PUBLICATIONS

Under Review

*contact PI for manuscripts and pre-prints

ON ULTRAFAST SPECTROSCOPY OF METAMATERIALS

Energy-momentum resolved excitonic lasing in nanoscale random media,
by RPN. Tripathi*, BS. Dhami* and K. Appavoo

An ultrafast perspective on the effect of fabrication processes all-dielectric metasurfaces,
by U. Tiwari and K. Appavoo

Time-varying magnetic and electric resonances in dielectric metasurfaces probed by femtosecond broadband spectroscopy,
by U. Tiwari and K. Appavoo

ON ULTRAFAST SPECTROSCOPY OF ENERGY NANOMATERIALS

Detection of stimulated emission in microstructures of hybrid perovskites probed by energy-momentum spectroscopy,
by RPN. Tripathi*, BS. Dhami*, U. Tiwari and K. Appavoo

ON MACHINE LEARNING OF NANOPHOTONIC ELEMENTS

Machine learning of photonic nanostructures in their environment,
by A. Pant and K. Appavoo

Inverse Design for Dielectric Nanosphere using Machine Learning,
by D. Hoxie, P. Bangalore and K. Appavoo

2016-2022

[41] Revealing ultrafast carrier dynamics of hybrid perovskites at various stages of nucleation and growth kinetics in Advanced Optical Materials (accepted).
B.S. Dhami ‡, R.P. N. Tripathi ‡, D.J. Hoxie and  K. Appavoo 

[40] Angle-resolved polarimetry of hybrid perovskite emission for photonic technologies in Nanoscale (2022).
B.S. Dhami, V. Iyer, A. Pant, R.P. N. Tripathi, E.J. Taylor, B.J. Lawrie, and  K. Appavoo 

[39] Large-Area Lasing in Nanoscale Complex Media: The Critical Role of Local Dielectric Environment in Advanced Optical Materials (2022).
K. Casey, B. S. Dhami, M. A. Paige, M. Y. Sfeir, and K. Appavoo 

[38] Probing Ultrafast Transient Electric and Magnetic Fields in Silicon Metasurfaces in Nonlinear Optics (2021).
U. Tiwari and K. Appavoo 

[37] Plasmonic and Dielectric Nanostructures: Distinguishing Size, Material, and Dielectric Environment via Machine Learning in CLEO (2021) - Science and Innovations: Quantum Photonics and Machine Learning
A. Pant and K. Appavoo 

[36] Doping-driven electronic and lattice dynamics in the phase-change material vanadium dioxide in Physical Review B (2020).
K. Appavoo, J. Nag, B. Wang, W. Luo, G. Duscher, EA. Payzant, MY. Sfeir, ST. Pantelides, RF. Haglund Jr. 

[35] Edge States Drive Exciton Dissociation in Ruddlesden–Popper Lead Halide Perovskite Thin Films in ACS Materials Letters (2020).
ED. Kinigstein, H. Tsai, W. Nie, JC. Blancon, KG. Yager, K. Appavoo, J. Even, MG. Kanatzidis, AD. Mohite, MY. Sfeir. 

[34] Charge transfer states impact the triplet pair dynamics of singlet fission polymers in Journal of Chemical Physics (2020).
G. He, E. Busby, K. Appavoo, Q. Wu, J. Xia, LM. Campos, MY. Sfeir. 

[33] Fourier imaging microscopy of light-emitting hybrid perovskite nanostructures in SPIE: Energy Harvesting and Storage (2020).
RPN Tripathi, BS. Dhami and K. Appavoo. 

[32] Epitaxial VO2 Nanostructures: A Route to Large-Scale, Switchable Dielectric Metasurfaces in ACS Photonics (2018).
F. Ligmajer, L. Kejik, U. Tiwari, M. Qiu, J. Nag, M. Konecny, T. Sikola, W. Jin, RF. Haglund Jr, K. Appavoo, DY. Lei. 

[31] Extremely efficient internal exciton dissociation through edge states in layered 2D perovskites in Science (2017).
W. Nie, JC. Blancon, AJ Neukirch, K. Appavoo, H Tsai, M Chhowalla, MA Alam, MY Sfeir, J. Even J, S. Tretiak, JJ Crochet, G. Gupta and AD. Mohite. 

[30] Ultrafast optical snapshots of hybrid perovskites reveal the origin of multiband electronic transitions in Physical Review B (2017).
Appavoo K, Nie W, Blancon JC, Even J, Mohite AD and MY Sfeir.  

[29] Unravelling photocarrier dynamics beyond the space charge region for PEC water splitting in Chemistry of Materials (2017).
Zhang W,  Yan D, Appavoo K, Cen J, Wu Q, Sfeir MY, and Liu M. 

[28] Light-activated photocurrent degradation and self-healing in perovskite solar cells in Nature Communications (2016).
Nie W, Blancon JC,  Neukirch AJ, Appavoo K, Tsai H, Chhowalla M, Alam MA, Sfeir MY, Katan C, Even J, Tretiak S, Crochet JJ, Gupta G and Mohite AD. 

[27] Polaron Stabilization by Cooperative Lattice Distortion and Cation Rotations in Hybrid Perovskite Materials in Nano Letters (2016).
Neukirch AJ, Nie W, Blancon JC, Appavoo K, Sfeir MY, Katan C, Pedesseau L, Even J, Crochet JJ, Gupta G, Mohite AD and Tretiak S. 

[26] Excitonic Lasing in Solution-Processed Subwavelength Nanosphere Assemblies in Nano Letters (2016).
Appavoo K, Liu X, Menon V and Sfeir MY. 

