Article
Multidisciplinary Sciences
Nadia O. Antoniadis, Mark R. Hogg, Willy F. Stehl, Alisa Javadi, Natasha Tomm, Ruediger Schott, Sascha R. Valentin, Andreas D. Wieck, Arne Ludwig, Richard J. Warburton
Summary: To improve the rapid and high-fidelity single-shot readout of quantum states, researchers used an open microcavity to enhance the optical readout signal from a semiconductor quantum dot spin state. They achieved a record readout time of only 3 nanoseconds with a fidelity of (95.2 ± 0.7)%, and observed quantum jumps using repeated single-shot measurements. This work opens up new possibilities for the use of semiconductor quantum dots in quantum technologies.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Applied
Lena Engel, Sascha Kolatschek, Thomas Herzog, Sergej Vollmer, Michael Jetter, Simone L. Portalupi, Peter Michler
Summary: In this study, the coupling of a truncated Gaussian-shaped microcavity to a quantum dot (QD) was achieved using wet-chemical etching and epitaxial semiconductor overgrowth. Experimental results confirmed the agreement with simulations in terms of cavity modes and their spatial profiles. By tuning the temperature, transitions of a QD inside the cavity between resonance and off resonance were successfully achieved. The Purcell enhancement effect and the single-photon characteristic of the QD were preserved, as evidenced by a reduced decay time and second-order correlation measurements.
APPLIED PHYSICS LETTERS
(2023)
Article
Optics
Si Zhu, Xiang Ma, Can Liu, Wei Luo, Jia Liu, Bei Shi, Weihua Guo, Kei May Lau
Summary: This paper introduces an efficient and easy fabrication method for whispering-gallery-mode (WGM) manipulation and reports the first electrically driven single-mode quantum dot micro-ring (QDMR) lasers. By utilizing self-assembled InAs/InAlGaAs QD active layers with deeply etched azimuthal gratings, continuous-wave (CW) lasing with controllable single-mode emission wavelengths within the range of 1300 nm to 1370 nm has been achieved, with a record-high side-mode-suppression-ratio (SMSR) value of 49 dB. These QDMR lasers exhibit excellent single-mode lasing stabilities over the current and temperature tuning range, with a thermal tunability of 0.092 nm/degrees C, and the concept is applicable to other wavelength bands.
Article
Chemistry, Multidisciplinary
Quanbo Jiang, Prithu Roy, Jean-Benoit Claude, Jerome Wenger
Summary: In this research, plasmonic nanoantennas were used to trap single colloidal quantum dots and enhance their photoluminescence without the need for further processing, achieving precise positioning of the quantum emitter at the nanoantenna hotspot. The dedicated nanoantenna design exhibited high trap stiffness for quantum dot trapping and relatively low trapping power, resulting in significantly improved emission characteristics of the single quantum dot.
Article
Quantum Science & Technology
Michael Cosacchi, Tim Seidelmann, Adam Mielnik-Pyszczorski, Miriam Neumann, Thomas K. Bracht, Moritz Cygorek, Alexei Vagov, Doris E. Reiter, Vollrath M. Axt
Summary: This paper proposes a single-photon buffering device composed of a quantum dot doped with a single Mn atom, and achieves the storage and retrieval of photons through optical methods.
ADVANCED QUANTUM TECHNOLOGIES
(2022)
Article
Multidisciplinary Sciences
B. Jonas, D. Heinze, E. Schoell, P. Kallert, T. Langer, S. Krehs, A. Widhalm, K. D. Joens, D. Reuter, S. Schumacher, A. Zrenner
Summary: The authors introduce an all-optical nonlinear method to tailor and control the single photon emission. They demonstrate energy tuning and polarization control of the emitted photons through a laser-controlled down-conversion process.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
Friedrich Sbresny, Lukas Hanschke, Eva Schoell, William Rauhaus, Bianca Scaparra, Katarina Boos, Eduardo Zubizarreta Casalengua, Hubert Riedl, Elena del Valle, Jonathan J. Finley, Klaus D. Joens, Kai Mueller
Summary: A scheme for generating highly indistinguishable single photons using semiconductor quantum dots is proposed and demonstrated. The scheme utilizes the resonant two-photon excitation of the biexciton and precise timing of the stimulation pulse to achieve high indistinguishability and low multiphoton errors. Additionally, the polarization of the stimulation pulse allows for deterministic programming of the emitted photon's polarization, resulting in higher brightness compared to cross-polarized resonant excitation.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Yuqing Huang, Rui Su, Yubin Wang, Chao Zhu, Jiangang Feng, Jiaxin Zhao, Zheng Liu, Qihua Xiong
Summary: The cavity-photon interface effectively suppresses the temperature-activated spectral diffusion of perovskite nanocrystals, achieving highly stable single-photon emission. This study sheds light on the nature of spectral diffusion in perovskite nanocrystals and provides a method to control single-photon emission.
