Cherie R Kagan Research Group

@article{nokey,

title = {Nanodiamond emulsions for enhanced quantum sensing and click-chemistry conjugation},

author = {Henry J. Shulevitz and Ahmad Amirshaghaghi and Mathieu Ouellet and Caroline Brustoloni and Shengsong Yang and Jonah J. Ng and Tzu-Yung Huang and Davit Jishkariani and Christopher B. Murray and Andrew Tsourkas and Cherie R. Kagan and Lee C. Bassett},

url = {https://arxiv.org/abs/2311.16530},

doi = {10.48550/arXiv.2311.16530},

year  = {2023},

date = {2023-12-04},

urldate = {2023-12-04},

abstract = {Nanodiamonds containing nitrogen-vacancy (NV) centers can serve as colloidal quantum sensors of local fields in biological and chemical environments. However, nanodiamond surfaces are challenging to modify without degrading their colloidal stability or the NV center's optical and spin properties. Here, we report a simple and general method to coat nanodiamonds with a thin emulsion layer that preserves their quantum features, enhances their colloidal stability, and provides functional groups for subsequent crosslinking and click-chemistry conjugation reactions. To demonstrate this technique, we decorate the nanodiamonds with combinations of carboxyl- and azide-terminated amphiphiles that enable conjugation using two different strategies. We study the effect of the emulsion layer on the NV center's spin lifetime, and we quantify the nanodiamonds' chemical sensitivity to paramagnetic ions using T1 relaxometry. This general approach to nanodiamond surface functionalization will enable advances in quantum nanomedicine and biological sensing.},

keywords = {},

pubstate = {forthcoming},

tppubtype = {article}

}

@article{Choi2023b,

title = {Thermally Reconfigurable, 3D Chiral Optical Metamaterials: Building with Colloidal Nanoparticle Assemblies},

author = {Yun Chang Choi and Shengsong Yang and Christopher B. Murray and Cherie R. Kagan},

url = {https://pubs.acs.org/doi/full/10.1021/acsnano.3c06757},

doi = {10.1021/acsnano.3c06757},

year  = {2023},

date = {2023-11-13},

journal = {ACS Nano},

volume = {17},

issue = {22},

pages = {22611–22619},

abstract = {The three-dimensional, geometric handedness of chiral optical metamaterials allows for the rotation of linearly polarized light and creates a differential interaction with right and left circularly polarized light, known as circular dichroism. These three-dimensional metamaterials enable polarization control of optical and spin excitation and detection, and their stimuli-responsive, dynamic switching widens applications in chiral molecular sensing and imaging and spintronics; however, there are few reconfigurable solid-state implementations. Here, we report all-solid-state, thermally reconfigurable chiroptical metamaterials composed of arrays of three-dimensional nanoparticle/metal bilayer heterostructures fabricated from coassemblies of phase change VO2 and metallic Au colloidal nanoparticles and thin films of Ni. These metamaterials show dynamic switching in the mid-infrared as VO2 is thermally cycled through an insulator–metal phase transition. The spectral range of operation is tailored in breadth by controlling the periodicity of the arrays and thus the hybridization of optical modes and in position through the mixing of VO2 and Au nanoparticles.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marino2023,

title = {Crystallization of binary nanocrystal superlattices and the relevance of short-range attraction},

author = {Emanuele Marino and R. Allen LaCour and Timothy C. Moore and Sjoerd W. van Dongen and Austin W. Keller and Di An and Shengsong Yang and Daniel J. Rosen and Guillaume Gouget and Esther H. R. Tsai and Cherie R. Kagan and Thomas E. Kodger and Sharon C. Glotzer and Christopher B. Murray },

