Cherie R Kagan Research Group

@article{Keller2022,

title = {Sub-5 nm Anisotropic Pattern Transfer via Colloidal Lithography of a Self-Assembled GdF3 Nanocrystal Monolayer},

author = {Austin W. Keller and Emanuele Marino and Di An and Steven J. Neuhaus and Katherine C. Elbert and Christopher B. Murray* and Cherie R. Kagan*},

url = {https://pubs.acs.org/doi/abs/10.1021/acs.nanolett.1c04761},

doi = {10.1021/acs.nanolett.1c04761},

year  = {2022},

date = {2022-02-28},

urldate = {2022-02-28},

journal = {Nano Letters},

volume = {22},

issue = {5},

pages = {1992–2000},

abstract = {Patterning materials with nanoscale features opens many research opportunities ranging from fundamental science to technological applications. However, current nanofabrication methods are ill-suited for sub-5 nm patterning and pattern transfer. We demonstrate the use of colloidal lithography to transfer an anisotropic pattern of discrete features into substrates with a critical dimension below 5 nm. The assembly of monodisperse, anisotropic nanocrystals (NCs) with a rhombic-plate morphology spaced by dendrimer ligands results in a well-ordered monolayer that serves as a 2D anisotropic hard mask pattern. This pattern is transferred into the underlying substrate using dry etching followed by removal of the NC mask. We exemplify this approach by fabricating an array of pillars with a rhombic cross-section and edge-to-edge spacing of 4.4 ± 1.1 nm. The fabrication approach enables broader access to patterning materials at the deep nanoscale by implementing innovative processes into well-established fabrication methods while minimizing process complexity.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Shulevitz2021,

title = {Template-Assisted Self Assembly of Fluorescent Nanodiamonds for Scalable Quantum Technologies},

author = {Henry J. Shulevitz and Tzu-Yung Huang and Jun Xu and Steven Neuhaus and Raj N. Patel and Lee C. Bassett, Cherie R. Kagan},

url = {https://pubs.acs.org/doi/10.1021/acsnano.1c09839

https://arxiv.org/abs/2111.14921},

year  = {2022},

date = {2022-01-13},

urldate = {2021-12-01},

journal = {ACS Nano},

abstract = {Milled nanodiamonds containing nitrogen-vacancy (NV) centers provide an excellent platform for sensing applications as they are optically robust, have nanoscale quantum sensitivity, and form colloidal dispersions which enable bottom-up assembly techniques for device integration. However, variations in their size, shape, and surface chemistry limit the ability to position individual nanodiamonds and statistically study properties that affect their optical and quantum characteristics. Here, we present a scalable strategy to form ordered arrays of nanodiamonds using capillary-driven, template-assisted self assembly. This method enables the precise spatial arrangement of isolated nanodiamonds with diameters below 50 nm across millimeter-scale areas. Measurements of over 200 assembled nanodiamonds yield a statistical understanding of their structural, optical, and quantum properties. The NV centers' spin and charge properties are uncorrelated with nanodiamond size, but rather are consistent with heterogeneity in their nanoscale environment. This flexible assembly method, together with improved understanding of the material, will enable the integration of nanodiamonds into future quantum photonic and electronic devices.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Cai2021,

title = {Chemical and Physical Properties of Photonic Noble-metal Nanomaterials},

author = {Yi-Yu Cai and Yun Chang Choi and Cherie R. Kagan},

url = {https://onlinelibrary.wiley.com/doi/10.1002/adma.202108104},

doi = {10.1002/adma.202108104},

year  = {2021},

date = {2021-12-12},

urldate = {2021-12-12},

journal = {Advanced Materials},

abstract = {Colloidal noble metal nanoparticles are composed of metal cores and organic or inorganic ligand shells. These nanoparticles support size- and shape-dependent plasmonic resonances. They can be assembled from dispersions into artificial metamolecules which have collective plasmonic resonances originating from coupled bright and dark optical electric and magnetic modes that form depending on the size and shape of the constituent nanoparticles and their number, arrangement, and interparticle distance. Nanoparticles can also be assembled into extended two- and three-dimensional metamaterials that are glassy thin films or ordered thin films or crystals, also known as superlattices and supercrystals. The metamaterials have tunable optical properties that depend on the size, shape, and composition of the nanoparticles, and on the number of nanoparticle layers and their interparticle distance. Interestingly, strong light-matter interactions in superlattices form plasmon polaritons. Tunable interparticle distances allow designer materials with dielectric functions tailorable from that characteristic of an insulator to that of a metal, and serve as strong optical absorbers or scatterers, respectively. In combination with lithography techniques, these extended assemblies can be patterned to create subwavelength nanoparticle superstructures and form large-area 2D and 3D metamaterials that manipulate the amplitude, phase, and polarization of transmitted or reflected light.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zhao2021c,

title = {Heavy-Metal-Free Quantum Dot-Based Flexible Electronics},

author = {Tianshuo Zhao and Amrita Basu and Karthik Ramasamy and Nikolay S. Makarov and Hunter McDaniel and Cherie R. Kagan},

url = {https://sid.onlinelibrary.wiley.com/doi/full/10.1002/msid.1258},

year  = {2021},

date = {2021-11-29},

journal = {Information Display},

volume = {37},

number = {6},

pages = {24-32},

abstract = {Applications of flexible electronics typically depend less on high computational power, instead exploiting the advantages of devices with a high degree of deformation that are lightweight, disposable or degradable, and low-cost.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ahn2021,

title = {Ink-Lithography for Property Engineering and Patterning of Nanocrystal Thin Films},

author = {Junhyuk Ahn and Sanghyun Jeon and Ho Kun Woo and Junsung Bang and Yong Min Lee and Steven J. Neuhaus and Woo Seok Lee and Taesung Park and Sang Yeop Lee and Byung Ku Jung and Hyungmok Joh and Mingi Seong and Ji-hyuk Choi and Ho Gyu Yoon and Cherie R. Kagan and Soong Ju Oh},

url = {https://pubs.acs.org/doi/abs/10.1021/acsnano.1c04772},

doi = {10.1021/acsnano.1c04772},

year  = {2021},

date = {2021-09-08},

urldate = {2021-09-08},

journal = {ACS Nano},

abstract = {Next-generation devices and systems require the development and integration of advanced materials, the realization of which inevitably requires two separate processes: property engineering and patterning. Here, we report a one-step, ink-lithography technique to pattern and engineer the properties of thin films of colloidal nanocrystals that exploits their chemically addressable surface. Colloidal nanocrystals are deposited by solution-based methods to form thin films and a local chemical treatment is applied using an ink-printing technique to simultaneously modify (i) the chemical nature of the nanocrystal surface to allow thin-film patterning and (ii) the physical electronic, optical, thermal, and mechanical properties of the nanocrystal thin films. The ink-lithography technique is applied to the library of colloidal nanocrystals to engineer thin films of metals, semiconductors, and insulators on both rigid and flexible substrates and demonstrate their application in high-resolution image replications, anticounterfeit devices, multicolor filters, thin-film transistors and circuits, photoconductors, and wearable multisensors.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}