Article
Chemistry, Physical
Piotr Andrzej Wronski, Pawel Wyborski, Anna Musial, Pawel Podemski, Grzegorz Sek, Sven Hoefling, Fauzia Jabeen
Summary: This study demonstrates single-photon emission with a low probability of multiphoton events of 5% in the C-band of telecommunication spectral range using InAs quantum dots. By implementing a specially designed buffer layer and reflector, the extraction efficiency of QD emission is enhanced, with a determined emission rate limit of 0.5 GHz. The proposed technology platform is proven to be relevant for achieving non-classical light sources in fiber-based quantum communication applications.
Article
Nanoscience & Nanotechnology
Pawel Holewa, Shima Kadkhodazadeh, Michal Gawelczyk, Pawel Baluta, Anna Musial, Vladimir G. Dubrovskii, Marcin Syperek, Elizaveta Semenova
Summary: The development of quantum communication technology requires quantum emitters that can generate single photons and entangled photon pairs. This study successfully synthesized low surface density InAs x P1-x quantum dots with symmetric profiles using droplet epitaxy, which can contribute to the fabrication of versatile quantum emitters.
Article
Chemistry, Multidisciplinary
Maxim Rakhlin, Grigorii Klimko, Sergey Sorokin, Marina Kulagina, Yurii Zadiranov, Dmitrii Kazanov, Tatiana Shubina, Sergey Ivanov, Alexey Toropov
Summary: This paper reports on single-photon emitters designed for the telecommunication O-band. These emitters consist of InAs/(In)GaAs quantum dots with asymmetric barriers placed inside semiconductor tapered nanocolumns acting as photonic nanoantennas. The implemented design allows for a shift in the quantum dot radiation wavelength towards the O-band, and the nanoantennas collect and effectively output the radiation. With non-resonant optical pumping, the average count rate of emitted single photons exceeds 10 MHz, with a second-order correlation function g((2))(0) = 0.18 at 8 K.
Article
Chemistry, Multidisciplinary
Dan Dalacu, Philip J. Poole, Robin L. Williams
Summary: The geometry of nanowires plays a crucial role in determining the rate of photon generation and efficiency of photon collection in non-classical light sources. By embedding quantum dots in nanowires with tailored geometries, high efficiency single photon generation with minimal multi-photon emissions can be achieved.
Article
Chemistry, Multidisciplinary
Yalian Weng, Guixiong Chen, Junyang Nie, Sihua Que, Suk-Ho Song, Yongshen Yu, Fan Zhang, Hengshan Liu, Xiongtu Zhou, Yongai Zhang, Jie Sun, Jang-Kun Song, Chaoxing Wu, Tailiang Guo, Qun Yan
Summary: This work proposed a novel hybrid device of organic LEDs and inorganic blue GaN LEDs, which can achieve full white and other colors. By applying timing variable opposite voltages, the hybrid device can independently control the emission from blue LEDs or stacked OLEDs to form mixed colors. It has a high color gamut and color rendering index, indicating potential applications in smart solid-state lighting, display, and light communication.
Article
Optics
Kazuhiro Kuruma, Hironobu Yoshimi, Yasutomo Ota, Ryota Katsumi, Masahiro Kakuda, Yasuhiko Arakawa, Satoshi Iwamoto
Summary: This study reports single-photon sources using single quantum dots embedded in topological slow light waveguides based on valley photonic crystals. The experiment demonstrates Purcell-enhanced single-photon emission in a topological slow light mode with a group index over 20, showing robust propagation even under sharp bends.
LASER & PHOTONICS REVIEWS
(2022)
Article
Chemistry, Multidisciplinary
Yulong An, Xu Lin, Yuxi Zhou, Yan Li, Yunwu Zheng, Chunhua Wu, Kaimeng Xu, Xijuan Chai, Can Liu
Summary: Red, green, and blue carbon dots (RGB CDs) were successfully synthesized with stable optical properties and significant photoluminescence characteristics. A white fluorescent CD solution was prepared by mixing these multicolor fluorescent CDs in appropriate proportions.
