Article
Multidisciplinary Sciences
C. G. L. Bottcher, S. P. Harvey, S. Fallahi, G. C. Gardner, M. J. Manfra, U. Vool, S. D. Bartlett, A. Yacoby
Summary: This study demonstrates a controllable spin-photon coupling based on a longitudinal interaction, enabling remote entangling operations in a quantum computer. By driving a singlet-triplet qubit near the resonator frequency, a longitudinal coupling with a high-impedance superconducting resonator is achieved. The energy splitting of the qubit is measured as a function of the drive amplitude and frequency, showing pronounced effects near the resonator frequency due to longitudinal coupling.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Michael T. Jones, Md Serajum Monir, Felix N. Krauth, Pascal Macha, Yu-Ling Hsueh, Angus Worrall, Joris G. Keizer, Ludwik Kranz, Samuel K. Gorman, Yousun Chung, Rajib Rahman, Michelle Y. Simmons
Summary: This study demonstrates a platform for quantum computing using phosphorus donor atoms in silicon. By adjusting the arrangement and spacing of the donor atoms, the speed and accuracy of qubit gates can be improved without affecting neighboring qubits. This approach provides a new pathway for achieving high fidelity and scalable quantum computing.
Article
Multidisciplinary Sciences
M. H. Abobeih, Y. Wang, J. Randall, S. J. H. Loenen, C. E. Bradley, M. Markham, D. J. Twitchen, B. M. Terhal, T. H. Taminiau
Summary: Solid-state spin qubits have shown promise in quantum computation and quantum networks. Recent experiments have demonstrated high-quality control over multi-qubit systems, elementary quantum algorithms, and non-fault-tolerant error correction. This study demonstrates fault-tolerant operations on a logical qubit using spin qubits in diamond, paving the way for reliable quantum information processing.
Article
Multidisciplinary Sciences
Nico W. Hendrickx, William I. L. Lawrie, Maximilian Russ, Floor van Riggelen, Sander L. de Snoo, Raymond N. Schouten, Amir Sammak, Giordano Scappucci, Menno Veldhorst
Summary: Research on building quantum circuits using advanced semiconductor manufacturing techniques has led to the demonstration of a four-qubit quantum processor based on hole spins in germanium quantum dots. All-electric qubit logic allows for freely programmable operations on multiple qubits, resulting in a compact and highly connected circuit. The results are a step towards quantum error correction and quantum simulation using quantum dots.
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
Physics, Applied
Ethan A. Scott, Christopher M. Smyth, Manish K. Singh, Tzu-Ming Lu, Peter Sharma, Douglas Pete, John Watt, C. Thomas Harris
Summary: Gold-germanium solid solutions show high sensitivity as thin film thermometers. This study investigates the performance of films with thicknesses less than 100 nm. The results demonstrate that ultra-thin films with thickness as low as 10 nm exhibit enhanced temperature sensitivity, making them suitable for high-sensitivity on-device thermometers in micro- and nanolectromechanical systems.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Quantum Science & Technology
Veit Langrock, Jan A. Krzywda, Niels Focke, Inga Seidler, Lars R. Schreiber, Lukasz Cywinski
Summary: Silicon spin qubits have long coherence times, are compatible with industrial fabrication, and contain the potential to integrate classical control electronics. A blueprint for a coherent mid-range link, called a spin qubit shuttle, has been presented to address the signal fan-out problem between qubit registers. The shuttle consists of an array of gates connected into sets, requiring only a few voltage control lines to control these sets, and is independent of the length of the link. Two operation modes, qubit conveyor and bucket brigade, have been discussed, with the former being more viable in a realistic Si/SiGe device. Transfer fidelity of 99.9% is feasible at a speed of approximately 10 m/s, given realistic bounds on valley splitting and its inhomogeneity.
Article
Multidisciplinary Sciences
Adam R. Mills, Charles R. Guinn, Michael J. Gullans, Anthony J. Sigillito, Mayer M. Feldman, Erik Nielsen, Jason R. Petta
Summary: Silicon spin qubits have the potential to become the dominant technology in the development of intermediate-scale quantum processors. However, there are still shortcomings in achieving high-fidelity state preparation and readout, as well as single- and two-qubit gate operations.
Review
Materials Science, Ceramics
Abanti Nag, R. Ramachandra Rao, P. K. Panda
Summary: Radome, an enclosure for radar antenna in military aircraft and missiles, is classified based on function type and operation speed. While composite laminates are suitable for subsonic applications, ceramics are the only option for high-speed military aerospace applications. Silicon nitride based radome materials with controlled porosity are proposed as futuristic high temperature materials for supersonic applications.
