Publications


2021


Artificial Optic-neural Synapse Based on Floating-gate Phototransistor for Machine Vision

Jun Tao, Juan Sanchez Vazquez, Rehan Kapadia
2021 Device Research Conference (DRC), 1-2

 

Increasing the Hot‐Electron Driven Hydrogen Evolution Reaction Rate on a Metal‐Free Graphene Electrode

Hyun Uk Chae, Ragib Ahsan, Jun Tao, Stephen B. Cronin, Rehan Kapadia
Advanced Materials Interfaces 8 (6), 2001706

 

Hot electron emission from waveguide integrated lanthanum hexaboride nanoparticles

Fatemeh Rezaeifar, Hyun Uk Chae, Ragib Ahsan, Rehan Kapadia
Applied Physics Letters 118 (7), 071108

 

Contact photolithography-free integration of patterned and semi-transparent indium tin oxide stimulation electrodes into polydimethylsiloxane-based heart-on-a-chip devices for streamlining physiological recordings

Joycelyn K Yip, Debarghya Sarkar, Andrew P Petersen, Jennifer N Gipson, Jun Tao, Salil Kale, Megan L Rexius-Hall, Nathan Cho, Natalie N Khalil, Rehan Kapadia, Megan L McCain
Lab on a Chip 21 (4), 674-687

 
 

2020


Low Temperature Growth of Crystalline Semiconductors on Nonepitaxial Substrates

Debarghya Sarkar, Sizhe Weng, Dingzhu Yang, Jun Tao, Shreyas Naik, Salil Kale, Hyun Uk Chae, Yunpeng Xu, Bamdad Mesri, Stephen B. Cronin, Frank Greer, Rehan Kapadia
Advanced Materials Interfaces
 

Monolithic High-Mobility InAs on Oxide Grown at Low Temperature

Debarghya SarkarJun TaoRagib AhsanDingzhu YangThomas OrvisSizhe WengFrank GreerJayakanth RavichandranConstantine Sideris, Rehan Kapadia
ACS Applied Electronic Materials

 

Tunable Onset of Hydrogen Evolution in Graphene with Hot Electrons

Hyun Uk Chae, Ragib Ahsan, Jun Tao, Stephen B Cronin, Rehan Kapadia
Nano Letters 

 

Performance Limits of Graphene Hot Electron Emission Photoemitters

Ragib Ahsan, Mashnoon Alam Sakib, Hyun Uk Chae, Rehan Kapadia
Phys. Rev. Applied 

 

Auger Suppression of Nanotube Incandescence in Individual Suspended CNT pn-junctions

Bo Wang, Sisi Yang, Yu Wang, Ragib Ahsan, Xiaowei He, Younghee Kim, Han Htoon, Rehan Kapadia, Demis D John, Brian Thibeault, Stephen K Doorn, Stephen B Cronin
ACS Applied Materials & Interfaces 


2019


Tunable Onset of Hydrogen Evolution in Graphene with Hot Electrons

Hyun Uk Chae, Ragib Ahsan, Jun Tao, Stephen B Cronin, Rehan Kapadia
Nano Letters 

 

Performance Limits of Graphene Hot Electron Emission Photoemitters

Ragib Ahsan, Mashnoon Alam Sakib, Hyun Uk Chae, Rehan Kapadia
ACS applied materials & interfaces 

 

Auger Suppression of Nanotube Incandescence in Individual Suspended CNT pn-junctions

Bo Wang, Sisi Yang, Yu Wang, Ragib Ahsan, Xiaowei He, Younghee Kim, Han Htoon, Rehan Kapadia, Demis D John, Brian Thibeault, Stephen K Doorn, Stephen B Cronin
ACS Applied Materials & Interfaces 

 

Hot-electron emission processes in waveguide-integrated graphene

Fatemeh Rezaeifar, Ragib Ahsan, Qingfeng Lin, Hyun Uk Chae, Rehan Kapadia
Nature Photonics

 

Optical modulation of on-chip thermionic emission using resonant cavity coupled electron emitters

Fatemeh Rezaeifar Bayat, Rehan Rashid Kapadia
US Patent 10,403,484

 

High Quantum Efficiency Hot Electron Electrochemistry

Hyun Uk Chae, Ragib Ahsan, Qingfeng Lin, Debarghya Sarkar, Fatemeh Rezaeifar, Stephen B Cronin, Rehan Kapadia
Nano letters

