All Publications

  • Tunable infrared light emission from MoS2/WSe2 heterostructures Karni, O., Barre, E., Lau, S., Gillen, R., Yue, E., Gal, L., Yaffe, T., Kim, B., Watanabe, K., Taniguchi, T., Orenstein, M., Maultzsch, J., Barmak, K., Page, R. H., Heinz, T. F., IEEE IEEE. 2020
  • Infrared Interlayer Exciton Emission in MoS2/WSe2 Heterostructures PHYSICAL REVIEW LETTERS Karni, O., Barre, E., Lau, S., Gillen, R., Ma, E., Kim, B., Watanabe, K., Taniguchi, T., Maultzsch, J., Barmak, K., Page, R. H., Heinz, T. F. 2019; 123 (24)
  • Infrared Interlayer Exciton Emission in MoS_{2}/WSe_{2} Heterostructures. Physical review letters Karni, O., Barré, E., Lau, S. C., Gillen, R., Ma, E. Y., Kim, B., Watanabe, K., Taniguchi, T., Maultzsch, J., Barmak, K., Page, R. H., Heinz, T. F. 2019; 123 (24): 247402


    We report light emission around 1 eV (1240 nm) from heterostructures of MoS_{2} and WSe_{2} transition metal dichalcogenide monolayers. We identify its origin in an interlayer exciton (ILX) by its wide spectral tunability under an out-of-plane electric field. From the static dipole moment of the state, its temperature and twist-angle dependence, and comparison with electronic structure calculations, we assign this ILX to the fundamental interlayer transition between the K valleys in this system. Our findings gain access to the interlayer physics of the intrinsically incommensurate MoS_{2}/WSe_{2} heterostructure, including moiré and valley pseudospin effects, and its integration with silicon photonics and optical fiber communication systems operating at wavelengths longer than 1150 nm.

    View details for DOI 10.1103/PhysRevLett.123.247402

    View details for PubMedID 31922842

  • An integrated single- and two-photon non-diffracting light-sheet microscope REVIEW OF SCIENTIFIC INSTRUMENTS Lau, S., Chiu, H., Zhao, L., Zhao, T., Loy, M. T., Du, S. 2018; 89 (4): 043701


    We describe a fluorescence optical microscope with both single-photon and two-photon non-diffracting light-sheet excitations for large volume imaging. With a special design to accommodate two different wavelength ranges (visible: 400-700 nm and near infrared: 800-1200 nm), we combine the line-Bessel sheet (LBS, for single-photon excitation) and the scanning Bessel beam (SBB, for two-photon excitation) light sheet together in a single microscope setup. For a transparent thin sample where the scattering can be ignored, the LBS single-photon excitation is the optimal imaging solution. When the light scattering becomes significant for a deep-cell or deep-tissue imaging, we use SBB light-sheet two-photon excitation with a longer wavelength. We achieved nearly identical lateral/axial resolution of about 350/270 nm for both imagings. This integrated light-sheet microscope may have a wide application for live-cell and live-tissue three-dimensional high-speed imaging.

    View details for DOI 10.1063/1.5020154

    View details for Web of Science ID 000431139400024

    View details for PubMedID 29716382

  • Multicolor 4D Fluorescence Microscopy using Ultrathin Bessel Light Sheets SCIENTIFIC REPORTS Zhao, T., Lau, S. C., Wang, Y., Su, Y., Wang, H., Cheng, A., Herrup, K., Ip, N. Y., Du, S., Loy, M. M. 2016; 6


    We demonstrate a simple and efficient method for producing ultrathin Bessel ('non-diffracting') light sheets of any color using a line-shaped beam and an annulus filter. With this robust and cost-effective technology, we obtained two-color, 3D images of biological samples with lateral/axial resolution of 250 nm/400 nm, and high-speed, 4D volume imaging of 20 μm sized live sample at 1 Hz temporal resolution.

    View details for DOI 10.1038/srep26159

    View details for Web of Science ID 000375992000001

    View details for PubMedID 27189786

    View details for PubMedCentralID PMC4870613