Article
Chemistry, Multidisciplinary
Chenglian Zhu, Malwina Marczak, Leon Feld, Simon C. Boehme, Caterina Bernasconi, Anastasiia Moskalenko, Ihor Cherniukh, Dmitry Dirin, Maryna Bodnarchuk, Maksym Kovalenko, Gabriele Raino
Summary: Attaining pure single-photon emission is crucial for quantum technologies. Over the past 20 years, researchers have developed various solid-state quantum emitters, but most of them require complex techniques. However, using quantum emitters that can operate at room temperature can greatly reduce system complexity.
Article
Nanoscience & Nanotechnology
Ali Issa, Tiziana Ritacco, Dandan Ge, Aurelie Broussier, Giuseppe Emanuele Lio, Michele Giocondo, Sylvain Blaize, Tien Hoa Nguyen, Xuan Quyen Dinh, Christophe Couteau, Renaud Bachelot, Safi Jradi
Summary: This paper presents a new strategy to obtain homogeneous dispersion of grafted quantum dots (QDs) in a photopolymer matrix and their integration into single-photon sources by two-photon polymerization (TPP). The method involves phase transfer of QDs from organic solvents to an acrylic matrix through ligand exchange. The results show that the QDs can be dispersed in the photopolymer without clustering and maintain their photoluminescence spectra for a long time. The ability of the hybrid photopolymer to create micro- and nanostructures by TPP is demonstrated, and the integration of a single-photon source is confirmed by auto-correlation measurements.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Crystallography
M. Zimmer, A. Trachtmann, M. Jetter, P. Michler
Summary: Low areal density InGaAs quantum dots suitable for single-photon applications are fabricated on a GaAs substrate by MOVPE. AFM measurements reveal a low QD density of 3.2 x 10^7 cm(-2) for a high V/III ratio of 360. The InGaAs QDs are embedded into a pin-LED structure with an oxide aperture for targeted electrical excitation. Low temperature electroluminescence measurements confirm the electrical excitation of a single QD.
JOURNAL OF CRYSTAL GROWTH
(2023)
Article
Chemistry, Physical
Ho-Kyung Lee, Ye-Jun Ban, Hyun-Jong Lee, Ji-Hyeon Kim, Sang-Joon Park
Summary: In this paper, a new blue-emitting material called CuCrS2/ZnS QDs (CCS QDs) was introduced. The CCS QDs were prepared in a core/shell structure through a one-pot synthesis using 1-dodecanethiol as a sulfur source and co-ligand. The CCS QDs exhibited a semi-spherical colloidal nanocrystalline shape with an average diameter of 9.0 nm and ZnS shell thickness of 1.6 nm. The PL max was observed at 465 nm with an excitation wavelength of 400 nm and PLQY was 5% at an initial [Cr3+]/[Cu+] molar ratio of one in the core synthesis. With an increase in the initial molar ratio, the CCS QDs showed slightly blue-shifted PL emission spectra and increased PLQY, reaching a maximum of 10% at a molar ratio of 2.0 (462 nm PL max). However, when the initial molar ratio exceeded two, non-emissive Cr2S3 nanoflakes formed, resulting in a lower photoluminescence quantum yield of 4.5% with a PL max of 461 nm at a molar ratio of four.
