Article
Chemistry, Multidisciplinary
Sisi Liu, Chongjian Zhang, Shuangyuan Li, Yong Xia, Kang Wang, Kao Xiong, Haodong Tang, Linyuan Lian, Xinxing Liu, Ming-Yu Li, Manlin Tan, Liang Gao, Guangda Niu, Huan Liu, Haisheng Song, Daoli Zhang, Jianbo Gao, Xinzheng Lan, Kai Wang, Xiao Wei Sun, Ye Yang, Jiang Tang, Jianbing Zhang
Summary: By epitaxially coating a thin PbS shell over the PbSe QDs and in situ halide passivation, a strategy to decouple the restrictive relation between V-OC and J(SC) in QD IR photovoltaics is developed. This approach allows for excellent trap-state control and outstanding performance under filtered solar illumination, providing a new route to overcome the trade-off between V-OC and J(SC) limited by the photoactive layer with a given bandgap.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
Urice N. Tohgha, Alexander M. Watson, Nicholas P. Godman
Summary: The properties of cadmium selenide/zinc sulfide quantum dots can alter the electrowetting behavior of fluorescent nanofluids, with longer alkyl chains showing the most pronounced change in contact angle and stability under applied voltage. Additionally, smaller diameter quantum dots in higher concentrations demonstrate enhanced electrowetting behavior. The fluorescent properties of the QD nanofluids remained unaffected after repeated electrowetting cycles.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Physics, Condensed Matter
Bashdar Rahman Pirot, Nzar Rauf Abdullah, Andrei Manolescu, Vidar Gudmundsson
Summary: We study thermoelectric transport through a serial double quantum dot coupled to two metallic leads with different thermal energies. Coulomb interactions and coherent effects are found to have significant impacts on the transport properties, leading to extra transport channels and enhanced thermoelectric effects.
PHYSICA B-CONDENSED MATTER
(2022)
Article
Physics, Multidisciplinary
P. Scarlino, J. H. Ungerer, D. J. van Woerkom, M. Mancini, P. Stano, C. Mueller, A. J. Landig, J. Koski, C. Reichl, W. Wegscheider, T. Ihn, K. Ensslin, A. Wallraff
Summary: This study investigates the use of semiconductor quantum dots, where electrons or holes are isolated via electrostatic potentials generated by surface gates, in semiconductor quantum technology. By capacitively coupling double-quantum-dot (DQD) charge qubits to high-impedance superconducting quantum interference device array and Josephson-junction array resonators, the researchers were able to tune the interactions between the qubit and the resonator using surface gates. The results show that the qubit-resonator coupling strength, qubit decoherence, and detuning noise affecting the charge qubit are all systematically tunable.
Article
Materials Science, Multidisciplinary
Cheng Shao, Junichiro Shiomi
Summary: Colloidal quantum dots (QDs) superlattices have promising applications in optical, electrical, and optoelectronic devices. The vibrational frequencies of the superlattices can be tuned by changing the QDs' shapes and ligand types, offering potential for phonon engineering. Molecular dynamics simulations reveal that spatially localized modes dominate thermal transport, while inter-QDs coherent modes have limited thermal conductivity. Controlling the ligand morphology is more efficient in engineering the thermal conductivity of QDs superlattices.
MATERIALS TODAY PHYSICS
(2022)
Article
Chemistry, Physical
Tingting Cai, Wenjing Zheng, Qing Chang, Ning Li, Jinlong Yang, Shengliang Hu
Summary: This study presents a novel method of tuning visible light conversion to facilitate the release and activation of H2O2 through the integration of CaO2 with biocompatible carbon dots. The incorporation of carbon dots significantly enhances the catalytic performance of H2O2 released from CaO2.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Multidisciplinary
Margherita Biondi, Min-Jae Choi, Zhibo Wang, Mingyang Wei, Seungjin Lee, Hitarth Choubisa, Laxmi Kishore Sagar, Bin Sun, Se-Woong Baek, Bin Chen, Petar Todorovic, Amin Morteza Najarian, Armin Sedighian Rasouli, Dae-Hyun Nam, Maral Vafaie, Yuguang C. Li, Koen Bertens, Sjoerd Hoogland, Oleksandr Voznyy, F. Pelayo Garcia de Arquer, Edward H. Sargent
Summary: This study introduces a new method to improve facet alignment in CQD solids by adjusting the surface of CQDs, leading to enhanced coupling and improved performance of optoelectronic devices. This approach results in a 10x increase in hole mobility compared to control CQD solids, and enables photodiodes with 70% external quantum efficiency and rapid response times.
