Article
Nanoscience & Nanotechnology
John C. Peterson, Philippe Guyot-Sionnest
Summary: Mid-infrared HgTe colloidal quantum dot photovoltaic devices previously achieved background-limited infrared photodetection at cryogenic temperatures, but the efficiency decreased from 20 to 1% from 150 to 300 K. The reduced efficiency was not due to the carrier diffusion length, but instead it was caused by the series resistance. By reducing the device size, the room-temperature quantum efficiency reached 10% and 15% for HgTe colloidal quantum dot devices with cutoff wavelengths of 2400 cm-1 (4.2 μm) and 2675 cm-1 (3.7 μm), respectively. These small area devices achieved background-limited photodetection at 150 K and a detectivity above 109 Jones at room temperature with a cutoff wavelength of 2675 cm-1 (3.7 μm).
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Yunxiang Di, Kun Ba, Yan Chen, Xudong Wang, Mingqing Zhang, Xinning Huang, Yi Long, Mengdi Liu, Shukui Zhang, Weiyi Tang, Zhangcheng Huang, Tie Lin, Hong Shen, Xiangjian Meng, Meikang Han, Qi Liu, Jianlu Wang
Summary: A two-dimensional titanium carbide (Ti3C2Tx) MXene film is introduced as an effective transparent conducting electrode in lead sulfide quantum dot photodiodes. Exhibiting exceptional near-infrared transmittance control, interface engineering enhances performance, yielding high detectivity, extensive dynamic response, and notable bandwidth, thereby advancing infrared photodiode technology.
Article
Chemistry, Multidisciplinary
Mingyu Li, Shiwu Chen, Xinzhao Zhao, Kao Xiong, Bo Wang, Usman Ali Shah, Liang Gao, Xinzheng Lan, Jianbing Zhang, Hsien-Yi Hsu, Jiang Tang, Haisheng Song
Summary: Infrared solar cells incorporating PbS colloidal quantum dots show high efficiency and stability under full-spectrum illumination, with novel energy-level aligned ZnO thin film and hybrid ligand passivation strategies boosting the performance. The development of matched charge extraction and QD passivation approaches is expected to advance QD optoelectronics technology.
Article
Chemistry, Multidisciplinary
Yang Liu, Yiyuan Gao, Qian Yang, Gao Xu, Xingyu Zhou, Guozheng Shi, Xingyi Lyu, Hao Wu, Jun Liu, Shiwen Fang, Muhammad Irfan Ullah, Leliang Song, Kunyuan Lu, Muhan Cao, Qiao Zhang, Tao Li, Jianlong Xu, Suidong Wang, Zeke Liu, Wanli Ma
Summary: We achieved a low-cost and scalable synthesis of SWIR PbS quantum dot inks for the first time through an extensive investigation of reaction kinetics. The solar cell based on these PbS SWIR quantum dot inks exhibited a record-high power conversion efficiency of 1.44% with an 1100 nm cutoff silicon filter, and the photodetector device showed a low dark current density of 2x10(-6) A cm(-2) at -0.8 V reverse bias and a high external quantum efficiency of 70% at approximately 1300 nm. Our results realize the direct synthesis of low-cost and scalable SWIR quantum dot inks and may accelerate the industrialization of consumer SWIR technologies.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Sachidananda Krishnamurthy, Ajay Singh, Zhongjian Hu, Anastasia Blake, Younghee Kim, Amita Singh, Ekaterina A. Dolgopolova, Darrick J. Williams, Andrei Piryatinski, Anton Malko, Han Htoon, Milan Sykora, Jennifer A. Hollingsworth
Summary: In this study, PbS/CdS core/shell quantum dots with single-emitter properties were successfully synthesized for room-temperature, solid-state operation in the telecom O and S bands. The research demonstrated the reasons for inhomogeneous broadening and the longer radiative decay times of core/shell structures compared to PbS cores.
Article
Chemistry, Multidisciplinary
Youngmin Lee, Jin Woo Lee, Sejoon Lee, Toshiro Hiramoto, Kang L. Wang
Summary: This study demonstrates reconfigurable multivalue logic functions on an all-around-gate silicon ellipsoidal quantum-dot transistor, with precise self-control of the energetic Coulomb blockade conditions achieved by changing the applied bias voltage. This self-controllability provides a great advantage in choosing multiple operation points and effectively demonstrates weighted data states.
Article
Chemistry, Multidisciplinary
Cong Zhang, Xingtian Yin, Guojiang Qian, Zi Sang, Yawei Yang, Wenxiu Que
Summary: This article presents a solution-phase ligand exchange-based PbS-I quantum-dot-sensitized InGaZnO hybrid phototransistor with excellent air stability and tunable operation mode to meet different detection requirements.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Zhenzhen Ma, Jiahui Li, Yating Zhang, Hongliang Zhao, Qingyan Li, Chengqi Ma, Jianquan Yao
Summary: This study addressed the low sensitivity issue of lead sulfide quantum dots-based photodetectors by introducing a tunneling organic layer and an appropriate thickness of PMMA layer. This led to improved responsivity and detectivity of the device, offering a new solution to the problems traditionally associated with quantum dots-based infrared photodetectors.
