material compatibility and ease of integration, in addition to the unique and
diverse optoelectronic properties of layered materials (such as graphene,
transition metal dichalcogenides and black phosphorous) have generated
significant interest in their utilization in nanophotonic devices. While
initial nanophotonic experiments primarily focused on light-sources,
modulators, and detectors, recently researchers have also demonstrated
nonlinear optical devices using layered materials. The extreme thinness of the
materials however, limit the effective light-matter interaction. This problem
can be solved by using an optical resonator, where light is confined both
temporally and spatially to enhance the light-matter interaction. I will talk
about some of the recent cavity-2D material devices developed in my lab. These
devices include optically pumped lasers , cavity enhanced LED  and second harmonic generating devices . I will explain how layered
materials present a unique opportunity to engineer the overlap between modes at
different harmonic frequencies for efficient nonlinear optics . I will also talk about some of the
new type of cavities we are exploring in our lab using dielectric freeform
metasurfaces , which can operate on
two-dimensional signal, or an image. Using nonlinear 2D materials inside such
cavity we can potentially perform cavity enhanced nonlinear image processing.
 S. Wu, S. Buckley, J. R.
Schaibley, L. Feng, J. Yan, D. G. Mandrus, F. Hatami, W. Yao, J. Vucˇkovic´, A.
Majumdar, and X. Xu, "Monolayer semiconductor nanocavity lasers with
ultralow thresholds," Nature, vol.
520, pp. 69-72, 2015.
 C.-H. Liu, G. Clark, T. Fryett, S. Wu, J. Zheng, F. Hatami, X.
Xu, and A. Majumdar, "Nanocavity Integrated van der Waals Heterostructure
Light-Emitting Tunneling Diode," Nano
Letters, 2016/12/07 2016.
 K. F. Taylor, L. S. Kyle, Z. Jiajiu, L. Chang-Hua, X.
Xiaodong, and M. Arka, "Silicon photonic crystal cavity enhanced
second-harmonic generation from monolayer WSe 2," 2D Materials, vol. 4, p. 015031, 2017.
 T. Fryett, A. Zhan, and A. Majumdar, "Phase matched
nonlinear optics via patterning layered materials," arXiv:1706.09392, 2017.
 A. Zhan, S. Colburn, C. M. Dodson, and A.
Majumdar, "Metasurface Freeform Nanophotonics," Scientific Reports, vol. 7, p. 1673, 2017/05/10 2017.