Article
Multidisciplinary Sciences
C. F. Lo
Summary: In this study, we have demonstrated that the smallest possible single-qubit critical coupling strength of the N-qubit two-photon Rabi model is only 1/N times that of the two-photon Rabi model. At the critical coupling, the system not only has a set of discrete eigenenergies but also a continuous energy spectrum, which can be derived through a simple mapping to a bound state problem. The energy difference of each qubit determines the number of bound states available, providing insight into the extent of incomplete spectral collapse.
SCIENTIFIC REPORTS
(2021)
Article
Optics
Hiroki Sukeno, Tzu-Chieh Wei, Mark Hillery, Janos A. Bergou, Dov Fields, Vladimir S. Malinovsky
Summary: This work presents schemes to broadcast product and multipartite entangled quantum states using quantum entanglement assisted with measurements. It demonstrates the broadcasting of product quantum states in a network and the distribution of a single multiqubit state shared among several receivers entangled with multiqubit phase gates. The study shows the potential applications of broadcasting product states in cryptography and the distribution of the multiqubit Greenberger-Horne-Zeilinger state.
Article
Optics
Federico Andrea Sabattoli, Linda Gianini, Angelica Simbula, Marco Clementi, Antonio Fincato, Frederic Boeuf, Marco Liscidini, Matteo Galli, Daniele Bajoni
Summary: Researchers have successfully demonstrated an integrated source of frequency-entangled photon pairs on a silicon photonics chip, proving the existence of entanglement. This result opens up possibilities for on-chip integration of frequency-bin sources with other devices in the silicon photonics platform.
Article
Optics
Naoto Aizawa, Kazuya Niizeki, Riku Sasaki, Tomoyuki Horikiri
Summary: In this paper, a Sagnac-type spontaneous parametric down conversion system using a Fresnel rhomb as a wideband and reasonable retarder is proposed. It enables the generation of highly nondegenerate two-photon entanglement comprising the telecommunication wavelength and quantum memory wavelength. Quantum state tomography is performed to evaluate the degree of entanglement, and a fidelity of up to 94.4% with a Bell state |40+) is obtained. Therefore, this paper demonstrates the potential of nondegenerate EPSs compatible with both telecommunication wavelength and quantum-memory wavelength in quantum repeater architecture.
Article
Optics
Andrea T. Joseph, Roger Andrews
Summary: We studied the two-photon absorption properties of frequency-entangled N00N states in a Hong-Ou-Mandel interferometer, finding enhanced two-photon absorption due to frequency entanglement. We derived an analytic expression for the enhancement factor, which is greater than one for all finite values of the pump bandwidth to detected photons bandwidth ratio. Also, we observed suppression and enhancement in two-photon absorption probabilities for specific time delays applied to the N00N states.
Article
Physics, Multidisciplinary
Zhe Meng, Jiazhi Yang, Jian Li, Xiaoxiao Chen, Qingyuan Wu, Anning Zhang
Summary: This study proposes an AI algorithm that uses entangled photon pairs to compensate polarization, instead of high intensity reference laser. It opens up new possibilities for quantum communications and fundamental quantum optics experiments.
Article
Chemistry, Physical
Michael G. Raymer, Tiemo Landes, Andrew H. Marcus
Summary: This article explores the theoretical and experimental studies of two-photon absorption of molecules with time-frequency-entangled photon pairs and other nonlinear interactions, focused on handling the quantum nature of light. It combines basic quantum optics theory with density matrix derivation, emphasizing the use of entangled states and the enhancement of TPA. The article also compares TPA processes occurring via different intermediate states and discusses the challenges faced in experimental studies.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Physics, Multidisciplinary
Michael R. Geller
Summary: Several techniques have been introduced to mitigate errors in near-term quantum computers, focusing on gate errors and measurement errors. A widely used transition matrix error mitigation technique has limitations when state-preparation errors are present. A new measurement error mitigation technique, a conditionally rigorous TMEM, has been developed to address this issue and has been demonstrated on IBM Q superconducting qubits.