Article
Chemistry, Multidisciplinary
Emmanuel K. Ampadu, Jungdong Kim, Eunsoon Oh
Summary: A lateral photovoltaic device was fabricated for infrared to terahertz detection by chemically depositing PbS films on titanium substrates. Material properties of PbS films on glass were discussed, and the device operated at room temperature with a wavelength range up to 50 μm, making it highly applicable in various fields.
Article
Nanoscience & Nanotechnology
Shihab Bin Hafiz, Mohammad M. Al Mahfuz, Dong-Kyun Ko
Summary: The study introduces the first vertical intraband quantum dot heterojunction devices, composed of Ag2Se/PbS/Ag2Se quantum dot stacks, which offer reduced dark conductivity and simplified device fabrication process. The improvement in the colloidal synthesis of Ag2Se quantum dots was discussed, along with analysis of key processes and device performance parameters, leading to a significant increase in mid-wavelength responsivity at room temperature compared to previous generation devices.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Materials Science, Multidisciplinary
Shuo Zhang, Menglu Chen, Ge Mu, Jinmei Li, Qun Hao, Xin Tang
Summary: This paper demonstrates an efficient spray-stencil lithography technique for the scalable fabrication of multichannel HgTe CQD infrared detectors that can respond to different spectral ranges, producing uniform and smooth CQD films on various substrates. The fabricated CQD detectors exhibit high peak D* values in both short-wave and mid-wave regions, with infrared imaging capability down to a low noise equivalent temperature difference.
ADVANCED MATERIALS TECHNOLOGIES
(2022)
Article
Engineering, Electrical & Electronic
Christopher Melnychuk, Philippe Guyot-Sionnest
Summary: In this study, the potential detectivity limits of HgTe nanocrystal quantum dot photodetectors were examined using a microscopic detailed balance model. The results showed that even with fast nonradiative recombination, HgTe quantum dot solids can achieve detectivities close to those of Auger-limited HgCdTe crystals. Furthermore, it was found that by reducing nonradiative recombination, larger detectivity limits can be achieved compared to HgCdTe. These findings are important for the future advancement of infrared photodetection with nanocrystal quantum dots.
JOURNAL OF ELECTRONIC MATERIALS
(2022)
Article
Chemistry, Analytical
Fengqiu Jiang, Yuyu Bu
Summary: This study successfully grew GaN/AlN multi-quantum wells on a sapphire substrate using MBE technology, and the results showed excellent optical response and linearity at room temperature, indicating great potential for research and application in short-wave infrared detection.
Article
Chemistry, Physical
Miguel Albaladejo-Siguan, David Becker-Koch, Elizabeth C. Baird, Yvonne J. Hofstetter, Ben P. Carwithen, Anton Kirch, Sebastian Reineke, Artem A. Bakulin, Fabian Paulus, Yana Vaynzof
Summary: Light-harvesting devices made from lead sulfide quantum dot absorbers have promising applications in third-generation photovoltaics. Passivating the quantum dot surfaces and managing the excess lead halide can improve device performance and stability.
ADVANCED ENERGY MATERIALS
(2022)
Article
Energy & Fuels
Meiying Li, Shuaipu Zang, Yinglin Wang, Jinhuan Li, Jiangang Ma, Xintong Zhang, Yichun Liu
Summary: This study successfully improved the power conversion efficiency of PbS colloidal quantum dot solar cells by preparing a n(+)−n double-layered ZnO electron transport layer.
Article
Physics, Applied
Anthony Aiello, Yuanpeng Wu, Zetian Mi, Pallab Bhattacharya
APPLIED PHYSICS LETTERS
(2020)
Article
Physics, Applied
Kunook Chung, Ayush Pandey, Tuba Sarwar, Anthony Aiello, Zetian Mi, Pallab Bhattacharya, Pei-Cheng Ku
APPLIED PHYSICS LETTERS
(2020)
Review
Chemistry, Analytical
Hemendra Ghimire, P. V. V. Jayaweera, Divya Somvanshi, Yanfeng Lao, A. G. Unil Perera
Article
Optics
Mahitosh Biswas, Ravinder Kumar, Arka Chatterjee, Yuanpeng Wu, Zetain Mi, Pallab Bhattacharya, Samir Kumar Pal, Subhananda Chakrabarti
JOURNAL OF LUMINESCENCE
(2020)
Article
Nanoscience & Nanotechnology
Ankit Udai, Anthony Aiello, Tarni Aggarwal, Dipankar Saha, Pallab Bhattacharya
Summary: This study investigated the femtosecond carrier and photon dynamics in self-organized In0.27Ga0.73N/GaN QDs grown by molecular beam epitaxy. The unique phenomenon in the dynamics is attributed to the contrast in carrier density caused by the different effective masses of carriers.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Physics, Condensed Matter
Tarni Aggarwal, Ankit Udai, Debashree Banerjee, Vikas Pendem, Shonal Chouksey, Pratim Saha, Sandeep Sankaranarayanan, Swaroop Ganguly, Pallab Bhattacharya, Dipankar Saha
Summary: The ultrafast nonlinear carrier-photon dynamics of GaN-based optoelectronic devices with nanostructures are studied, focusing on the impact of excited-state dynamics on device performance. Experimental and theoretical research shows the importance of understanding carrier and photon dynamics in these nanostructures.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2021)
Article
Nanoscience & Nanotechnology
Tarni Aggarwal, Ankit Udai, Pratim K. Saha, Swaroop Ganguly, Pallab Bhattacharya, Dipankar Saha
Summary: Efficiency droop at high carrier-injection regimes is a concern in InGaN/GaN quantum-confined hetero-structure-based light-emitting diodes (LEDs). This study demonstrates a potential solution through the positive effects from an optical cavity in suppressing the Auger recombination rate and highlights its technological importance.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Analytical
Araghni Bhattacharya, Satyajit Mahata, Ashutosh Bandyopadhyay, Biman B. Mandal, Vadivelu Manivannan
Summary: The molecule 2,4,5-tris(2-pyridyl)imidazole (L) has been evaluated as a probe for dual sensing of Hg2+ and Cu2+ ions. It shows a sensitive and selective response in the presence of both ions and can detect them in specific pH ranges. The probe's detection limit for Cu2+ is below the allowable limit prescribed by the United States Environmental Protection Agency. Experimental observations are supported by calculations and cell imaging studies.
