Article
Physics, Multidisciplinary
Zhongqing Ji, Jie Fan, Jing Dong, Yongbo Bian, Zhi-Gang Cheng
Summary: Low temperature environments are crucial for studies in condensed matter physics and quantum technologies. Dilution refrigeration is the most reliable method to create and maintain ultra-low temperatures. Cryogen-free dilution refrigerators have become the main alternative to traditional systems.
Article
Instruments & Instrumentation
Jiaojie Yan, Jianing Yao, Vladimir Shvarts, Rui-Rui Du, Xi Lin
Summary: A temperature below 100 mu K is achieved using a customized cryogen-free dilution refrigerator with a copper-nuclear demagnetization stage. The lowest temperature of conduction electrons is measured by a pulsed platinum nuclear magnetic resonance thermometer, and can remain below 100 mu K for over 10 hours. The demagnetization magnetic field and research magnetic field can be controlled independently, provided by a coaxial room-temperature-bore cryogen-free magnet.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Multidisciplinary Sciences
Ryan M. Jock, N. Tobias Jacobson, Martin Rudolph, Daniel R. Ward, Malcolm S. Carroll, Dwight R. Luhman
Summary: This research demonstrates a method for controlling electron spin qubits on a silicon heterointerface through spin-orbit effects, without the need for complex nanofabrication equipment. The method offers high logic gate orthogonality and long qubit coherence time, while enabling fast control. The study also investigates charge noise in a silicon double quantum dot through dynamical decoupling experiments and evaluates qubit frequency drift and low-frequency noise.
NATURE COMMUNICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Leon C. Camenzind, Simon Geyer, Andreas Fuhrer, Richard J. Warburton, Dominik M. Zumbuehl, Andreas Kuhlmann
Summary: The greatest challenge in quantum computing is achieving scalability. However, silicon fin field-effect transistors can host spin qubits operating above 4 K, potentially enabling the scaling and development of quantum computing systems.
NATURE ELECTRONICS
(2022)
Article
Instruments & Instrumentation
Jun Kasai, Tomoki Koyama, Munenori Yokota, Katsuya Iwaya
Summary: We present the design and performance of a cryogen-free, pulse-tube refrigerator (PTR)-based scanning probe microscopy (SPM) system, capable of operating at a base temperature close to 5 K. By improving the interface design and gas-handling system, the SPM system achieves comparable performance to traditional liquid-helium-based systems, without the need for cryogen refills.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Instruments & Instrumentation
S. M. Fleischer, M. P. Ross, K. Venkateswara, C. A. Hagedorn, E. A. Shaw, E. Swanson, B. R. Heckel, J. H. Gundlach
Summary: This article introduces a liquid-cryogen free cryostat that allows for continuous operation of a torsion balance at cryogenic temperatures. By using a two-stage pulse-tube cooler and passive vibration isolation, the torsion balance exhibits lower torque noise levels than room temperature thermal noise. However, the accumulation of cryogenic surface contamination on the optical elements inside the cryostat limits the maximum duration of a continuous measurement run.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Materials Science, Multidisciplinary
F. Fehse, M. David, M. Pioro-Ladriere, W. A. Coish
Summary: Population-transfer schemes are widely used to convert stored quantum information into measurable macroscopic degrees of freedom. However, the adiabatic nature of these schemes and the accumulation of errors through dephasing, leakage, and energy relaxation processes limit the fidelity that can be achieved. Here, we propose fast quasiadiabatic conversion strategies beyond the adiabatic approximation that take noise into account and allow for optimal state conversion.
Article
Chemistry, Multidisciplinary
Richard Monge, Tom Delord, Nicholas V. Proscia, Zav Shotan, Harishankar Jayakumar, Jacob Henshaw, Pablo R. Zangara, Artur Lozovoi, Daniela Pagliero, Pablo D. Esquinazi, Toshu An, Inti Sodemann, Vinod M. Menon, Carlos A. Meriles
Summary: A broad effort is being made to understand and utilize the interaction between superconductors and spin-active color centers, with the goal of hybrid quantum devices and novel imaging techniques for superconducting materials. However, most work ignores the interplay between either system and the environment created by the color center host. In this study, a diamond scanning probe is used to investigate the spin dynamics of a single nitrogen-vacancy (NV) center near a superconducting film. The presence of the superconductor is found to increase the NV spin coherence lifetime, which may be attributed to a change in the electric noise caused by a redistribution of charge carriers due to the superconductor. These findings not only shed light on the dynamics of shallow NV spin coherence, but also offer new possibilities for noise spectroscopy and imaging of superconductors.