Article
Quantum Science & Technology
Pascal Kobel, Moritz Breyer, Michael Koehl
Summary: This research has achieved deterministic quantum entanglement with high fidelity between a trapped ion and a photon emitted into the resonator mode. The success probability for generation and detection of entanglement for a single shot is 2.5 x 10(-3), resulting in an entanglement rate of 62 Hz.
NPJ QUANTUM INFORMATION
(2021)
Article
Chemistry, Multidisciplinary
Jonathan Jurkat, Sebastian Klembt, Marco De Gregorio, Moritz Meinecke, Quirin Buchinger, Tristan H. Harder, Johannes Beierlein, Oleg A. Egorov, Monika Emmerling, Constantin Krause, Christian Schneider, Tobias Huber-Loyola, Sven Hoefling
Summary: The introduction of topological physics to photonics has resulted in the development of robust photonic devices. While classical topological protection of light has been achieved, the utilization of quantum light sources in devices with topologically nontrivial resonances remains largely unexplored.
Article
Optics
Niels Heermeier, Tobias Heuser, Jan Grosse, Natalie Jung, Arsenty Kaganskiy, Markus Lindemann, Nils C. Gerhardt, Martin R. Hofmann, Stephan Reitzenstein
Summary: Spin-controlled lasers and high-beta quantum dot micropillar lasers are two fascinating photonic devices with potential applications. The experimental and predicted polarization oscillation frequencies of spin-laser effects are presented, demonstrating the possibility of developing more compact, faster, and more energy-efficient spin-lasers.
LASER & PHOTONICS REVIEWS
(2022)
Article
Physics, Multidisciplinary
A. Beregi, A. Pontin, P. F. Barker
Summary: The study investigates the role of stimulated Brillouin scattering in a fiber cavity and an optomechanical system based on nonlinear Brillouin scattering. It shows optimal damping for low mechanical resonance frequencies in the hybrid optomechanical system, with blue detuning providing the best damping results compared to standard optomechanics. The study also explores the potential of cooling a mechanical oscillator to the quantum ground state.
NEW JOURNAL OF PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Nima Taghipour, Mariona Dalmases, Guy Luke Whitworth, Yongjie Wang, Gerasimos Konstantatos
Summary: Achieving low-threshold infrared stimulated emission in solution-processed quantum dots is critical for real-life applications. This Letter demonstrates the potential of ultra-low-threshold infrared stimulated emission using cascade charge transfer (CT) in Pb-chalcogenide colloidal quantum dot (CQD) solids.
Article
Multidisciplinary Sciences
L. Banszerus, K. Hecker, S. Moeller, E. Icking, K. Watanabe, T. Taniguchi, C. Volk, C. Stampfer
Summary: The authors report on the measurement of spin relaxation time exceeding 200 μs for single-electron in bilayer graphene quantum dots. The results indicate a strong dependence on spin splitting, promising even longer relaxation times at lower magnetic fields. These findings suggest that graphene can serve as a promising host material for scalable spin qubits.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Erik R. Eisenach, John F. Barry, Michael F. O'Keeffe, Jennifer M. Schloss, Matthew H. Steinecker, Dirk R. Englund, Danielle A. Braje
Summary: Overcoming poor readout in solid-state spin defect devices is becoming increasingly urgent, with rapid adoption in quantum sensing, quantum information, and fundamental physics tests. By coupling to a microwave cavity, high-fidelity room-temperature readout of nitrogen-vacancy centers was demonstrated, achieving magnetic sensitivity approaching the Johnson-Nyquist noise limit.