Article
Physics, Applied
Adrien Khalili, Claire Abadie, Tung Huu Dang, Audrey Chu, Eva Izquierdo, Corentin Dabard, Charlie Greboval, Mariarosa Cavallo, Huichen Zhang, Stefano Pierini, Yoann Prado, Xiang Zhen Xu, Sandrine Ithurria, Gregory Vincent, Christophe Coinon, Ludovic Desplanque, Emmanuel Lhuillier
Summary: This study proposes a method to broaden the spectral range of InGaAs by using HgTe nanocrystals and alleviating lattice matching constraints in short wave infrared sensing. A diode structure is designed, where a p-type HgTe NC array and n-type InGaAs wires are used to extract minority carriers. This work opens up new possibilities for infrared detection using epitaxially grown and colloidally grown semiconductors.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Jingtao Liu, Hang Li, Xiaohui Liu, Ying Wang, Yingnan Guo, Shufang Wang, Guangsheng Fu, Yuriy I. Mazur, Morgan E. Ware, Gregory J. Salamo, Baolai Liang
Summary: This study investigates carrier injection hybrid structures, where carriers are injected from an adjacent quantum well into a layer of surface quantum dots. The hybrid structures show enhanced photoluminescence intensity compared to reference surface quantum dots. The best carrier injection efficiency is achieved with a 2.5 nm spacer, demonstrating strong coupling between the quantum well and the surface quantum dots. However, the carrier injection is less efficient than expected due to resonant carrier tunneling and significant carrier loss through nonradiative recombination.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Sascha Kolatschek, Cornelius Nawrath, Stephanie Bauer, Jiasheng Huang, Julius Fischer, Robert Sittig, Michael Jetter, Simone Luca Portalupi, Peter Michler
Summary: The combination of semiconductor quantum dots with photonic cavities has shown promising results in achieving nonclassical light sources with high brightness, indistinguishability, and repetition rate. By coupling InGaAs/GaAs QDs to a circular Bragg grating cavity, enhancements in geometric extraction efficiency and brightness have been demonstrated under different excitation conditions. Through p-shell pumping, high count rates with pure single-photon emission have been achieved, along with good single-photon purity at temperatures of up to 77 K.
Article
Optics
Xiang You, Ming-Yang Zheng, Si Chen, Run-Ze Liu, Jian Qin, Mo-Chi Xu, Zheng-Xuan Ge, Tung-Hsun Chung, Yu-Kun Qiao, Yang-Fan Jiang, Han-Sen Zhong, Ming-Cheng Chen, Hui Wang, Yu-Ming He, Xiu-Ping Xie, Hao Li, Li-Xing You, Christian Schneider, Juan Yin, Teng-Yun Chen, Mohamed Benyoucef, Yong-Heng Huo, Sven Hoefling, Qiang Zhang, Chao-Yang Lu, Jian-Wei Pan
Summary: This study reports quantum interference between two single photons from independent semiconductor quantum dots (QDs) separated by a 302 km optical fiber, representing a key step towards long-distance solid-state quantum networks.
ADVANCED PHOTONICS
(2022)
Article
Optics
Moritz Pfluger, Daniel Brunner, Tobias Heuser, James A. Lott, Stephan Reitzenstein, Ingo Fischer
Summary: In this article, we demonstrate the construction of the largest network of optically coupled semiconductor lasers reported so far by using diffractive optics in an external cavity to couple vertical-cavity surface-emitting lasers (VCSELs). We successfully align and lock 22 out of 25 lasers to an external drive laser, and show significant interaction between the lasers of the array. Our VCSEL network, with its high homogeneity, strong interaction, and scalability, serves as a promising platform for experimental investigations of complex systems and has direct applications as a photonic neural network.
Article
Optics
Pawel Mrowinski, Pawel Holewa, Aurimas Sakanas, Grzegorz Sek, Elizaveta Semenova, Marcin Syperek
Summary: We conducted comprehensive numerical studies on a hybrid III-V/Si-based waveguide system, which enables efficient light coupling between an integrated III-V quantum dot emitter and an on-chip quantum photonic integrated circuit on a silicon substrate. Our proposed platform consists of a hybrid InP/Si waveguide and an InP-embedded InAs quantum dot, operating at a wavelength of 1550 nm in the telecom C-band. The numerical studies revealed high optical field transfer efficiency between the InP/Si and Si waveguides, directional dipole emission to the hybrid InP/Si waveguide, and off-chip outcoupling efficiency along the Si waveguide.
