Article
Physics, Applied
Takeru Utsugi, Noriyuki Lee, Ryuta Tsuchiya, Toshiyuki Mine, Raisei Mizokuchi, Jun Yoneda, Tetsuo Kodera, Shinichi Saito, Digh Hisamoto, Hiroyuki Mizuno
Summary: Loading single electrons into an array of quantum dots is essential for developing scalable silicon-based quantum computers, but the variability of quantum dot characteristics presents significant challenges. In this study, we used a single-electron pump to load single electrons into a quantum dot array, achieving 100 MHz operation with 99% accuracy at 4 K. By controlling the timing of subsequent gates, we minimized jitter in electron transfer to less than 10 ns, suitable for typical silicon qubit operating speeds around 1 MHz.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
V. P. Michal, J. C. Abadillo-Uriel, S. Zihlmann, R. Maurand, Y. -M. Niquet, M. Filippone
Summary: We study a spin circuit-QED device, where a superconducting microwave resonator is connected to a single hole confined in a semiconductor quantum dot via capacitance. The gyromagnetic g matrix of the hole can be electrically modulated due to the strong spin-orbit coupling inherent in valence-band states. This modulation allows for coupling between the photons in the resonator and the hole spin. We demonstrate that the spin-photon interaction can be controlled through gate voltages and magnetic field orientation, and the character of the interaction can switch from fully transverse to fully longitudinal.
Article
Materials Science, Multidisciplinary
A. Aarab, R. Azouit, V Reiher, Y. Berube-Lauziere
Summary: A measurement-based quantum feedback protocol is developed for spin-state initialization in a gate-defined double quantum dot spin qubit coupled to a superconducting cavity. The protocol improves qubit state initialization by enabling robust preparation of the spin in shorter time and achieving higher fidelity. Additionally, it is effective at high temperatures.
Article
Chemistry, Multidisciplinary
Youngmin Lee, Hyewon Jun, Seoyeon Park, Deuk Young Kim, Sejoon Lee
Summary: The transport characteristics of a gate-all-around Si multiple-quantum-dot (QD) transistor were studied experimentally and parametrized using theoretical models. The device was fabricated using e-beam lithography to create ultrasmall QDs along a Si nanowire channel. The device exhibited Coulomb blockade oscillation (CBO) and negative differential conductance (NDC) at room temperature, which could evolve in wide bias voltage ranges. Analysis confirmed that the QD transistor was a double-dot system and the formation of imbalanced ultrasmall QDs led to effective CBO/NDC evolution in wide voltage ranges.
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
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
Multidisciplinary Sciences
Ke Wang, Gang Xu, Fei Gao, He Liu, Rong-Long Ma, Xin Zhang, Zhanning Wang, Gang Cao, Ting Wang, Jian-Jun Zhang, Dimitrie Culcer, Xuedong Hu, Hong-Wen Jiang, Hai-Ou Li, Guang-Can Guo, Guo-Ping Guo
Summary: Hole-spin qubits in germanium show promise for rapid, all-electrical qubit control. The authors demonstrate ultrafast single-spin manipulation in a hole-based double quantum dot in a germanium hut wire, with a record Rabi frequency exceeding 540 MHz. These results suggest the potential for ultrafast coherent control of hole spin qubits to meet the requirements for scalable quantum information processing.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Youngmin Lee, So Hyun Lee, Hyo Seok Son, Sejoon Lee
Summary: This study designed high-performance Si single-electron transistors that operate at room-temperature using a multiple quantum-dot multiple tunnel junction system. The research demonstrates that the modulation of subbands in the volumetrically undulated Si nanowires enables energy stability and high performance at room temperature.
Review
Chemistry, Analytical
Yanan Zhang, Ning Cai, Vincent Chan
Summary: With the development of nanotechnology, fluorescent silicon nanomaterials have been synthesized and applied in various areas. Among them, silicon quantum dots (SiQDs) are a new class of zero-dimensional nanomaterials with outstanding optical properties, benign biocompatibility, and ultra-small size. In recent years, SiQDs have been gradually utilized for constructing high-performance fluorescent sensors for chemical or biological analytes. Herein, we focus on reviewing recent advances in SiQD-based fluorescent biosensors from a broad perspective and discussing possible future trends.
Article
Optics
Yifan Zhu, Wenqi Wei, Ailun Yi, Tingting Jin, Chen Shen, Xudong Wang, Liping Zhou, Chengli Wang, Weiwen Ou, Sannian Song, Ting Wang, Jianjun Zhang, Xin Ou, Jiaxiang Zhang
Summary: Hybrid integration of wafer-scale 4H-SiC photonic chips with InGaAs quantum dot-based single-photon sources using ion slicing technique enables efficient routing of single-photon emission and integrated photon splitting operation.