PHYSICAL REVIEW LETTERS
(2021)
Article
Quantum Science & Technology
Xiu Gu, Jorge Fernandez-Pendas, Pontus Vikstal, Tahereh Abad, Christopher Warren, Andreas Bengtsson, Giovanna Tancredi, Vitaly Shumeiko, Jonas Bylander, Goran Johansson, Anton Frisk Kockum
Summary: Near-term quantum computers are restricted to running low-depth quantum circuits due to the decoherence of qubits, limiting the types of quantum algorithms that can be implemented. By expanding the gate set to include multiqubit gates, it is possible to overcome these limitations and achieve gate fidelities above 99% in current quantum-computing platforms. Additionally, using simultaneous two-qubit gates allows for the swift creation of large entangled states like Dicke and Greenberger-Horne-Zeilinger states.
Article
Automation & Control Systems
Sen Kuang, Gan Li, Yanan Liu, Xiaqing Sun, Shuang Cong
Summary: This article proposes a rapid switching control scheme for stochastic quantum systems with measurement feedback, which can stabilize the eigenstate of an observable operator and achieve the preparation of entangled states in multiqubit systems. The strategy involves partitioning the state space and designing control laws to address convergence obstacles, leading to improved system trajectory and convergence speed.
IEEE TRANSACTIONS ON CYBERNETICS
(2022)
Article
Multidisciplinary Sciences
Bing Gu, Daniel Keefer, Flavia Aleotti, Artur Nenov, Marco Garavelli, Shaul Mukamel
Summary: This study demonstrates that two-photon excitation with quantum light can influence elementary photochemical events, with simulations showing how entangled two-photon excitation affects azobenzene trans -> cis isomerization. Photon entanglement modulates nuclear wave packets, influencing the reaction transition state and product yield. The distribution of vibronic coherences during conical intersection passage strongly depends on the initial wave packet shape upon quantum light excitation, with X-ray signals simulated for experimental monitoring.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Quantum Science & Technology
Youn Seok Lee, Mengyu Xie, Ramy Tannous, Thomas Jennewein
Summary: A novel method combining a Sagnac interferometer with a Mach-Zehnder interferometer was designed and implemented for generating polarization-entangled photon pairs. The versatile configuration achieved high-quality polarization and phase stability over a wide wavelength range using standard commercial optics. Experimentally, polarization entanglement was verified with a high visibility of 95.5% and the violation of the CHSH inequality, demonstrating the effectiveness of the novel approach.
QUANTUM SCIENCE AND TECHNOLOGY
(2021)
Article
Quantum Science & Technology
Sandeep Singh, Vimlesh Kumar, Anirban Ghosh, Andrew Forbes, G. K. Samanta
Summary: Researchers propose a novel system architecture based on a hybrid linear and non-linear solution, which enhances the tolerance of the source while maintaining brightness. This is achieved by utilizing a lens-axicon pair in combination with two common non-linear crystals, periodically-poled KTiOPO4 and birefringent-phase-matched BiB3O6. The proposed architecture demonstrates high spectral brightness and state fidelity, with enhanced tolerance compared to conventional SPDC configurations.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Chemistry, Multidisciplinary
Jinyong Ma, Jihua Zhang, Yuxin Jiang, Tongmiao Fan, Matthew Parry, Dragomir N. Neshev, Andrey A. Sukhorukov
Summary: We propose and demonstrate the preparation of desired two-photon polarization states using a nonlinear metasurface incorporating multiplexed silica metagratings on a lithium niobate film. The two-photon polarization states can be shaped by adjusting the metagrating orientation, and by combining multiple metagratings, arbitrary polarization-entangled qutrit states can be generated. This enables the miniaturization of optically controlled quantum devices using ultrathin metasurfaces as polarization-entangled photon sources.
Article
Chemistry, Multidisciplinary
Jinyong Ma, Jihua Zhang, Yuxin Jiang, Tongmiao Fan, Matthew Parry, Dragomir N. Neshev, Andrey A. Sukhorukov
Summary: The use of a nonlinear metasurface and a thin film allows for the flexible manipulation of complex polarization states of photon pairs. It is found that the orientation of the metagratings can shape the polarization states of the photon pairs. Additionally, combining three metagratings enables the generation of arbitrary polarization-entangled qutrit states.