ADVANCED MATERIALS
(2021)
Article
Physics, Applied
Martin Nurizzo, Baptiste Jadot, Pierre-Andre Mortemousque, Vivien Thiney, Emmanuel Chanrion, Matthieu Dartiailh, Arne Ludwig, Andreas D. Wieck, Christopher Bauerle, Matias Urdampilleta, Tristan Meunier
Summary: Recent demonstrations using electron spins stored in quantum dot array as qubits show promise for developing a scalable quantum computing platform. By partitioning the system with inter-dot tunnel barriers, the precise control of the quantum dot parameters can be simplified and protection against unwanted charge displacement can be achieved.
APPLIED PHYSICS LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Carlo Nazareno Dibenedetto, Elisabetta Fanizza, Liberato De Caro, Rosaria Brescia, Annamaria Panniello, Raffaele Tommasi, Chiara Ingrosso, Cinzia Giannini, Angela Agostiano, Maria Lucia Curri, Marinella Striccoli
Summary: The study investigates the interaction mechanisms between QDs by forming small heteroassemblies composed of several different-sized CdSe QDs in solution, tuning the interparticle distance by varying the length of the alkyl chain. The research provides a thorough spectroscopic investigation to rationalize the coupling mechanism between the interacting nanoparticles, ranging from charge transfer/wavefunction delocalization to energy transfer, based on their separation distance.
MATERIALS RESEARCH BULLETIN
(2022)
Article
Physics, Multidisciplinary
Li-Wen Tang, Wei-Guo Mao
Summary: By adjusting the coupling strength between the double quantum dots and Majorana bound states (MBS) and the arrangement of magnetic moments of the leads, the magnitude of current can be effectively enhanced or suppressed. Under certain conditions, a negative TMR may emerge for MBS detection. Additionally, the amplitude of TMR can be tuned by varying several system parameters.
FRONTIERS IN PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Hao Zhang, Parinaz Moazzezi, Juanjuan Ren, Brett Henderson, Cristina Cordoba, Vishal Yeddu, Arthur M. Blackburn, Makhsud Saidaminov, Irina Paci, Stephen Hughes, Reuven Gordon
Summary: Perovskite quantum dots (PQDs) show promise in various applications, including efficient solar cells, bright light emitting devices, and quantum sources of light. Researchers used double-nanohole optical trapping to size individual dots and observed the coupling between dots. The findings provide insights for in situ control of PQD growth and studies of their coupling with quantum information applications in mind.
Article
Optics
Zhousu Xu, Wenju Feng, Tao Chen, Xiaofeng Liu, Jianrong Qiu
Summary: Borosilicate glasses doped with PbSe quantum dots were prepared by traditional melt-quenching and thermal treatment. The addition of NaF network modifier enhanced the mobility of Pb2+ and Se2-ions, promoting the precipitation of PbSe QDs. The spectral properties showed a red shift with increased temperature or NaF concentration, accompanied by changes in PL intensity and lifetime. Furthermore, the PL intensity of QD-doped glass fibers was significantly enhanced with the addition of NaF.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Marissa S. Martinez, Michelle A. Nolen, Nicholas F. Pompetti, Lee J. Richter, Carrie A. Farberow, Justin C. Johnson, Matthew C. Beard
Summary: Controlling the binding of functional organic molecules on quantum dot surfaces is crucial for understanding the resulting organic-inorganic hybrid behavior. In this study, the binding of tetracenedicarboxylate ligands on PbS quantum dots was varied through solid-state ligand exchange. Different ligand concentrations led to different structures and properties, with low concentrations resulting in mixed ligand structures, intermediate concentrations resulting in ligand-ligand interactions through hydrogen bonding, and high concentrations resulting in complete ligand exchange.
Article
Green & Sustainable Science & Technology
Yaling Liu, John Keil, Vivian E. Ferry, Uwe R. Kortshagen
Summary: Greenhouses provide a controlled environment for plant growth and offer resilience to droughts and extreme weather. Luminescent solar concentrators (LSCs) have the potential to reduce greenhouse energy demand by generating clean electricity and transmitting enough light for plant growth.
ADVANCED SUSTAINABLE SYSTEMS
(2023)
Article
Physics, Applied
Joshua Ziegler, Florian Luthi, Mick Ramsey, Felix Borjans, Guoji Zheng, Justyna P. Zwolak
Summary: Gate-defined quantum dots have imperfections, such as capacitive crosstalk between metallic gates, which can be compensated by using virtual gates. We demonstrated a reliable automated capacitive coupling identification method that combines machine learning with traditional fitting. We also showed how cross-capacitance measurement can be used to identify spurious quantum dots, providing crucial information for reliable tuning for qubit operations.