CERAMICS INTERNATIONAL
(2021)
Article
Multidisciplinary Sciences
Rostyslav Savytskyy, Tim Botzem, Irene Fernandez de Fuentes, Benjamin Joecker, Jarryd J. Pla, Fay E. Hudson, Kohei M. Itoh, Alexander M. Jakob, Brett C. Johnson, David N. Jamieson, Andrew S. Dzurak, Andrea Morello
Summary: The spins of atoms and atom-like systems, which store quantum information, can now be controlled using local electric fields without the need for oscillating magnetic fields. This breakthrough was achieved by operating a single-atom flip-flop qubit in silicon, where quantum information is encoded in the electron-nuclear states of a phosphorus donor. This method, which modulates the electron-nuclear hyperfine coupling, can be extended to other atomic and molecular systems and enable the hyperpolarization of nuclear spin ensembles.
Article
Physics, Multidisciplinary
Morteza Mohseni, Vitaliy I. Vasyuchka, Victor S. L'vov, Alexander A. Serga, Burkard Hillebrands
Summary: This work focuses on classical analogs for quantum computing schemes, demonstrating the manipulation of a magnon condensate using wavevector-selective parametric pumping. It shows the possibility of Rabi-like oscillations in the wavevector domain and provides a significant stimulus in the field of qubit functionality and classical systems.
COMMUNICATIONS PHYSICS
(2022)
Article
Physics, Multidisciplinary
Brennan Undseth, Oriol Pietx-Casas, Eline Raymenants, Mohammad Mehmandoost, Mateusz T. Madzik, Stephan G. J. Philips, Sander L. de Snoo, David J. Michalak, Sergey V. Amitonov, Larysa Tryputen, Brian Paquelet Wuetz, Viviana Fezzi, Davide Degli Esposti, Amir Sammak, Giordano Scappucci, Lieven M. K. Vandersypen
Summary: As spin-based quantum processors grow in size and complexity, maintaining high fidelities and minimizing crosstalk are crucial for successful quantum algorithms and error-correction protocols. This study makes significant progress in understanding and overcoming the detrimental effects of microwave qubit driving on qubit frequency shifts. Operating the device at 200 mK effectively suppresses adverse heating effects without compromising qubit coherence or fidelity benchmarks. Furthermore, systematic non-Markovian crosstalk is greatly reduced.
Article
Quantum Science & Technology
Zhanjun Zhang, Hao Yuan
Summary: The scheme proposes the sharing of a single-qubit operation on a remote target state using a five-qubit cluster state in a given entanglement structure as a quantum channel. It offers advantages such as 100% success rate, arbitrary operation sharing, and relatively economic resource consumption, while revealing the underlying physical essence through deep studies. Discussions on security and analysis of experimental feasibility are also included.
QUANTUM INFORMATION PROCESSING
(2021)
Article
Engineering, Electrical & Electronic
Meng Xun, Guanzhong Pan, Zhuang Zhuang Zhao, Yun Sun, Jingtao Zhou, Dexin Wu
Summary: High-efficiency vertical cavity surface-emitting lasers (VCSELs) operating in continuous wave (CW) mode achieve lasing at temperatures greater than 190 degrees C. The maximum power conversion efficiency (PCE) of 46.3% is demonstrated at 30 degrees C ambient temperature, with only a 10% decrease in PCE from 30 degrees C to 90 degrees C. The thermal characteristics and mode operation of the VCSELs are stable even at high temperatures, showing potential for future laser radar applications.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Optics
Junhua Dong, Bingsuo Zou, Yongyou Zhang
Summary: This article proposes a reconfigurable valley topological quantum electrodynamics (QED) platform scheme based on the honeycomb lattice of Jaynes-Cummings emitters, which can be implemented by cavity-or circuit-QED cells. Based on this reconfigurable platform, a tunable topological quantum router is designed and the theory of achieving topological quantum storage and reading is demonstrated. Both of these signify the remarkable potential of the suggested reconfigurable topological QED platform for qubit operation.
Article
Nanoscience & Nanotechnology
Takuya Iwasaki, Kosuke Endo, Eiichiro Watanabe, Daiju Tsuya, Yoshifumi Morita, Shu Nakaharai, Yutaka Noguchi, Yutaka Wakayama, Kenji Watanabe, Takashi Taniguchi, Satoshi Moriyama
ACS APPLIED MATERIALS & INTERFACES
(2020)
Article
Physics, Applied
Takuya Iwasaki, Taku Kato, Hirohito Ito, Kenji Watanabe, Takashi Taniguchi, Yutaka Wakayama, Tsuyoshi Hatano, Satoshi Moriyama
JAPANESE JOURNAL OF APPLIED PHYSICS
(2020)
Article
Physics, Applied
Yosuke Sasama, Taisuke Kageura, Katsuyoshi Komatsu, Satoshi Moriyama, Jun-ichi Inoue, Masataka Imura, Kenji Watanabe, Takashi Taniguchi, Takashi Uchihashi, Yamaguchi Takahide
JOURNAL OF APPLIED PHYSICS
(2020)
Article
Chemistry, Multidisciplinary
Takuya Iwasaki, Shu Nakaharai, Yutaka Wakayama, Kenji Watanabe, Takashi Taniguchi, Yoshifumi Morita, Satoshi Moriyama
Article
Multidisciplinary Sciences
Kota Kato, Tasuku Takagi, Takasumi Tanabe, Satoshi Moriyama, Yoshifumi Morita, Hideyuki Maki
SCIENTIFIC REPORTS
(2020)
Article
Physics, Applied
Yoshisuke Ban, Kimihiko Kato, Shota Iizuka, Satoshi Moriyama, Koji Ishibashi, Keiji Ono, Takahiro Mori
Summary: The experimental study demonstrated that introducing beryllium as an isoelectronic trap into the channel of Si tunnel FETs can significantly enhance the ON current and suppress variability. The Be-introduced TFET showed a five times enhancement in ON current compared to the Al-N IET, and also successfully reduced variability. The deeper energy level of Be compared to Al-N IET played a key role in improving the performance of Si-TFETs.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
Takuya Iwasaki, Shu Nakamura, Osazuwa G. Agbonlahor, Manoharan Muruganathan, Masashi Akabori, Yoshifumi Morita, Satoshi Moriyama, Shinichi Ogawa, Yutaka Wakayama, Hiroshi Mizuta, Shu Nakaharai
Summary: The study focuses on Anderson localization in Dirac materials and the strong and weak localization phenomena in specific graphene. Negative magnetoresistance was achieved through helium ion irradiation, and for the first time, negative magnetoresistance in graphene devices was observed at room temperature.