Article
Physics, Applied
Ching-Wen Shih, Imad Limame, Sebastian Krueger, Chirag C. Palekar, Aris Koulas-Simos, Daniel Brunner, Stephan Reitzenstein
Summary: In this study, optically pumped micropillar lasers with low-absorbing Al0.2Ga0.8As/Al0.9Ga0.1As dielectric Bragg reflectors were designed and characterized. The incorporation of 20% Al content in the DBRs significantly improved the pump efficiency by creating an optical pumping window from 700 to 820 nm. Experimental observations also showed that pump laser wavelengths outside of the specific range resulted in reduced pump efficiency.
APPLIED PHYSICS LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Daniel Wigger, Johannes Schall, Marielle Deconinck, Nikolai Bart, Pawel Mrowinski, Mateusz Krzykowski, Krzysztof Gawarecki, Martin von Helversen, Ronny Schmidt, Lucas Bremer, Frederik Bopp, Dirk Reuter, Andreas D. Wieck, Sven Rodt, Julien Renard, Gilles Nogues, Arne Ludwig, Pawel Machnikowski, Jonathan J. Finley, Stephan Reitzenstein, Jacek Kasprzak
Summary: Semiconductor quantum dot molecules are versatile in their tunability of optical properties and their ability to cover different energy scales associated with charge and spin physics, making them promising for quantum technological applications. This study demonstrates the coherent control of interdot tunnel-coupling in these systems, focusing on the quantum coherence of optically active trion transitions. By using ultrafast four-wave mixing spectroscopy, a quantum coherence is generated in one trion complex and transferred and probed in another trion configuration, with theoretical modeling providing an explanation of the underlying coupling mechanism and dynamic processes.
Article
Physics, Applied
Chirag Chandrakant Palekar, Manan Shah, Stephan Reitzenstein, Arash Rahimi-Iman
Summary: This study reports the design, nanofabrication, and characterization of high-quality polymer-based micromirror structures using the 3D two-photon polymerization lithography technique. The innovative concept provides microstructures for fast prototyping and offers cost-effective and environmentally sensitive polymer-based mirrors compatible with a wide range of wavelengths. The research demonstrates reproducible and mechanically stable 3D printed micromirrors that enable hybrid nanophotonic devices based on quantum dots, molecules, or 2D quantum materials.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Michael Seidel, Yuhui Yang, Thorsten Schumacher, Yongheng Huo, Saimon Filipe Covre da Silva, Sven Rodt, Armando Rastelli, Stephan Reitzenstein, Markus Lippitz
Summary: Reliable single-photon sources, high coupling efficiency, and low propagation losses are key requirements for quantum plasmonic nanocircuits. The best overall performance of these nanocircuits is achieved by adding a spacer layer between the quantum dot and the plasmonic waveguide, resulting in an improved coupling efficiency through standing wave interference.
Article
Optics
Zaijun Chen, Alexander Sludds, Ronald Davis III, Ian Christen, Liane Bernstein, Lamia Ateshian, Tobias Heuser, Niels Heermeier, James A. Lott, Stephan Reitzenstein, Ryan Hamerly, Dirk Englund
Summary: Researchers demonstrate an optical computing architecture using micrometre-scale VCSEL transmitter arrays, achieving an energy efficiency of 7 fJ per operation and a compute density of 6 tera-operations mm(-2) s(-1). This system overcomes the challenges of ONNs, such as high energy consumption, low compute density, and long latency, providing a new way to accelerate machine learning tasks.