LASER & PHOTONICS REVIEWS
(2022)
Article
Chemistry, Multidisciplinary
Yang Zhang, Yuning Li, Qing You, Jingye Sun, Ke Li, Hao Hong, Lingbing Kong, Mingqiang Zhu, Tao Deng, Zewen Liu
Summary: In this paper, a 3D photodetector based on a graphene-SWCNT heterojunction is fabricated using a self-rolled-up process. The 3D microcavity structure enhances the optical field and improves the photoresponsivity compared to 2D devices. The photodetector demonstrates broadband photodetection, fast photoresponse speed, excellent sensitivity, mid-infrared detection, and room-temperature imaging capability. This 3D heterojunction photodetector provides a feasible pathway for high-performance graphene-based photodetectors and can be integrated with other light absorptive materials.
Article
Multidisciplinary Sciences
Waqar Khan, Patrick P. Potts, Sebastian Lehmann, Claes Thelander, Kimberly A. Dick, Peter Samuelsson, Ville F. Maisi
Summary: Efficient conversion of microwave photons into electrical current, with a 6% efficiency, has been demonstrated in double quantum dots, showing potential for applications in quantum technologies.
NATURE COMMUNICATIONS
(2021)
Article
Quantum Science & Technology
Nathan Holman, D. Rosenberg, D. Yost, J. L. Yoder, R. Das, William D. Oliver, R. McDermott, M. A. Eriksson
Summary: The study presents a method to address the dense wiring requirements for scaling quantum dot qubits by using superconducting resonators and 3D integration. Successful integration of an off-chip high-impedance TiN resonator with a double quantum dot demonstrates the feasibility of this approach.
NPJ QUANTUM INFORMATION
(2021)
Article
Nanoscience & Nanotechnology
Chia-Ching Huang, Yingying Tang, Marco van der Laan, Jorik van de Groep, A. Femius Koenderink, Katerina Dohnalova
Summary: The study directly assessed the size dependence of the optical band gap and found that the optical band gap is given by the amorphous shell. It proposes that structural disorder might be the reason behind the limited emission tunability from various Si-NPs. The results suggest a pressing need for development and broader use of direct correlative single-dot microscopy methods.
ACS APPLIED NANO MATERIALS
(2021)
Article
Biochemistry & Molecular Biology
Vahideh Khademhosseini, Daryoosh Dideban, Mohammad Taghi Ahmadi, Hadi Heidari
Summary: The single electron transistor (SET) is a nanoscale switching device that operates based on the tunneling of single electrons. In this study, multiple quantum dot islands such as graphene nanoscroll-carbon nanotubes (GNS-CNT) and graphene nanoscroll-fullerene (GNS-C-60) are used in SET devices. The impacts of important parameters such as temperature and applied gate voltage on the current of these SETs are investigated, along with the effects of various structural factors on the current. The results show that the GNS-CNT SET has a lower Coulomb blockade range and a higher current than the GNS-C-60 SET.
Article
Physics, Applied
T. J. Evans, W. Huang, J. Yoneda, R. Harper, T. Tanttu, K. W. Chan, F. E. Hudson, K. M. Itoh, A. Saraiva, C. H. Yang, A. S. Dzurak, S. D. Bartlett
Summary: Benchmarking and characterizing quantum states and logic gates are crucial in the development of quantum computing devices. This paper introduces a Bayesian approach called fast Bayesian tomography (FBT) for self-consistent process tomography and demonstrates its performance in characterizing a two-qubit gate set on a silicon-based spin qubit device.
PHYSICAL REVIEW APPLIED
(2022)
Article
Physics, Applied
I Hansen, A. E. Seedhouse, K. W. Chan, F. E. Hudson, K. M. Itoh, A. Laucht, A. Saraiva, C. H. Yang, A. S. Dzurak
Summary: This study demonstrates a proof-of-principle for the SMART qubit protocol, showing increased robustness and improved coherence time and gate fidelity for quantum bits. The scalability and relaxation of engineering constraints provided by this protocol offer new possibilities for large-scale quantum processors.
APPLIED PHYSICS REVIEWS
(2022)
Article
Computer Science, Hardware & Architecture
Wen Xun Lian, Harikrishnan Ramiah, Gabriel Chong, Kishore Kumar Pakkirisami Churchill, Nai Shyan Lai, Yong Chen, Pui-In Mak, Rui P. Martins
Summary: This article presents a fully integrated CMOS radio frequency energy-harvesting front end with a stacked step-up transformer and a cross-coupled differential drive rectifier to enhance input sensitivity. The front end achieved improved sensitivity at 900 MHz under different load conditions.