 

Integrated photonics for low transverse emittance, ultrafast negative electron affinity GaAs photoemitters

L Blankemeier, F Rezaeifar, A Garg, R Kapadia
Journal of Applied Physics

 

Epitaxial growth and dielectric characterization of atomically smooth 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 thin films

Yang Liu, Zheng Wang, Arashdeep Singh Thind, Thomas Orvis, Debarghya Sarkar, Rehan Kapadia, Albina Y Borisevich, Rohan Mishra, Asif Islam Khan, Jayakanth Ravichandran
Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films

 


2018


 

Nanowire Field-Effect Transistors

Debarghya Sarkar, Ivan S Esqueda, Rehan Kapadia
Advanced Nanoelectronics: Post‐Silicon Materials and Devices

 

Growth of single crystal III-V semiconductors on amorphous substrates

Kevin Chen, Rehan Kapadia, Ali Javey
US Patent 10,087,547

 

Optimal bandgap in a 2D Ruddlesden–Popper perovskite chalcogenide for single-junction solar cells

Shanyuan Niu, Debarghya Sarkar, Kristopher Williams, Yucheng Zhou, Yuwei Li, Elisabeth Bianco, Huaixun Huyan, Stephen B Cronin, Michael E McConney, Ralf Haiges, R Jaramillo, David J Singh, William A Tisdale, Rehan Kapadia, Jayakanth Ravichandran
Chemistry of Materials

 

Buffer insensitive optoelectronic quality of InP-on-Si with templated liquid phase growth

Debarghya Sarkar, Wei Wang, Qingfeng Lin, Jun Tao, Matthew Mecklenburg, Jayakanth Ravichandran, Rehan Kapadia
Journal of Vacuum Science & Technology B, Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena

 

Confined Liquid Phase Growth of Crystalline Compound Semiconductors on Any Substrate

D. Sarkar, W. Wang, M. Mecklenburg, A. Clough, M. Yeung, C. Ren, Q. Lin, L. Blankemeier, S. Niu, H. Zhao, H. Shi, H. Wang, S. Cronin, J. Ravichandran, M. Luhar, R. Kapadia. 
ACS Nano

 

Mimicking Biological Synaptic Functionality with an Indium Phosphide Synaptic Device on Silicon for Scalable Neuromorphic Computing

D. Sarkar, J. Tao, W. Wang, Q. Lin, M. Yeung, C. Ren, R. Kapadia.
ACS Nano

 


2017


 

Independent tuning of work function and field enhancement factor in hybrid lanthanum hexaboride-graphene-silicon field emitters

F. Rezaeifar, Q. Lin, X. Chen, T. M. Mattox, A. Garg, A. Clough, N. Poudel, L. Blankemeier, D. Sarkar, S. B. Cronin, R. Kapadia. 
Journal of Vacuum Science & Technology B, Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena

 

Prevention of surface recombination by electrochemical tuning of TiO2-passivated photocatalysts

B. Hou, F. Rezaeifar, J. Qiu, G. Zeng, R. Kapadia, S.B. Cronin.
Applied Physics Letters

 

Avalanche Photoemission in Suspended Carbon Nanotubes: Light Without Heat

B. Wang, F. Rezaeifar, J.I. Chen, S. Yang, R. Kapadia, S.B. Cronin
ACS Photonics

 

A Scalable Indium Phosphide Thin-Film Nanophotonics Platform for Photovoltaic and Photoelectrochemical Devices

Q. Lin, D. Sarkar, Y. Lin, M. Yeung, L. Blankemeier, J. Hazra, W. Wang, S. Niu, J. Ravichandran, Z. Fan, R. Kapadia.
ACS Nano

 

Hot Electron-Driven Photocatalytic Water Splitting

B. Hou, L. Shen, H. Shi, R. Kapadia, S. B. Cronin. 
Physical Chemistry Chemical Physics

 

Band-Gap Control via Structural and Chemical Tuning of Transition Metal Perovskite Chalcogenides

S. Niu, H. Hyuyan, Y. Liu, M. Yeung, K. Ye, L. Blankemeier, T. Orvis, D. Sarkar, D. J. Singh, R. Kapadia, J. Ravichandran.
Advanced Materials