PHYSICAL REVIEW APPLIED
(2023)
Article
Multidisciplinary Sciences
Cornelis J. van Diepen, Tzu-Kan Hsiao, Uditendu Mukhopadhyay, Christian Reichl, Werner Wegscheider, Lieven M. K. Vandersypen
Summary: The study demonstrates electron cascade phenomenon induced by Coulomb repulsion in a quantum dot array, transmitting information like toppling dominoes far beyond the direct Coulomb repulsion range. The combination of cascade effect with Pauli spin blockade technology can potentially lead to high-fidelity results in reading distant spins in quantum dot arrays.
NATURE COMMUNICATIONS
(2021)
Article
Physics, Applied
Y. -Y. Liu, S. G. J. Philips, L. A. Orona, N. Samkharadze, T. McJunkin, E. R. MacQuarrie, M. A. Eriksson, L. M. K. Vandersypen, A. Yacoby
Summary: This study focuses on implementing rf readout in accumulation-mode gate-defined quantum dots and testing two methods for mitigating the effect of parasitic capacitance: on-chip modifications and off-chip changes. The research demonstrates that on-chip modifications enable high-performance charge readout in Si/SixGe1-x quantum dots with a fidelity of 99.9% for a measurement time of 1 µs.
PHYSICAL REVIEW APPLIED
(2021)
Article
Multidisciplinary Sciences
Xiao Xue, Maximilian Russ, Nodar Samkharadze, Brennan Undseth, Amir Sammak, Giordano Scappucci, Lieven M. K. Vandersypen
Summary: In this study, a spin-based quantum processor in silicon with high gate fidelities for single-qubit and two-qubit gates was reported. The gate fidelities were above 99.5%, and the processor was used to calculate molecular ground-state energies with high accuracy. The breakthrough in achieving a two-qubit gate fidelity above 99% positions semiconductor qubits for fault tolerance and potential applications in the era of noisy intermediate-scale quantum devices.
Article
Physics, Multidisciplinary
Patrick Harvey-Collard, Jurgen Dijkema, Guoji Zheng, Amir Sammak, Giordano Scappucci, Lieven M. K. Vandersypen
Summary: This study reports the coherent coupling of two electron spins using virtual microwave photons in a silicon double quantum dot. It demonstrates the achievement of the strong dispersive regime of circuit quantum electrodynamics in spin-spin coupling, which is essential for long-range two-qubit gates and scalable networks of spin qubits on a chip.
Article
Multidisciplinary Sciences
Alexey Tiranov, Vasiliki Angelopoulou, Bjorn Schrinski, Cornelis Jacobus van Diepen, Oliver August Dall Alba Sandberg, Ying Wang, Leonardo Midolo, Sven Scholz, Andreas Dirk Wieck, Arne Ludwig, Anders Sondberg Sorensen, Peter Lodahl
Summary: Photon emission is fundamental for light-matter interaction and photonic quantum science. This study demonstrates distant dipole-dipole radiative coupling in solid-state optical quantum emitters embedded in a nanophotonic waveguide. The collective response and emission dynamics can be controlled by proper excitation techniques. This work is a foundational step towards multiemitter applications for scalable quantum-information processing.
Article
Computer Science, Theory & Methods
Eric D. Schoen, Pieter T. Eendebak, Alan R. Vazquez, Peter Goos
Summary: This study proposes a methodology for systematically enumerating conference designs and DSDs, and demonstrates its potential by enumerating all conference designs with up to 24 rows and columns. It also provides DSDs that minimize the correlation among contrast vectors of second-order effects.
STATISTICS AND COMPUTING
(2022)
Article
Physics, Multidisciplinary
Tobias Bonsen, Patrick Harvey -Collard, Maximilian Russ, Jurgen Dijkema, Amir Sammak, Giordano Scappucci, Lieven M. K. Vandersypen
Summary: We report on observations of transitions between excited states in the Jaynes-Cummings ladder of circuit quantum electrodynamics with electron spins (spin circuit QED). Unexplained features in recent experimental work are found to correspond to these transitions, and an input-output framework that incorporates these effects is presented. New experiments reproduce previous observations and demonstrate excited-state transitions and multiphoton transitions by increasing the probe power and using two-tone spectroscopy. The ability to probe the Jaynes-Cummings ladder is facilitated by improvements in the coupling-to-decoherence ratio, highlighting the increased maturity of spin circuit QED as an intriguing platform for studying quantum phenomena.