IEEE TRANSACTIONS ON VERY LARGE SCALE INTEGRATION (VLSI) SYSTEMS
(2022)
Article
Nanoscience & Nanotechnology
Will Gilbert, Tuomo Tanttu, Wee Han Lim, MengKe Feng, Jonathan Y. Huang, Jesus D. Cifuentes, Santiago Serrano, Philip Y. Mai, Ross C. C. Leon, Christopher C. Escott, Kohei M. Itoh, Nikolay V. Abrosimov, Hans-Joachim Pohl, Michael L. W. Thewalt, Fay E. Hudson, Andrea Morello, Arne Laucht, Chih Hwan Yang, Andre Saraiva, Andrew S. Dzurak
Summary: This study demonstrates fast electrical control of electron spin in silicon quantum dots by exploiting the switchable interaction between spin and orbital motion of electrons without using a micromagnet. By controlling the energy quantization of electrons in nanostructures, the weak effects of the relativistic spin-orbit interaction in silicon are enhanced, leading to a significant increase in Rabi frequency. The achieved coherence time, gate performance, and gate fidelity show the potential for high-performance all-electrical control in scalable silicon quantum computing.
NATURE NANOTECHNOLOGY
(2023)
Review
Computer Science, Information Systems
Yi Chen Lee, Harikrishnan Ramiah, Alexander Choo, Kishore Kumar Pakkirisami Churchill, Nai Shyan Lai, Chee Cheow Lim, Yong Chen, Pui-In Mak, Rui P. Martins
Summary: This paper reviews and explores the alternative approach of a multiband RF energy-harvesting front-end system, which covers all essential circuitry. It aims to fill the research gap in the further advancement of multiband RF energy harvesting towards enhancing its performance through optimal circuit integration of the front-end system.
Article
Chemistry, Multidisciplinary
Zeheng Wang, MengKe Feng, Santiago Serrano, William Gilbert, Ross C. C. Leon, Tuomo Tanttu, Philip Mai, Dylan Liang, Jonathan Y. Huang, Yue Su, Wee Han Lim, Fay E. Hudson, Christopher C. Escott, Andrea Morello, Chih Hwan Yang, Andrew S. Dzurak, Andre Saraiva, Arne Laucht
Summary: This study investigates the potential of elongated quantum dots, known as jellybean quantum dots, as qubit-qubit couplers. Through experimental measurements and simulations, it is found that under low electron occupancies, the jellybean quantum dots form a tunable, artificial molecule composed of three coupled dots. Under high electron occupancies, they merge into one large dot with well-defined spin states, demonstrating the potential of jellybean dots as qubit couplers in future quantum computing architectures.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Ik Kyeong Jin, Krittika Kumar, Matthew J. Rendell, Jonathan Yue Huang, Chris C. Escott, Fay E. Hudson, Wee Han Lim, Andrew S. Dzurak, Alexander R. Hamilton, Scott D. Liles
Summary: Holes in silicon quantum dots are explored for their potential as high-speed, customizable, and scalable qubits in semiconductor quantum circuits. Challenges include difficulties in charge sensing and controlling coupling between adjacent dots. A solution is presented with the fabrication of an ambipolar complementary metal-oxide-semiconductor (CMOS) device using multilayer palladium gates. The device includes an electron charge sensor and a hole double quantum dot, enabling control of spin state and smooth interdot coupling control. The results demonstrate improvements in hole spin-qubits' quality and controllability.
Article
Instruments & Instrumentation
J. -P. Girard, R. E. Lake, W. Liu, R. Kokkoniemi, E. Visakorpi, J. Govenius, M. Mottonen
Summary: Recently, progress has been made in ultrasensitive microwave detectors, but their range of applications is limited due to a lack of compatibility with broad-band metrologically traceable power absorption measurements. In this study, an ultralow-noise nanobolometer with an additional dc heater input was used to make such measurements. The power absorption was traced by comparing the bolometer response between radio frequency and dc-heating powers traced to the Josephson voltage and quantum Hall resistance. The ability to accurately measure the attenuation of a coaxial input line between 50 MHz and 7 GHz with an uncertainty down to 0.1 dB at a typical input power of -114 dBm was demonstrated.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Review
Quantum Science & Technology
Mateo Casariego, Emmanuel Zambrini Cruzeiro, Stefano Gherardini, Tasio Gonzalez-Raya, Rui Andre, Goncalo Frazao, Giacomo Catto, Mikko Moettoenen, Debopam Datta, Klaara Viisanen, Joonas Govenius, Mika Prunnila, Kimmo Tuominen, Maximilian Reichert, Michael Renger, Kirill G. Fedorov, Frank Deppe, Harriet van der Vliet, A. J. Matthews, Yolanda Fernandez, R. Assouly, R. Dassonneville, B. Huard, Mikel Sanz, Yasser Omar
Summary: The field of propagating quantum microwaves is gaining attention for its promising technological applications in communication and sensing. Despite similarities with quantum optics, the development of a controllable quantum microwave interface is still in its early stages. This article argues for the need of a fully operative toolbox for propagating quantum microwaves, and explores novel directions of research such as microwave quantum key distribution, quantum radar, bath-system learning, and direct dark matter detection. It serves as both a review of the state-of-the-art and an illustration of the wide range of applications that quantum microwaves can offer in the future.