url = {https://doi.org/10.1038/s44160-023-00407-2},

doi = {10.1038/s44160-023-00407-2},

year  = {2023},

date = {2023-10-12},

journal = {Nature Synthesis},

abstract = {The synthesis of binary nanocrystal superlattices (BNSLs) enables the targeted integration of orthogonal physical properties, such as photoluminescence and magnetism, into a single superstructure, unlocking a vast design space for multifunctional materials. However, the formation mechanism of BNSLs remains poorly understood, restricting the prediction of the structure and properties of superlattices. Here we use a combination of in situ scattering and molecular simulation to elucidate the self-assembly of two common BNSLs (AlB2 and NaZn13) through emulsion templating. Our self-assembly experiments reveal that no intermediate structures precede the formation of the final binary phases, indicating that their formation proceeds through classical nucleation. Using simulations, we find that, despite the formation of AlB2 and NaZn13 typically being attributed to entropy, their self-assembly is most consistent with the nanocrystals possessing short-range interparticle attraction, which we find can accelerate nucleation kinetics in BNSLs. We also find homogeneous, classical nucleation in simulations, corroborating our experiments. These results establish a robust correspondence between experiment and theory, paving the way towards prediction of BNSLs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mallavarapu2023,

title = {TiO2 Metasurfaces with Visible Quasi-Guided Mode Resonances via Direct Imprinting of Aqueous Nanocrystal Dispersions},

author = {Akhila Mallavarapu and Chavez FK Lawrence and Brian Huang and Bryan O Torres Maldonado and Paulo Arratia and Cherie R Kagan},

url = {https://pubs.acs.org/doi/abs/10.1021/acsanm.3c03507},

doi = {10.1021/acsanm.3c03507},

year  = {2023},

date = {2023-09-07},

journal = {ACS Applied Nano Materials},

abstract = {We report a room temperature, environmentally benign, water-based, single-step direct nanoimprint process to pattern dielectric metasurfaces using aqueous titanium dioxide (TiO2) nanocrystal (NC) inks, which are free of polymer additives or nonaqueous solvents typically used in nanofabrication. The metasurfaces are composed of TiO2 NC structures with a high refractive index of 1.94 ± 0.02 at 543 nm. TiO2 NC metasurfaces are designed to resonate at visible wavelengths and are fabricated as two-dimensional nanopillar gratings atop waveguides. Guided mode resonances within the waveguide couple to the overlaying gratings and scatter into free space, forming high quality (Q) factor quasi-guided mode (QGM) resonances. Electric and magnetic QGM resonances are observed, and their environmental refractive index sensitivities (S) are measured to be 69.1 and 70.4 nm/RIU, respectively, with a figure of merit (FOM) = Q × S > 3000. The use of water-based inks and the room temperature processing allow integration of TiO2 NC metasurfaces on rigid and flexible, polymeric substrates.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Lynch2023,

title = {Gate-Tunable Optical Anisotropy in Wafer-Scale, Aligned Carbon Nanotube Films},

author = {Jason Lynch and Evan Smith and Adam Alfieri and Baokun Song and Cindy Yueli Chen and Chavez Lawrence and Cherie Kagan and Honggang Gu and Shiyuan Liu and Lian-Mao Peng and Shivashankar Vangala and Joshua R. Hendrickson and Deep Jariwala},

url = {https://arxiv.org/abs/2304.08337},

year  = {2023},

date = {2023-08-03},

abstract = {Telecommunications and polarimetry both require the active control of the polarization of light, Currently, this is done by combining intrinsically anisotropic materials with tunable isotropic materials into heterostructures using complicated fabrication techniques due to the lack of scalable materials that possess both properties. Tunable birefringent and dichromic materials are scarce and rarely available in high-quality thin films over wafer scales. In this paper, we report semiconducting, highly aligned, single-walled carbon nanotubes (SWCNTs) over 4" wafers with normalized birefringence and dichroism values 0.09 and 0.58, respectively. The real and imaginary parts of the refractive index of the SWCNT films are tuned by up to 5.9% and 14.3% in the infrared at 2200 nm and 1660 nm, respectively, using electrostatic doping. Our results suggest that aligned SWCNTs are among the most anisotropic and tunable optical materials known and opens new avenues for their application in integrated photonics and telecommunications.},

keywords = {},

pubstate = {forthcoming},

tppubtype = {article}

}