Article
Optics
Hongting Song, Areeya Chantasri, Behnam Tonekaboni, Howard M. Wiseman
Summary: Spectator qubits (SQs) are used to reduce noise in inaccessible data qubits. SQs, which are more sensitive to noise, are measured frequently and the results are rarely used to correct data qubits. A Bayesian method utilizing complex linear maps is introduced to address dephasing from random telegraph noise, which results in an optimally adaptive measurement and control protocol. The decoherence rate suppression is quadratic in the sensitivity of the SQ, demonstrating that the SQ paradigm works well in the appropriate regime.
Article
Nanoscience & Nanotechnology
Seong Woo Oh, Artem O. Denisov, Pengcheng Chen, Jason R. Petta
Summary: Silicon can be isotopically enriched for highly coherent semiconductor spin qubits, but the six-fold valley degeneracy in bulk Si may affect silicon quantum devices. A cryogen-free scanning gate microscope for Si/Si0.7Ge0.3 quantum devices at mK temperatures was developed, capable of forming and measuring quantum dots without compromising quantum control experiments. Vibration noise reduction techniques were implemented to achieve precise characterization of fully functioning Si/Si0.7Ge0.3 quantum devices.
Article
Automation & Control Systems
Yusuf Yasa, Yilmaz Sozer, Muhammet Garip
Summary: This article proposes the insertion of a leaf spring into the stator back iron to reduce vibration and noise in a switched reluctance machine (SRM). The effectiveness of the leaf spring in dampening radial force harmonic orders is confirmed through simulation and experimental results.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Shuvajit Das, Omer Gundogmus, Yilmaz Sozer, John Kutz, Joshua Tylenda, Ronnie L. Wright
Summary: The article addresses the noise, vibration, and harshness issue in switched reluctance machines (SRMs) by proposing a structural design modification in the stator to increase stiffness to mass ratio. The study focuses on a 24-slot 16-pole SRM designed for automotive applications and tackles the average torque reduction due to flux shorting in stator pole bridges by using a low-permeability material. Experimental results show a maximum noise reduction of 12.52 dBA in the stator pole bridge model compared to the baseline SRM.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Materials Science, Multidisciplinary
David C. Harrison, E. Dan Dahlberg, Raymond L. Orbach
Summary: The temperature and frequency dependence of 1/f resistance noise in thin CuMn spin-glass films has been studied, revealing a distribution of free-energy barriers that change with temperature.
Article
Green & Sustainable Science & Technology
Ying Hao, Haifeng Qi, Shengchun Liu, Victor Nian, Zhongyao Zhang
Summary: The developments in urban rail transit construction bring both benefits and negative impacts. This study focuses on the field measurement of indoor vibration and noise spectrum near urban rapid transit lines in Tianjin, China. The effectiveness of mitigation measures, such as wheel-rail polishing and train speed reduction, was evaluated. The study found that the effectiveness of noise and vibration reduction depends on the attenuation of the main frequency corresponding to the secondary radiation noise in buildings.
Article
Automation & Control Systems
Omer Gundogmus, Shuvajit Das, Yusuf Yasa, Mohammed Elamin, Yilmaz Sozer, John Kutz, Joshua Tylenda, Ronnie L. Wright
Summary: This work explores the analysis and experimental validation of using skewing to reduce acoustic noise in a high pole count, high power switched reluctance machine (SRM). The results show that skewing both the stator and rotor by the same amount has superior electromagnetic performance and can significantly reduce noise.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2022)
Article
Chemistry, Multidisciplinary
Kok Wai Chan, Harshad Sahasrabudhe, Wister Huang, Yu Wang, Henry C. Yang, Menno Veldhorst, Jason C. C. Hwang, Fahd A. Mohiyaddin, Fay E. Hudson, Kohei M. Itoh, Andre Saraiva, Andrea Morello, Arne Laucht, Rajib Rahman, Andrew S. Dzurak
Summary: Quantum gates between spin qubits can be implemented through controlled Heisenberg exchange interaction by adjusting the overlap between electronic wave functions. Another approach is to establish coupling between distant spins through mediated superexchange. Experimental evidence in a linear array of three single-electron spin qubits in silicon confirms direct exchange coupling and second neighbor mediated superexchange.