Article
Radiology, Nuclear Medicine & Medical Imaging
Davide Brivio, Erno Sajo, Piotr Zygmanski
Article
Radiology, Nuclear Medicine & Medical Imaging
Davide Brivio, Erno Sajo, Piotr Zygmanski
Editorial Material
Radiology, Nuclear Medicine & Medical Imaging
D. Brivio, E. Sajo, P. Zygmanski
Article
Engineering, Biomedical
D. Brivio, P. L. Nguyen, E. Sajo, W. Ngwa, P. Zygmanski
PHYSICS IN MEDICINE AND BIOLOGY
(2017)
Article
Radiology, Nuclear Medicine & Medical Imaging
Davide Brivio, Steffen Albert, Erica Freund, Matt P. Gagne, Erno Sajo, Piotr Zygmanski
Article
Physics, Applied
Davide Brivio, Steffen Albert, Matt P. Gagne, Erica Freund, Erno Sajo, Piotr Zygmanski
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2020)
Article
Engineering, Biomedical
D. Brivio, E. Sajo, P. Zygmanski
Summary: The proposed MVIPE technique for detecting gold nanoparticles in therapeutic megavoltage x-ray beams shows a higher production of annihilation photons compared to XFCT. Coincidence counting in MVIPE allows for avoiding limitations seen in XFCT imaging.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Engineering, Biomedical
Robert Lauber, Davide Brivio, Erno Sajo, Juergen Hesser, Piotr Zygmanski
Summary: The purpose of this study is to evaluate the feasibility of a novel real-time beam monitoring device for medical linacs. The device is capable of remotely sensing charge carriers produced by the beam without intersecting and attenuating the beamline. The study focuses on developing a theoretical concept and physical model for the detector that can determine clinically relevant beam data in real time. A Least-Square approach is adopted to characterize the detector response and sensitivity for different electrode geometries and MLC shapes. Results show sub-mm accuracy in determining MLC leaf positions and quantified detector sensitivity in the pA to fA range.
PHYSICS IN MEDICINE AND BIOLOGY
(2022)
Article
Engineering, Biomedical
Piotr Zygmanski, Jason Lima, Arianna Liles, Victoria Zhang, Indre Gineitaite, Erno Sajo, Davide Brivio
Summary: We have developed a new type of detector array for monitoring radiation beams in radiotherapy. The detector has a parallel-plane architecture with multiple large-area uniform thin-film electrodes. The purpose of the study was to determine the detector's response to MLC collimated x-ray fields, and the results showed that the signal strength depends on the distance between the location of the pencil beam and the readouts and is quasi-linear with respect to MLC position.
PHYSICS IN MEDICINE AND BIOLOGY
(2022)
Article
Engineering, Biomedical
Steffen Albert, Davide Brivio, Saad Aldelaijan, Erno Sajo, Juergen Hesser, Piotr Zygmanski
PHYSICS IN MEDICINE AND BIOLOGY
(2020)
Meeting Abstract
Radiology, Nuclear Medicine & Medical Imaging
J. Kwon, D. Brivio, J. Mancias, C. -C. Cheng, F. Preiswerk, B. Madore, J. Bredfeldt
Meeting Abstract
Radiology, Nuclear Medicine & Medical Imaging
D. Brivio, S. Albert, L. Naumann, E. Sajo, P. Zygmanski
Meeting Abstract
Radiology, Nuclear Medicine & Medical Imaging
D. Brivio, M. Gagne, E. Freund, E. Sajo, P. Zygmanski
Article
Radiology, Nuclear Medicine & Medical Imaging
Davide Brivio, Yida David Hu, Danielle N. Margalit, Piotr Zygmanski
BIOMEDICAL PHYSICS & ENGINEERING EXPRESS
(2018)
Article
Nanoscience & Nanotechnology
Davide Brivio, Earl Ada, Erno Sajo, Piotr Zygmanski
ACS APPLIED MATERIALS & INTERFACES
(2017)