 


2016


Efficient and ultrafast optical modulation of on-chip thermionic emission using resonant cavity coupled electron emitters

F. Rezaeifar, R. Kapadia.
Journal of Vacuum Science & Technology B

 

Direct growth of single-crystalline III–V semiconductors on amorphous substrates

K. Chen, R. Kapadia, A. Harker, S.B. Desai, J.S. Kang, S. Chuang, M. Tosun, C.-S. Fella, M. Tsang, Y. Zeng, D. Kiriya, S. Madhvapathy, M. Hettick, J. Mastandrea, M. Amani, S. Cabrini, J.W. Ager, D.C. Chrzan, Y.-L. Chueh, A. Javey.
Nature Communications

 

III‐Vs at scale: a PV manufacturing cost analysis of the thin film vapor–liquid–solid growth mode

M. Zheng, K. Horowitz, M. Woodhouse, C. Battaglia, R. Kapadia, A. Javey.
Progress in Photovoltaics: Research and Applications

 


2015


A Comparison of Photocurrent Mechanisms in Quasi-Metallic and Semiconducting Carbon Nanotube pn-Junctions

S. W. Chang, J. Hazra, M. Amer, R. Kapadia, S. B. Cronin.
ACS Nano

 

Photocurrent spectroscopy of exciton and free particle optical transitions in suspended carbon nanotube pn-junctions

S. W. Chang, J. Theiss, J. Hazra, M. Aykol, R. Kapadia, S. B. Cronin.
Applied Physics Letters

 

Quantum Well InAs/AlSb/GaSb Vertical Tunnel FET With HSQ Mechanical Support

Y. Zeng, C.I. Kuo, C. Hsu, M. Nejmzadeh, A. Sachid, R. Kapadia, C. Yeung, E. Y. Chang, C. Hu, A. Javey.
IEEE Trans. Nanotechnol.

 

Role of TiO2 Surface Passivation on Improving the Performance of p-InP Photocathodes

Y. Lin, R. Kapadia, J. Yang, M. Zheng, K. Chen, M. Hettick, X. Yin, C. Battaglia, I. D. Sharp, J. W. Ager, A. Javey.  
Journal of Physical Chemistry C

 

Photovoltaic Material Characterization With Steady State and Transient Photoluminescence

X. Wang, J. Bhosale, J. Moore, R. Kapadia, P. Bermel, A. Javey, M. Lundstrom.
IEEE J. Photovolt.

2014 and Prior

S. B. Desai, G. Seol, J. S. Kang, H. Fang, C. Battaglia, R. Kapadia, J. W. Ager, J. Guo, and A. Javey. “Strain-Induced Indirect to Direct Bandgap Transition in Multilayer WSe2”, Nano Letters, ASAP, 2014.

S. Chuang, C. Battaglia, A. Azcatl, S. McDonnell, J. S. Kang, X. Yin, M. Tosun, R. Kapadia, H. Fang, R. M. Wallace, A. Javey, “MoS2 P-type Transistors and Diodes Enabled by High Workfunction MoOx Contacts”, Nano Letters, 14 (3), 1337–1342, 2014.

R. Kapadia, Z. Yu, M. Hettick, J. Xu, M. S. Zheng, C.-Y. Chen, A. D. Balan, D. C. Chrzan, A. Javey, “Deterministic nucleation of InP on metal foils with the thin-film vapor-liquid-solid growth mode”, Chemistry of Materials, 26 (3), 1340–1344, 2014.

K. Takei, R. Kapadia, Y. Li, E. Plis, S. Krishna, A. Javey. “Surface Charge Transfer Doping of III-V Nanostructures”, Journal of Physical Chemistry C, 117(34), 17845-17849, 2013.

R. Kapadia*, Z. Yu*, H.-H. H. Wang, M. Zheng, C. Battaglia, M. Hettick, D. Kiriya, K. Takei, P. Lobaccaro, J. W. Beeman, J. W. Ager, R. Maboudian, D. C. Chrzan, A. Javey, “A direct thin-film path towards low-cost large-area III-V photovoltaics”, Scientific Reports, 3, 2275; DOI:10.1038/srep02275, 2013.
*Equal contribution from authors

Y. Zeng, C.-I Kuo, R. Kapadia, C.-Y. Hsu, A. Javey, C. Hu, “2-D to 3-D tunneling in InAs/AlSb/GaSb quantum well heterojunctions”, Journal of Applied Physics, 114, 024502, 2013. 