[25] Exciton Correlations in Intramolecular Singlet Fission in Journal of the American Chemical Society, JACS (2016).
Sanders SN, Kumarasamy E, Pun AB, Appavoo K, Steigerwald ML, Campos LM and Sfeir MY. 

[24] Heterogeneous nucleation in the light-induced phase transition in vanadium dioxide in Journal of Condensed Matter (2016).
Brady NF, Appavoo K, Nag J, Seo, MN, Prasankumar RP, Haglund RF and Hilton DJ. 

2010 - 2015

[23] Ordering at all scales in the non-metallic 133-gold-atom nanoparticle in Science Advances 2015 
Zeng C, Chen Y, Kirschbaum K, Appavoo K, Sfeir MY, Li T, Rosi N and Jin R. 

[22] Quantifying bulk and surface recombination processes in nanostructured water splitting photocatalysts via in situ ultrafast spectroscopy in Nano Letters 2015 
Appavoo K, Liu M, Black CT, Sfeir MY. 

[21] Optically-Triggered Nanoscale Memory Effect in a Hybrid Plasmonic-Phase Changing Nanostructure in ACS Photonics 2015
Lei DY, Appavoo K, Ligmajer F, Sonnefraud Y, Haglund RF and S.A. Maier. 

[20] Hybrid Si-VO2-Au Modulator based on near-field plasmonic coupling in Optics Express 2015 
Markov P, Appavoo K, Haglund RF and Weiss SM. 

[19] Room-Temperature Exciton Lasing in Ultrathin Film of Coupled Nanocrystals in Postdeadline CLEO Science and Innovations 2015 
Appavoo K, Liu X, Menon VM, Sfeir MY.

[18] Doping-controlled coherent electron-phonon coupling in vanadium dioxide in CLEO Science and Innovations 2015 
Appavoo K, Wang B, Nag J, Sfeir MY, Pantelides ST, Haglund RF, 

[17]  Decoupling bulk and surface contributions in water splitting Photocatalysts by in situ ultrafast spectroscopy in CLEO:QELS Fundamental Science OSA Digest 2015
Appavoo K, Liu M, Black CT, Sfeir MY.

[16] Polarization selective phase-change nanomodulator in Nature Scientific Reports 2014
Appavoo K & Haglund RF. 

[15] Enhanced broadband ultrafast detection of ultraviolet emission using optical Kerr gating. Review of Scientific Instruments 2014
Appavoo K & Sfeir MY.

[14] Role of size and defects in ultrafast broadband emission dynamics of ZnO nanostructures. Applied Physics Letters 2014 
Appavoo K, Liu M, Sfeir MY.

[13] Ultrafast phase transition via catastrophic phonon collapse driven by plasmonic hot-electron injection. Nano Letters 2014
Appavoo K, Wang B, Brady N, Seo M, Nag J, Pantelides ST, Prasankumar RP, Hilton DJ, Haglund RF.  (Featured in IEEE spectrum, Science daily, VU, UAB, Nanowerk and Kurzweil)

[12] Switchable plasmon-induced transparency in gold nanoarrays on vanadium dioxide film. J. Vac. Sci. Technol. 2013
McGahan C, Appavoo K, Shapera EP and Haglund RF.

[11] Polarization-Dependent Phase-Changing Nanoswitch.  CLEO:QELS Fundamental Science 2013
Appavoo K and Haglund RF.

[10] Tracking the evolution of electronic and structural properties of VO2 during the ultrafast photoinduced insulator-metal transition. Phys. Rev. B 2013
S. Wall, L. Foglia, D. Wegkamp, K. Appavoo, J. Nag, R. F. Haglund Jr, J. Stähler, M. Wolf.

[9] Electron-beam deposition of vanadium dioxide thin films. Applied Physics A: Materials Science & Processing 2013
Marvel RE*, Appavoo K*, Choi BK, Nag J and Haglund RF.

[8] Ultrafast Metal-Insulator Transition in VO2 Driven by Electron Injection. Postdeadline CLEO:QELS Fundamental Science 2012
Appavoo K, Brady NF, Seo M, Nag J, Prasankumar RP, Hilton DH and Haglund RF.  

[7] Ultrafast Changes in Lattice Symmetry Probed by Coherent Phonons. Nature Commununications 2012
Wall S, Wegkamp D, Foglia F, Appavoo K, Nag J, Haglund RF, Stahler J and Wolf M. 

[6] Role of Defects in Phase Transition of VO2 Nanoparticles Probed by Plasmon Resonance Spectroscopy. Nano Lett. 2012
Appavoo K*, Lei DY*, Sonnefraud Y, Wang B, Pantelides ST, Maier SA and Haglund RF.

[5] Revealing Plasmonic Gap Modes in Particle-on-Film Systems Using Dark-Field Spectroscopy. ACS Nano 2012
Lei DY*, Fernandez-Dominguez AI*, Sonnefraud Y, Appavoo K, Haglund RF, Pendry JB and Maier S. 

[4] Effect of Phase-Transforming Medium on Coherent Electron Dynamics in Gold Nanoantennas. CLEO:QELS Fundamental Science 2011
Appavoo K and Haglund RF.

[3] Detecting Nanoscale Size Dependence in VO2 Phase Transition Using a Split-Ring Resonator Metamaterial. Nano Letters 2011
Appavoo K and Haglund RF. 

[2] Single-Particle Plasmon Resonance Spectroscopy of Phase Transition in Vanadium Dioxide. Optics Letters 2010
Lei DY, Appavoo K, Sonnefraud Y, Haglund RF and Maier SA. 

[1] Spectral Modulation of Single Plasmonic Nanostructures. Synthesis and Photonics of Nanoscale Materials VII, SPIE 2010
Appavoo K, Lei DY, Sonnefraud Y, Ferrara DW, Nag J, Maier SA and Haglund RF.