QUANTUM SCIENCE AND TECHNOLOGY
(2023)
Article
Quantum Science & Technology
Fabian Marxer, Antti Vepsalainen, Shan W. Jolin, Jani Tuorila, Alessandro Landra, Caspar Ockeloen-Korppi, Wei Liu, Olli Ahonen, Adrian Auer, Lucien Belzane, Ville Bergholm, Chun Fai Chan, Kok Wai Chan, Tuukka Hiltunen, Juho Hotari, Eric Hyyppae, Joni Ikonen, David Janzso, Miikka Koistinen, Janne Kotilahti, Tianyi Li, Jyrgen Luus, Miha Papic, Matti Partanen, Jukka Raebinae, Jari Rosti, Mykhailo Savytskyi, Marko Seppala, Vasilii Sevriuk, Eelis Takala, Brian Tarasinski, Manish J. Thapa, Francesca Tosto, Natalia Vorobeva, Liuqi Yu, Kuan Yen Tan, Juha Hassel, Mikko Mottonen, Johannes Heinsoo
Summary: This study demonstrates a tunable qubit-qubit coupler based on a floating transmon device, allowing for at least 2 mm separation between qubits while maintaining over 50-MHz coupling. The couplings are mediated by waveguides instead of direct capacitive couplings, reducing the impact of the qubit-qubit distance. The large qubit-qubit distance lowers unwanted non-nearest-neighbor coupling and allows multiple control lines to cross over the structure with minimal crosstalk. A controlled -Z gate with (99.81 +/- 0.02)% fidelity is achieved using this flexible and scalable architecture.
Article
Optics
Ingvild Hansen, Amanda E. Seedhouse, Andre Saraiva, Andrew S. Dzurak, Chih Hwan Yang
Summary: The filter function formalism in quantum control theory is commonly used to assess the noise susceptibility of pulse sequences. However, this approach neglects important information about system dynamics due to its reliance on the square modulus of the filter function. By decomposing the filter function while preserving phase information, we are able to separately consider contributions to x, y, and z rotations. This allows us to examine the controllability of a system under arbitrary driving fields, noise susceptibility, and their relationship to the geometric formalism.
Article
Materials Science, Multidisciplinary
MengKe Feng, Jun Yoneda, Wister Huang, Yue Su, Tuomo Tanttu, Chih Hwan Yang, Jesus D. Cifuentes, Kok Wai Chan, William Gilbert, Ross C. C. Leon, Fay E. Hudson, Kohei M. Itoh, Arne Laucht, Andrew S. Dzurak, Andre Saraiva
Summary: One of the key pathways to scaling up spin-based quantum computing systems is to achieve long-range interactions between electrons and increase their interconnectivity. Coherent spin transport is a promising strategy for achieving this architectural advantage. This theoretical study investigates possible sources of error in spin transport, such as tunnel coupling, magnetic field, and spin-orbit effects, and analyzes their impact on the spin transfer process. The findings highlight the importance of avoiding double dot configurations that exhibit enhanced decoherence for quantum information processing and provide insights for the future design of large-scale quantum processors.
Review
Computer Science, Information Systems
Tian Siang Ho, Harikrishnan Ramiah, Kishore Kumar Pakkirisami Churchill, Yong Chen, Chee Cheow Lim, Nai Shyan Lai, Pui-In Mak, Rui P. P. Martins
Summary: This article reviews the limitations of conventional SC-based charge pumps with fixed conversion ratio in energy harvesting systems and explores the feasibility of using SC-based reconfigurable charge pumps as alternative elements. The article provides a comprehensive overview of RCP structure and CP reconfigurable topologies, as well as design considerations for RCP in terms of dynamic range, PCE, and VCE.
Article
Computer Science, Information Systems
Mikki How-Wen Loo, Harikrishnan Ramiah, Ka-Meng Lei, Chee Cheow Lim, Nai Shyan Lai, Pui-In Mak, Rui P. Martins
Summary: This article examines recent publications on timers and classifies them into two major categories: open-loop-based and close-loop-based timers. It provides a comprehensive review from multiple perspectives and compares the characteristics of the two classes of timers.