Article
Multidisciplinary Sciences
Mateusz T. Madzik, Arne Laucht, Fay E. Hudson, Alexander M. Jakob, Brett C. Johnson, David N. Jamieson, Kohei M. Itoh, Andrew S. Dzurak, Andrea Morello
Summary: Researchers demonstrate conditional, coherent control of electron spin qubits in exchange-coupled pairs of P-31 donors implanted in silicon, achieving a local two-qubit controlled-rotation gate with high precision through spectroscopic measurement of the coupling strength.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Alexander M. Jakob, Simon G. Robson, Vivien Schmitt, Vincent Mourik, Matthias Posselt, Daniel Spemann, Brett C. Johnson, Hannes R. Firgau, Edwin Mayes, Jeffrey C. McCallum, Andrea Morello, David N. Jamieson
Summary: This study discusses the material choice of silicon chips containing arrays of single dopant atoms for classical and quantum devices, as well as the method of near-surface implantation of single ions and the associated physics model and limiting factors.
ADVANCED MATERIALS
(2022)
Article
Multidisciplinary Sciences
Mateusz T. Madzik, Serwan Asaad, Akram Youssry, Benjamin Joecker, Kenneth M. Rudinger, Erik Nielsen, Kevin C. Young, Timothy J. Proctor, Andrew D. Baczewski, Arne Laucht, Vivien Schmitt, Fay E. Hudson, Kohei M. Itoh, Alexander M. Jakob, Brett C. Johnson, David N. Jamieson, Andrew S. Dzurak, Christopher Ferrie, Robin Blume-Kohout, Andrea Morello
Summary: This study demonstrates universal quantum logic operations using nuclear spins in a silicon nanoelectronic device, achieving high-fidelity entangled states. The precise characterization of quantum operations shows that nuclear spins are approaching the performance required for fault-tolerant quantum processors. Additionally, the entanglement between nuclear spins and electron spins is also demonstrated. The results establish a viable route for scalable quantum information processing using donor nuclear and electron spins.
Article
Physics, Applied
Daniel J. Parker, Mykhailo Savytskyi, Wyatt Vine, Arne Laucht, Timothy Duty, Andrea Morello, Arne L. Grimsmo, Jarryd J. Pla
Summary: Degenerate parametric amplifiers (DPAs) exhibit phase-sensitive gain and have been utilized in various applications. This study investigates a microwave DPA utilizing nonlinearity from kinetic inductance with high dynamic range and squeezing potential. The amplifier shows promising performance near quantum noise limit and minimal higher-order nonlinearities, making it a potential candidate for future applications.
PHYSICAL REVIEW APPLIED
(2022)
Article
Engineering, Electrical & Electronic
A. M. J. Zwerver, T. Krahenmann, T. F. Watson, L. Lampert, H. C. George, R. Pillarisetty, S. A. Bojarski, P. Amin, S. Amitonov, J. M. Boter, R. Caudillo, D. Corras-Serrano, J. P. Dehollain, G. Droulers, E. M. Henry, R. Kotlyar, M. Lodari, F. Luthi, D. J. Michalak, B. K. Mueller, S. Neyens, J. Roberts, N. Samkharadze, G. Zheng, O. K. Zietz, G. Scappucci, M. Veldhorst, L. M. K. Vandersypen, J. S. Clarke
Summary: Silicon spin qubits can be fabricated using optical lithography and industrial processing in a 300 mm semiconductor manufacturing facility. This approach allows for the production of nanoscale gate patterns with high yield. The quantum dots exhibit good tunnel barrier control, making them suitable for fault-tolerant two-qubit gates.