S. Chuang, R. Kapadia, H. Fang, T. C. Chang, W.-C. Yen, Y.-L. Chueh, A. Javey, “Near-ideal electrical properties of InAs/WSe2 van der Waals heterojunction diodes”, Applied Physics Letters,102, 242101, 2013. (cover article)

K. Takei, R. Kapadia, H. Fang, E. Plis, S. Krishna, A. Javey, “High quality interfaces of InAs-on-insulator field-effect transistors with ZrO2 gate dielectrics”, Applied Physics Letters, 102, 153513, 2013.

O. Waldmann and A. Persaud and R. Kapadia and K. Takei and A. Javey and T. Schenkel, “Effects on field emission properties of palladium coated carbon nanofibers in a hydrogen plasma”, Thin Solid Films, 534, 488-491, 2013.

S. Chuang, Q. Gao, R. Kapadia, A. C. Ford, J. Guo, A. Javey, “Ballistic InAs Nanowire Transistors”, Nano Letters, 13, 555−558, 2013.

D. Kiriya, M. Zheng, R. Kapadia, J. Zhang, M. Hettick Z. Yu, K. Takei, H.-H. Wang, P. Lobaccaro, A. Javey. “Morphological and spatial control of InP crystal growth using closed-spaced sublimation”, J. Appl. Phys., in press, 2012.

M. H. Lee, K. Takei, J. Zhang, R. Kapadia, M. Zheng, Y.-Z. Chen, J. Nah, T. S. Matthews, Y.-L. Chueh, J. W. Ager, A. Javey. “p-InP nanopillar photocathodes for highly efficient, solar-driven hydrogen production”, Angew. Chem. Int. Ed., 51, 10760–10764, 2012.

H. Ko, R. Kapadia, K. Takei, T. Takahashi, X. Zhang, A. Javey. “Multifunctional, flexible electronic systems based on engineered nanostructured materials”, Nanotechnology, 23, 344001, 2012.

M. Zheng, Z. Yu, T. J. Seok, Y.-Z. Chen, R. Kapadia, K. Takei, S. Aloni, J. W. Ager, M. Wu, Y.-L Chueh, A. Javey, “High Optical Quality Polycrystalline Indium Phosphide Grown on Metal Substrates by MOCVD”, J. Appl. Phys., 111, 123112, 2012.

A. Ford, S. B. Kumar, R. Kapadia, J. Guo, A. Javey, “Observation of degenerate one-dimensional sub-bands in cylindrical InAs nanowires”, Nano Lett., 12 (3), 1340-1343, 2012.

K. Takei, M. Madsen, H. Fang, R. Kapadia, S. Chuang, H.S. Kim, C.-H. Liu, E. Plis, J. Nah, S. Krishna, Y.-L. Chueh, J. Guo, A. Javey, “Nanoscale InGaSb Heterostructure Membranes on Si Substrates for High Hole Mobility Transistors”, Nano Lett., 12, 2060-2066, 2012.

R. Kapadia, Z. Fan, K. Takei, A. Javey. “Nanopillar Photovoltaics: Materials, Processes, and Devices”, Nano Energy, 1, 132-144, 2012.

K. Takei, H. Fang, S. B. Kumar, R. Kapadia, Q. Gao, M. Madsen, H. S. Kim, C.-H. Liu, Y.-L. Chueh, E. Plis, S. Krishna, H. A. Bechtel, J. Guo, A. Javey. “Quantum Confinement Effects in Nanoscale-Thickness InAs Membranes”, Nano Letters, 11, 5008–5012, 2011.

C. L. Pint, K. Takei, R. Kapadia, M. Zheng, A. C. Ford, J. Zhang, A. Jamshidi, R. Bardhan, J. J. Urban, M. Wu, J. W. Ager, M. M. Oye, A. Javey. “Rationally designed, three-dimensional carbon nanotube back-contacts for efficient solar devices”, Advanced Energy Materials, 1, 1040-1045, 2011. 