Article
Physics, Multidisciplinary
Yanqiang Guo, Jianfei Zhang, Xiaomin Guo, Stephan Reitzenstein, Liantuan Xiao
Summary: The emission characteristics of quantum-dot micropillar lasers (QDMLs) lie at the intersection of nanophotonics and nonlinear dynamics, providing an ideal platform for studying the optical interface between classical and quantum systems. In this research, a noise-induced bimodal QDML with orthogonal dual-mode outputs is modeled, and the nonlinear dynamics, stochastic mode jumping, and quantum statistics are investigated. The results show that noise-induced effects lead to the emergence of two intensity bifurcation points for the strong and weak modes, and the maximum output power of the strong mode increases with the noise intensity. The anti-correlation of the two modes reaches its maximum at the second intensity bifurcation point. The dual-mode stochastic jumping frequency and effective bandwidth can exceed 100 GHz and 30 GHz under the noise-induced effect. Photon bunching (g((2))(0) > 1) of both modes is observed over a wide range of noise intensities and injection currents. The photon number distribution of the strong or weak mode becomes a mixture of Bose-Einstein and Poisson distributions, with the proportion of the Poisson distribution increasing in the high injection current region for the strong mode and decreasing for the weak mode.
NEW JOURNAL OF PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Maciej Jaworski, Aleksandra Chudzynska, Pawel Mrowinski, Joanna Prazmowska-Czajka, Wojciech Kijaszek, Jan Grosse, Sven Rodt, Stephan Reitzenstein, Grzegorz Sek
Summary: This study proposes the xenon-plasma FIB technology as an alternative solution for the fabrication of photonic microstructures. By optimizing the processing method, GaAs-based photonic microstructures with InGaAs QDs emitting bright light were successfully fabricated.
OPTICAL MATERIALS EXPRESS
(2023)
Article
Materials Science, Multidisciplinary
Martin von Helversen, Lara Greten, Imad Limame, Ching-Wen Shih, Paul Schlaugat, Carlos Anton-Solanas, Christian Schneider, Barbara Rosa, Andreas Knorr, Stephan Reitzenstein
Summary: This study explores the emission properties of quantum emitters in a WSe2 monolayer induced by metallic nanoparticles, and verifies their single-photon purity. The temperature-dependent coherence time and decay time are determined through Michelson interferometry and time-resolved photoluminescence experiments.
Article
Chemistry, Multidisciplinary
Frederico B. Sousa, Raul Perea-Causin, Sean Hartmann, Lucas Lafeta, Barbara Rosa, Samuel Brem, Chirag Palekar, Stephan Reitzenstein, Achim Hartschuh, Ermin Malic, Leandro M. Malard
Summary: The transition metal dichalcogenide family of semiconducting two-dimensional materials has shown great potential in studying the exciton Mott transition. Pulsed laser excitation at high pump fluences can induce the transition to an electron-hole plasma in these materials, leading to a broadband light emission. Correlation measurements reveal the dynamics of electronic cooling, providing insights for further studies and applications in nanolasers and optoelectronic devices.
Article
Materials Science, Multidisciplinary
Frederik Bopp, Johannes Schall, Nikolai Bart, Florian Voegl, Charlotte Cullip, Friedrich Sbresny, Katarina Boos, Christopher Thalacker, Michelle Lienhart, Sven Rodt, Dirk Reuter, Arne Ludwig, Andreas D. Wieck, Stephan Reitzenstein, Kai Mueller, Jonathan J. Finley
Summary: Quantum dot molecules (QDMs) are capable of generating one-and two-dimensional photonic graph states deterministically. In this study, power-dependent Rabi oscillations of direct excitons, spatially indirect excitons, and excitons with a hybridized electron wave function are demonstrated. An off-resonant detection technique based on phonon-mediated state transfer allows for spectrally filtered detection under resonant excitation. The application of a gate voltage to the QDM device enables continuous transition between direct and indirect excitons, providing control over the overlap of the electron and hole wave function and optimization of graph state generation.
Review
Nanoscience & Nanotechnology
Ying Yu, Shunfa Liu, Chang-Min Lee, Peter Michler, Stephan Reitzenstein, Kartik Srinivasan, Edo Waks, Jin Liu
Summary: This review article presents the physics and technological developments of epitaxial quantum dot devices emitting in the telecom bands for quantum network devices. The challenges and opportunities for future telecom quantum dot devices with improved performance and expanded functionality through hybrid integration are also discussed.
NATURE NANOTECHNOLOGY
(2023)