PHYSICAL REVIEW LETTERS
(2023)
Article
Multidisciplinary Sciences
Brian Paquelet Wuetz, Davide Degli Esposti, Anne-Marije J. Zwerver, Sergey V. Amitonov, Marc Botifoll, Jordi Arbiol, Lieven M. K. Vandersypen, Maximilian Russ, Giordano Scappucci
Summary: Improving the material stack of gate-defined quantum dots in Si-28/SiGe heterostructure is crucial for reducing charge noise in the host semiconductor. By studying the semiconductor-dielectric interface and the buried quantum well, it is found that enhancements in scattering properties and uniformity of the two-dimensional electron gas result in a significant reduction in charge noise. Extrapolating the measured charge noise to simulated dephasing times shows a potential improvement in CZ-gate fidelities by nearly one order of magnitude.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Applied
Brennan Undseth, Xiao Xue, Mohammad Mehmandoost, Maximilian Rimbach-Russ, Pieter T. Eendebak, Nodar Samkharadze, Amir Sammak, Viatcheslav V. Dobrovitski, Giordano Scappucci, Lieven M. K. Vandersypen
Summary: Micromagnet-based electric dipole spin resonance is a promising method for scaling silicon spin qubits in gate-defined quantum dots, while maintaining long coherence times and high control fidelities. However, understanding and mitigating cross-talk mechanisms is crucial for accurately controlling dense arrays of qubits using a multiplexed drive. We identified an unexpected cross-talk mechanism where the Rabi frequency of a driven qubit is significantly affected by the drive of an adjacent qubit. These findings have important implications for scaling single-qubit control.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Applied
F. K. Unseld, M. Meyer, M. T. Madzik, F. Borsoi, S. L. de Snoo, S. V. Amitonov, A. Sammak, G. Scappucci, M. Veldhorst, L. M. K. Vandersypen
Summary: Semiconductor spin qubits have attracted attention as a potential platform for fault-tolerant quantum computing. In this study, researchers successfully created a tunnel-coupled 2x2 quantum dot array in a Si-28/SiGe heterostructure using high-quality materials and carefully designed gate patterns. By loading a single electron into each of the four quantum dots, the researchers were able to achieve the specific charge state (1,1,1,1). This work provides valuable information for the design of 2D quantum dot arrays and represents a significant step towards the operation of spin qubits in Si-28/SiGe quantum dots in two dimensions.
APPLIED PHYSICS LETTERS
(2023)
Article
Quantum Science & Technology
A. M. J. Zwerver, S. Amitonov, S. L. de Snoo, M. T. Madzik, M. Rimbach-Russ, A. Sammak, G. Scappucci, L. M. K. Vandersypen
Summary: Coherent links between distant spin qubits can be achieved by shuttling the electron spin through an array of quantum dots. In this experiment, we move an electron spin through a linear array of four tunnel-coupled quantum dots by adjusting the electrochemical potential for each dot. The estimated spin-flip probability per hop is below 0.01% based on the experimental results.
Article
Materials Science, Multidisciplinary
Luca Petit, Maximilian Russ, Gertjan H. G. J. Eenink, William I. L. Lawrie, James S. Clarke, Lieven M. K. Vandersypen, Menno Veldhorst
Summary: In this study, the implementation of SWAP, CPHASE, and CNOT-class two-qubit gates in a silicon device, even at temperatures above 1 K, is successfully demonstrated, which is of great importance for scalable quantum information.
COMMUNICATIONS MATERIALS
(2022)
Article
Physics, Multidisciplinary
J. Knoerzer, C. J. van Diepen, T-K Hsiao, G. Giedke, U. Mukhopadhyay, C. Reichl, W. Wegscheider, J. Cirac, L. M. K. Vandersypen
Summary: This article presents a detailed experimental characterization of long-range electron-electron interactions in an array of gate-defined semiconductor quantum dots. Significant interaction strength among electrons separated by up to four sites is demonstrated, and the experimental results match well with the theoretical predictions of screening effects. Numerical simulations show that about ten quantum dots are sufficient for observing binding in a one-dimensional H-2-like molecule. These findings pave the way for future quantum simulations and benchmarks of numerical methods in quantum chemistry.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Mario Lodari, Nico W. Hendrickx, William I. L. Lawrie, Tzu-Kan Hsiao, Lieven M. K. Vandersypen, Amir Sammak, Menno Veldhorst, Giordano Scappucci
Summary: This research focuses on engineered planar Ge/SiGe heterostructures with low disorder potential landscape, suitable for quiet operation of hole quantum dots. The study demonstrates promising results for scaled two-dimensional spin qubit arrays using planar Ge technology.
MATERIALS FOR QUANTUM TECHNOLOGY
(2021)
