Publications
Publications
2026
Detector having quantum dot pn junction photodiode
US Patent 12,523,748
2024
Advanced Functional Materials 34 (39), 2405307
A comprehensive review of the development of HgTe colloidal quantum dots for infrared optoelectronics, covering advances in synthesis, surface chemistry, device architecture, and the path toward room-temperature MWIR imaging.
2021
Small 17 (25), 2101166
A rapid in situ ligand-exchange approach enables the formation of ordered 3D PbSe nanocrystal superlattices for use as SWIR photodetectors, combining structural order with improved carrier transport.
2020
IEEE Spectrum 57 (3), 24–29
An invited feature article for IEEE Spectrum covering the commercialization trajectory of colloidal quantum dot image sensors, the technical case for replacing CMOS sensors in SWIR/MWIR cameras, and the remaining challenges in device integration and manufacturability.
2019
Mid-infrared photodetectors
US Patent 10,290,753
2017
ACS Applied Materials & Interfaces 9 (41), 36173–36180
Self-doped HgSe colloidal quantum dots are used as a model system to examine how electronic and optical properties evolve as quantum confinement vanishes, providing insight into the crossover between nanocrystal and bulk-like behavior relevant to intraband IR absorbers.
Nano Letters 17 (7), 4067–4074
Colloidal HgTe nanoplatelets are characterized as two-dimensional quantum wells, revealing their charge transport and photoresponse behavior and establishing a framework for understanding 2D mercury chalcogenide optoelectronics.
2016
Journal of the American Chemical Society 138 (33), 10496–10501
HgTe nanoplatelets with strong 2D quantum confinement are synthesized and shown to emit narrow near-infrared photoluminescence, a result of atomically precise thickness control in this zero-bandgap material system.
Mid-infrared photodetectors
US Patent 9,318,628
2015
Nano Letters 15 (4), 2285–2290
The synthesis and structural characterization of silicon telluride (Si₂Te₃) as a new silicon-based 2D chalcogenide. Nanoribbons and nanoplates are grown and their optical and structural properties investigated, expanding the 2D materials library beyond transition metal dichalcogenides.
2014
ACS Nano 8 (8), 8676–8682
Theoretical calculations of the electronic structure of HgTe CQDs are combined with experimental spectroscopy to establish a comprehensive size-to-wavelength map from SWIR through LWIR. Photocurrent detection is demonstrated up to 12 μm — the longest wavelength reported for a colloidal material at that time.
The Journal of Physical Chemistry Letters 5 (7), 1139–1143
HgS colloidal quantum dots are shown to exhibit stable n-type doping in air through a surface chemistry approach, enabling intraband optical transitions and demonstrating the potential for self-doped mercury chalcogenide nanocrystals in mid-IR applications.
The Journal of Physical Chemistry C 118 (5), 2749–2753
Mid-infrared photoluminescence is characterized for a size series of HgTe CQDs, establishing quantum yield behavior and size-dependent emission linewidths across the MWIR atmospheric window, supporting the case for CQD-based mid-IR emitters.
2013
Chemistry of Materials 25 (8), 1272–1282
An invited review covering synthesis, optical properties, charge transport, and device performance of mercury chalcogenide colloidal quantum dots for mid-infrared detection. Provides a framework for understanding the tradeoffs between material quality and detector performance in the MWIR.
Advanced Materials 25 (1), 137–141
HgTe CQDs in an inorganic As₂S₃ matrix achieve carrier mobilities 100× higher than organic-capped films while remaining intrinsic. FET measurements reveal temperature-dependent transport, and MWIR photoconductors reach a detectivity of 3.5 × 10¹⁰ Jones at 230 K.
Infrared Physics & Technology 59, 133–136
A concise invited review summarizing the state of colloidal HgTe quantum dot technology for mid-infrared photodetection, covering synthesis approaches, detector fabrication, and performance benchmarks relative to conventional epitaxial IR detector materials.
2012
Journal of Electronic Materials 41 (10), 2725–2729
A materials-focused study correlating synthesis conditions and ligand treatments with photoconductive performance of HgTe CQD films across the 3–5 μm atmospheric window, targeting low-cost MWIR detection.
Nanotechnology 23 (17), 175705
A systematic optical study of HgTe CQD size series mapping absorption edge positions, exciton features, and Stokes shifts from SWIR through MWIR. Establishes the optical database used to guide synthesis for targeted cutoff wavelengths.
The Journal of Physical Chemistry C 116 (1), 1344–1349
Electrochemical doping reversibly switches HgTe CQD films between n- and p-type conduction, enabling characterization of carrier-type-dependent transport and photoresponse. This bipolar doping control is a key capability for future CQD diode architectures.
Proc. SPIE 8271, 827109
Carrier transport and thermal noise properties of HgTe CQD films are investigated across a range of temperatures and ligand treatments, providing the device-physics foundation needed to understand and improve detectivity in colloidal MWIR photoconductors.
2011
Nature Photonics 5 (8), 489–493
The first demonstration of room-temperature colloidal quantum dot photodetectors operating beyond 5 μm — at that time the longest interband absorption wavelength reported for any colloidal material. HgTe CQD films drop-cast onto electrodes exhibit photoresponse across the 3–5 μm atmospheric transparency window.
Journal of the American Chemical Society 133 (41), 16422–16424
An improved two-step hot-injection synthesis yields HgTe CQDs with narrow size distributions and sharp excitonic features tunable between 1.3 and 5 μm. Narrow photoluminescence and well-resolved photodetection spectra establish HgTe CQDs as a versatile platform for near- and mid-IR optoelectronics.
Journal of Applied Physics 110 (3), 033110
Temperature-dependent photoconductive measurements reveal the thermal activation behavior of dark current and the noise mechanisms that set the detectivity limit at room temperature, establishing the thermal budget for MWIR CQD detector operation.
2010
Journal of Chemical Education 87 (12), 1403–1407
A low-cost method for measuring liquid contact angles using a standard digital camera and open-source image analysis, enabling quantitative surface energy measurements without specialized goniometry equipment for undergraduate laboratory instruction.