Article
Multidisciplinary Sciences
Takuya Iwasaki, Satoshi Moriyama, Nurul Fariha Ahmad, Katsuyoshi Komatsu, Kenji Watanabe, Takashi Taniguchi, Yutaka Wakayama, Abdul Manaf Hashim, Yoshifumi Morita, Shu Nakaharai
Summary: We report on the magnetotransport characteristics of a high-quality graphene device encapsulated in hexagonal boron nitride layers, showing an interplay of quantum interferences in Dirac materials at different temperatures. The elastic scattering mechanism in the hBN/Gr/hBN stacks contrasts with conventional graphene on SiO2, and our ultra-clean graphene device exhibits nonzero magnetoconductance at high temperatures up to 300 K.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Applied
Yoshisuke Ban, Kimihiko Kato, Shota Iizuka, Shigenori Murakami, Koji Ishibashi, Satoshi Moriyama, Takahiro Mori, Keiji Ono
Summary: In order to achieve high-temperature operation of Si qubits, deep impurity levels with large confinement energy were introduced into Si wafers to minimize thermal excitation. Group II impurity Zn and group VI impurities S and Se were introduced into Si substrates using ion implantation, known for forming deep levels. The concentration-depth profiles, energy level depths, and absence of defects of these samples were analyzed. Conditions for introducing deep impurities into 50 nm thick Si channels were identified, and the formation of deep levels and absence of defects were experimentally confirmed. Using the obtained conditions, single-electron transport at room temperature, high-temperature operation of qubits, and room-temperature quantum magnetic sensors are promising.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Shu Nakaharai, Takuya Iwasaki, Yoshifumi Morita, Satoshi Moriyama, Shinichi Ogawa
Summary: This article reviews the charge carrier transport phenomena in single-layer graphene with crystalline defects generated by helium-ion-beam irradiation. It demonstrates the real-time conductivity monitoring during ion beam scans over the graphene surface and explores the unique properties and localization phenomena of defective graphene under magnetic fields. It also showcases the fabrication and operation of field-effect transistors using defective graphene channels.
Article
Chemistry, Multidisciplinary
Seiya Suzuki, Takuya Iwasaki, K. Kanishka H. De Silva, Shigeru Suehara, Kenji Watanabe, Takashi Taniguchi, Satoshi Moriyama, Masamichi Yoshimura, Takashi Aizawa, Tomonobu Nakayama
Summary: Germanene, a 2D honeycomb germanium crystal, is grown at graphene/Ag(111) and hexagonal boron nitride (h-BN)/Ag(111) interfaces by segregating germanium atoms. A simple annealing process in N-2 or H-2/Ar at ambient pressure leads to the formation of germanene, indicating that an ultrahigh-vacuum condition is not necessary. The grown germanene is stable in air and uniform over the entire area covered with a van der Waals (vdW) material.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Chanchal Chakraborty, Utpal Rana, Yemineni S. L. Narayana, Satoshi Moriyama, Masayoshi Higuchi
ACS APPLIED POLYMER MATERIALS
(2020)
Article
Physics, Multidisciplinary
K. Ono, S. N. Shevchenko, T. Mori, S. Moriyama, Franco Nori
PHYSICAL REVIEW LETTERS
(2020)
Article
Materials Science, Multidisciplinary
Chanchal Chakraborty, Utpal Rana, Satoshi Moriyama, Masayoshi Higuchi
ACS APPLIED POLYMER MATERIALS
(2020)
Article
Physics, Applied
Takuya Iwasaki, Yoshifumi Morita, Shu Nakaharai, Yutaka Wakayama, Eiichiro Watanabe, Daiju Tsuya, Kenji Watanabe, Takashi Taniguchi, Satoshi Moriyama
APPLIED PHYSICS EXPRESS
(2020)