Article
Nanoscience & Nanotechnology
Ankit Udai, Swaroop Ganguly, Pallab Bhattacharya, Dipankar Saha
Summary: This study investigates the ultrafast carrier dynamics of bound states in In0.14Ga0.86N/GaN quantum wells using femtosecond transient absorption spectroscopy. It reveals that both the ground and excited states contribute to the overall dynamics, which can be decoupled in the absorption spectra and time-resolved dynamics.
Article
Nanoscience & Nanotechnology
Fu-Chen Hsiao, Arnab Hazari, Yia-Chung Chang, Pallab Bhattacharya, John M. Dallesasse
Summary: This study presents a comprehensive theoretical modeling of photocurrent spectra generated by an In0.91Ga0.09N/ In0.4Ga0.6N disk-in-wire photodiode. The calculated photocurrent spectra show good agreement with experimental data, and the physical mechanisms for the observed prominent peaks are identified and investigated.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2022)
Article
Physics, Applied
Yuanpeng Wu, Ping Wang, Woncheol Lee, Anthony Aiello, Parag Deotare, Theodore Norris, Pallab Bhattacharya, Mackillo Kira, Emmanouil Kioupakis, Zetian Mi
Summary: Both 2D TMDs and III-V semiconductors are potential platforms for quantum technology, but each with its limitations. 2D TMDs have a large exciton binding energy and customizable quantum properties, but compatibility issues with existing industrial processes. On the other hand, III-nitrides have been widely used in light-emitting devices and power electronics but lack exploitation of excitonic quantum aspects. Recent advancements in 2D III-nitrides have shown promise in achieving room-temperature quantum technologies.
APPLIED PHYSICS LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Anthony Aiello, Debabrata Das, Pallab Bhattacharya
Summary: In this study, InGaN/GaN quantum dot light-emitting diodes were demonstrated on silicon substrates with a planar buffer layer formed by coalescing GaN nanowires. The devices showed strong electroluminescence with a minimal blue shift and a polarization field. However, efficiency droop was observed beyond an injection of 40A/cm(2), possibly due to defect-assisted Auger recombination and carrier leakage from the active region.
ACS APPLIED NANO MATERIALS
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Kunook Chung, Ayush Pandey, Tuba Sarwar, Anthony Aiello, Zetian Mi, Pallab Bhattacharya, Pei-Cheng Ku
2020 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)
(2020)
Proceedings Paper
Engineering, Electrical & Electronic
A. Pandey, A. Aiello, J. Gim, R. Hovden, E. Kioupakis, P. Bhattacharya, Z. Mi
2020 IEEE PHOTONICS CONFERENCE (IPC)
(2020)
Article
Engineering, Electrical & Electronic
Debabrata Das, Anthony Aiello, Wei Guo, Pallab Bhattacharya
IEEE TRANSACTIONS ON NANOTECHNOLOGY
(2020)
Article
Engineering, Electrical & Electronic
Tonghui Li, Xiaofeng Duan, Kai Liu, Yongqing Huang
Summary: This paper proposes a hybrid genetic algorithm (HGA) to simplify the process of photodiode parameter extraction and compares its performance with other optimization algorithms. The results show that HGA has better performance in parameter fitting, convergence speed, and accuracy.
MICROELECTRONICS JOURNAL
(2024)
Article
Engineering, Electrical & Electronic
Prachuryya Subash Das, Deepjyoti Deb, Rupam Goswami, Santanu Sharma, Rajesh Saha
Summary: This article proposes the investigation of low power performance of a fin field-effect transistor (FinFET) with surrounding gates using a calibrated technology computer-aided design (TCAD) framework. The study explores the impact of core dimensions and gate edge suppression on the electrical parameters of the device. It is found that reducing the channel length by 35% improves the overall low power performance of the FinFET.
MICROELECTRONICS JOURNAL
(2024)