NATURE COMMUNICATIONS
(2021)
Article
Physics, Condensed Matter
G. R. Haripriya, T. W. Heitmann, D. K. Yadav, G. C. Kaphle, Madhav Prasad Ghimire, R. Pradheesh, J. Joshi, P. Vora, K. Sethupathi, V Sankaranarayanan, H. S. Nair
Summary: In this study, the electronic and magnetic properties of Dy(2)FeCoO(6) were investigated using various experimental techniques and theoretical calculations. Two magnetic phase transitions were found, along with details regarding the structure and magnetic moments of the material. The experimental antiferromagnetic structure was supported by DFT calculations predicting an insulating electronic state in Dy2FeCoO6.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Physics, Condensed Matter
P. G. Brereton, D. Puent, J. Vanhoy, E. R. Glaser, S. G. Carter
SOLID STATE COMMUNICATIONS
(2020)
Article
Physics, Multidisciplinary
Samuel G. Carter, Stefan C. Badescu, Allan S. Bracker, Michael K. Yakes, Kha X. Tran, Joel Q. Grim, Daniel Gammon
Summary: By utilizing a trion with one hole in an excited orbital, the strong spin-orbit interaction in quantum dots allows for optical spin rotations and cycling transitions, addressing the compatibility issue for quantum information applications. The specific trion triplet forms a double Lambda system even in a Faraday magnetic field, enabling fast hole spin initialization and coherent population trapping. Furthermore, the lowest trion transitions still effectively preserve spin, allowing for fast optical spin control combined with cycling transitions for spin readout.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Shojan P. Pavunny, Andrew L. Yeats, Hunter B. Banks, Edward Bielejec, Rachael L. Myers-Ward, Matthew T. DeJarld, Allan S. Bracker, D. Kurt Gaskill, Samuel G. Carter
Summary: Point defects in SiC are an ideal platform for quantum information and sensing applications due to their long spin coherence times, optical spin initialization, and spin-dependent fluorescence readout. The precise spatial patterning of arrays of silicon vacancy emitters has been demonstrated in an epitaxial 4H-SiC layer through mask-less focused ion beam implantation, with scalable and reproducible defect generation achieved.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Applied
John B. S. Abraham, Cameron Gutgsell, Dalibor Todorovski, Scott Sperling, Jacob E. Epstein, Brian S. Tien-Street, Timothy M. Sweeney, Jeremiah J. Wathen, Elizabeth A. Pogue, Peter G. Brereton, Tyrel M. McQueen, Wesley Frey, B. D. Clader, Robert Osiander
Summary: Silicon vacancy in silicon carbide is considered an ideal choice for spin-defect-based quantum sensors due to its high spin number and temperature-independent ground-state zero-field splitting. By optimizing anneal parameters and minimizing power broadening, nanotesla shot-noise-limited ensemble magnetometry can be achieved, showcasing a low-cost and simple approach to quantum sensing of magnetic fields.
PHYSICAL REVIEW APPLIED
(2021)
Review
Chemistry, Multidisciplinary
Sugata Chowdhury, Albert F. Rigosi, Heather M. Hill, Patrick Vora, Angela R. Hight Walker, Francesca Tavazza
Summary: This review focuses on computational efforts and advancements in the field of charge density waves (CDWs) in two-dimensional (2D) materials. It covers various subtopics such as computational techniques, resulting atomic structures, electron-phonon interaction effects, confinement and dimensionality effects, and future outlook.
Article
Nanoscience & Nanotechnology
Jaydeep Joshi, Benedikt Scharf, Igor Mazin, Sergiy Krylyuk, Daniel J. Campbell, Johnpierre Paglione, Albert Davydov, Igor Zutic, Patrick M. Vora
Summary: Interfaces in layered heterostructures provide a fertile ground for exploring new physics. This article investigates an unexpected photoluminescence peak at the interface between TiSe2 and MoSe2, which disappears at the charge density wave transition. The results present a challenge for theoretical understanding and offer a fascinating avenue for engineering excitons through interactions with charge density waves.
Article
Physics, Multidisciplinary
Kha X. Tran, Allan S. Bracker, Michael K. Yakes, Joel Q. Grim, Samuel G. Carter
Summary: This study directly measures the coherence time of singlet-triplet states in a pair of coupled dots, uncovering the main dephasing mechanisms to be electrical noise and a magnetic field dependent interaction with nuclear spins.