K. Takei, S. Chuang, H. Fang, R. Kapadia, C.-H. Liu, J. Nah, H. S. Kim, E. Plis, S. Krishna, Y.-L. Chueh, A. Javey. “Benchmarking the performance of ultrathin body InAs-on-insulator transistors as a function of body thickness”, Applied Physics Letters, 99, 103507, 2011.

M. H. Lee, N. Lim, D. J. Ruebusch, A. Jamshidi, R. Kapadia, R. Lee, T. J. Seok, K. Takei, K. Y. Cho, Z. Fan, H. Jang, M. Wu, G. Cho, A. Javey. “Roll-to-Roll Anodization and Etching of Aluminum Foils for High-Throughput Surface Nano-Texturing”, Nano Letters, 11, 3425-3430, 2011.

M. Madsen, K. Takei, R. Kapadia, H. Fang, H. Ko, T. Takahashi, A. C. Ford, M. H. Lee, A. Javey. “Nanoscale Semiconductor “X” on Substrate “Y” – Processes, Devices and Applications”, Advanced Materials, 23, 3115–3127, 2011.

K. Cho, D. J. Ruebusch, M. H. Lee, J. H. Moon, A. C. Ford, R. Kapadia, K. Takei, A. Javey. “Molecular monolayers for conformal, nanoscale doping of InP nanopillar photovoltaics”, Applied Physics Letters, 98, 203101, 2011.

A. Persaud, R. Kapadia, I. Allen, M. Dickinson, K. Takei, A. Javey, T. Schenkel. “Development of a compact neutron source based on field ionization processes”, Journal of Vacuum Science and Technology B, 29(2), 2011.

H. Ko*, K. Takei*, R. Kapadia*, S. Chuang, H. Fang, P. W. Leu, K. Ganapathi, E. Plis, H. S. Kim, S.-Y. Chen, M. Madsen, A. C. Ford, Y.-L. Chueh, S. Krishna, S. Salahuddin, A. Javey. “Ultrathin compound semiconductor on insulator layers for high performance nanoscale transistors”, Nature, 468, 286–289, 2010.
*Equal contribution from authors

O. Ergen, D. Ruebusch, H. Fang, A. Rathore, R. Kapadia, Z. Fan, K. Takei, A. Jamshidi, M. Wu, A. Javey. “Shape-Controlled Synthesis of Single-Crystalline Nanopillar Arrays by Template-Assisted Vapor-Liquid-Solid Process”, Journal of the American Chemical Society, 132 (40), 13972–13974, 2010.

Z. Fan, R. Kapadia, P. Leu, X. Zhang, Y.-L. Chueh, K. Takei, K. Yu, A. Jamshidi, A. Rathore, D. Ruebusch, M. Wu, A. Javey. “Ordered arrays of dual-diameter nanopillars for maximized optical absorption”, Nano Letters, 10, 3823–3827, 2010.

R. Kapadia, Z. Fan, A. Javey. “Design constraints and guidelines for CdS/CdTe nanopillar based photovoltaics”, Applied Physics Letters, 96, 103116, 2010.

Y.-L. Chueh, Z. Fan, K. Takei, H. Ko, R. Kapadia, A. A. Rathore, N. Miller, K. Yu, M. Wu, E. E. Haller, A. Javey. “Black Ge based on crystalline/amorphous core/shell nanoneedle arrays”, Nano Letters, 10, 520-523, 2010.

H. Ko, Z. Zhang, J. C. Ho, K. Takei, R. Kapadia, Y.-L. Chueh, W. Cao, B. A. Cruden, A. Javey. “Flexible Carbon Nanofiber Connectors with Anisotropic Adhesion Properties”, Small, 6, 22-26, 2010.

Z. Fan, D. J. Ruebusch, A. A. Rathore, R. Kapadia, O. Ergen, P. W. Leu, A. Javey. “Challenges and Prospects of Nanopillar Based Solar Cells”, Nano Research, 2, 829-843 2009.

R. Kapadia, H. Ko, Y.-L. Chueh, J. C. Ho, T. Takahashi, Z. Zhang, A. Javey. “Hybrid core-multi-shell nanowire forests for electrical connector applications”, Applied Physics Letters, 94, 263110, 2009.
a. “Nano connections”, Nature Materials, Research Highlights, August 2009.
b. “Nanowires: Plug and play”, Nature Nanotechnology, Research Highlights, July 2009.