhodjaev J, Shih P, Roy X, Delor M (2023). Coexistence of Incoherent and Ultrafast Coherent Exciton Transport in a Two-Dimensional Superatomic Semiconductor. The Journal of Physical Chemistry Letters, vol. 14, pp. 10249-10256.
Tulyagankhodjaev J, Shih P, Yu J, Russell J, Chica D, Reynoso M, Su Haowen, Stenor A, Roy X, Berkelbach T, Delor M (2023). Room Temperature Wavelike Exciton Transport in a van der Waals Superatomic Semiconductor. Science, vol. 382, pp. 438-442.
Cheng SW, Xu D, Su H, Baxter J, Holtzman L, Watanabe K, Taniguchi T, Hone J, Barmak K, Delor M (2023). Optical Imaging of Ultrafast Phonon-Polariton Propagation through an Excitonic Sensor. Nano Letters, vol. 23, pp. 9936-9942.
Xu D, Mandal A, Baxter J, Cheng SW, Lee I, Su H, Liu S, Reichman D, Delor M (2023). Ultrafast imaging of polariton propagation and interactions. Nature Communications, vol. 14, 3881.
Su H, Xu D, Cheng SW, Li B, Liu S, Watanabe K, Taniguchi T, Hone J, Delor M (2022). Dark-exciton driven energy funneling into dielectric inhomogeneities in two-dimensional semiconductors. Nano Letters, vol. 22, pp. 2843-2850.
Delor M, Weaver H, Yu Q, Ginsberg N (2020).
Imaging material functionality through 3D nanoscale tracking of energy flow
Nature Materials, vol. 19, pp. 56-62.
Delor M, Archer S, Keane T, Meijer A, Sazanovich I, Greetham G, Towrie M, Weinstein J (2017).
Directing the path of light-induced electron transfer at a molecular fork using vibrational excitation
Nature Chemistry, vol. 9, pp. 1099-1104.
Delor M, Scattergood P, Sazanovich I, Parker A, Greetham G, Meijer A, Towrie M, Weinstein J (2014).
Toward control of electron transfer in donor-acceptor molecules by bond-specific infrared excitation
Science, vol. 346, pp. 1492-1495.
CONTACT
Columbia University
Department of Chemistry
3000 Broadway, 117 Havemeyer Hall
New York, NY 10027
Office: 506 Havemeyer
Lab: 117 Havemeyer