NATURE ELECTRONICS
(2022)
Correction
Engineering, Electrical & Electronic
A. M. J. Zwerver, T. Krahenmann, T. F. Watson, L. Lampert, H. C. George, R. Pillarisetty, S. A. Bojarski, P. Amin, S. V. Amitonov, J. M. Boter, R. Caudillo, D. Correas-Serrano, J. P. Dehollain, G. Droulers, E. M. Henry, R. Kotlyar, M. Lodari, F. Luthi, D. J. Michalak, B. K. Mueller, S. Neyens, J. Roberts, N. Samkharadze, G. Zheng, O. K. Zietz, G. Scappucci, M. Veldhorst, L. M. K. Vandersypen, J. S. Clarke
NATURE ELECTRONICS
(2022)
Article
Physics, Multidisciplinary
Mark A. Johnson, Mateusz T. Madzik, Fay E. Hudson, Kohei M. Itoh, Alexander M. Jakob, David N. Jamieson, Andrew Dzurak, Andrea Morello
Summary: This article presents a method for initializing quantum states with a fidelity beyond the thermal limit using real-time monitoring and negative-result measurement. The experimental results show that this method can reduce initialization errors and improve fidelity by increasing the bandwidth of the amplifier chain or slowing down electron tunneling rates.
Article
Physics, Applied
S. G. Robson, P. Raecke, A. M. Jakob, N. Collins, H. R. Firgau, V Schmitt, V Mourik, A. Morello, E. Mayes, D. Spemann, D. N. Jamieson
Summary: This study explores a feasible approach to create large-scale donor arrays in silicon devices by implanting low-energy ions and evaluating the device response characteristics using a specific characterization system.
PHYSICAL REVIEW APPLIED
(2022)
Article
Physics, Applied
Jelmer M. Boter, Juan P. Dehollain, Jeroen P. G. van Dijk, Yuanxing Xu, Toivo Hensgens, Richard Versluis, Henricus W. L. Naus, James S. Clarke, Menno Veldhorst, Fabio Sebastiano, Lieven M. K. Vandersypen
Summary: This article discusses a quantum-dot spin-qubit architecture that integrates on-chip control electronics, reducing the number of signal connections at the chip boundary. It presents a concrete floor plan and estimates the operation frequencies and power consumption of a million-qubit array. This work significantly closes the gap towards a fully CMOS-compatible quantum computer implementation.
PHYSICAL REVIEW APPLIED
(2022)
Article
Materials Science, Multidisciplinary
Teemu Loippo, Antti Kanniainen, Juha T. Muhonen
Summary: Donor spin states in silicon are being considered for quantum information processing and bound exciton transitions are a potential readout mechanism. In this study, we investigate the effects of strain on phosphorus donor bound exciton transitions using hybrid electro-optical readout with microfabricated electrodes. We observe significant zero-field splitting and mixing of hole states due to strain, but these effects should not hinder donor electron spin readout. The findings suggest that hybrid spin readout could be possible on a silicon-on-insulator platform, allowing integration into silicon photonics platforms.
PHYSICAL REVIEW MATERIALS
(2023)
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
Physics, Applied
Giada R. La Gala, Arvind Shankar Kumar, Rick Leijssen, Ewold Verhagen, Juha T. Muhonen
Summary: Balanced homodyne interferometry is a widely used technique for detecting and characterizing light fields with high sensitivity. Traditionally, a homodyne interferometer locks the relative phase between a reference beam and a signal beam using an active feedback loop. However, an alternative method of averaging all relative phases by modulating the reference beam arm length has been shown to be advantageous for estimating the parameters of an optical cavity. This approach does not require active feedback, provides easy interpretation of results, and allows characterization of absolute magnitude of cavity frequency modulation.
PHYSICAL REVIEW APPLIED
(2023)
Article
Optics
Philip Daniel Blocher, Serwan Asaad, Vincent Mourik, Mark A. Johnson, Andrea Morello, Klaus Molmer
Summary: Out-of-time-ordered correlation functions (OTOCs) are crucial in studying quantum information scrambling, but are difficult to measure experimentally. This study proposes an OTOC measurement protocol that does not rely on time reversal and is applicable to various experimental settings and systems.