PHYSICAL REVIEW LETTERS
(2022)
Article
Education, Scientific Disciplines
Ciaran Hughes, Doug Finke, Dan-Adrian German, Celia Merzbacher, Patrick M. Vora, H. J. Lewandowski
Summary: With the emergence of the quantum industry, there is a need to train a new workforce in quantum information science and technology. A survey of 57 companies in the quantum industry reveals a variety of job opportunities, ranging from highly specialized roles to broader job categories. These jobs require a range of skills and various degree levels.
IEEE TRANSACTIONS ON EDUCATION
(2022)
Article
Chemistry, Multidisciplinary
Peter E. Siegfried, Hari Bhandari, Jeanie Qi, Rojila Ghimire, Jayadeep Joshi, Zachary T. Messegee, Willie B. Beeson, Kai Liu, Madhav Prasad Ghimire, Yanliu Dang, Huairuo Zhang, Albert V. Davydov, Xiaoyan Tan, Patrick M. Vora, Igor I. Mazin, Nirmal J. Ghimire
Summary: By utilizing ab initio calculations and measurements of magnetic, thermal, and transport properties, it is demonstrated that orthorhombic CoTe2 is near ferromagnetism, which is suppressed by spin fluctuations. Calculations and transport measurements reveal the presence of nodal Dirac lines, making it a rare combination of proximity to quantum criticality and Dirac topology.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Coatings & Films
Margaret A. Stevens, Wayne McKenzie, Gerald Baumgartner, Joel Q. Grim, Samuel G. Carter, Allan S. Bracker
Summary: We investigate the manipulation of surface diffusion to grow quantum dots without using high-index substrates or metamorphic buffers by molecular beam epitaxy. We compare the surface diffusion characteristics of In on In0.52Al0.48As with In and Ga on In0.53Ga0.47As, and apply a two-step arsenic exposure protocol to modify the droplet crystallization step, resulting in a series of different nanostructure morphologies with narrow-linewidth emission between 1200 and 1520 nm at 4 K. We ultimately demonstrate that controlling surface diffusion of the group-III species during growth is critical for achieving quantum dots appropriate for single-photon sources at telecommunication wavelengths.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2023)
Article
Engineering, Electrical & Electronic
Scott Melis, Samantha Hung, Chaitali Bagade, Yuri Chung, Eleni Hughes, Xinran Zhang, Paola Barbara, Peize Han, Tingting Li, Daniel McCusker, Robert Hartsmith, Jeffery Bertke, Pratibha Dev, Iris Stone, Jaydeep Joshi, Patrick Vora, Edward Van Keuren
Summary: This study presents the optical and electronic characterization of the charge transfer cocrystal phenothiazine-tetracyanoquinodimethane (PTZ-TCNQ). The low energy CT states and changes in the Raman spectra are identified using density functional theory calculations. Long, ribbon-like oriented cocrystals are fabricated using an evaporative alignment method and fabricated into organic field effect transistors.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Kevin Ye, Nathan Z. Koocher, Stephen Filippone, Shanyuan Niu, Boyang Zhao, Matthew Yeung, Sharon Bone, Adam J. Robinson, Patrick Vora, Andre Schleife, Long Ju, Alexey Boubnov, James M. Rondinelli, Jayakanth Ravichandran, R. Jaramillo
Summary: Chalcogenide perovskites and related layered structures have potential applications in optoelectronics and energy conversion technologies. However, experimental studies on these compounds are limited. In this study, experimental and theoretical methods are used to investigate the electronic structure and physical properties of chalcogenide perovskites, highlighting the role of covalent bonding in charge transport.
Article
Quantum Science & Technology
I Lekavicius, R. L. Myers-Ward, D. J. Pennachio, J. R. Hajzus, D. K. Gaskill, A. P. Purdy, A. L. Yeats, P. G. Brereton, E. R. Glaser, T. L. Reinecke, S. G. Carter
Summary: In solid-state spin systems, unwanted interactions with surrounding spin baths and inhomogeneity are common challenges. The silicon vacancy in silicon carbide (SiC) can alleviate many of these issues and improve performance through isotopic purification and choosing the basis state in the spin quartet.
