Phys.org November 30, 2024 To enable parallel computations optical computing leverages interference, a cornerstone of quantum computing algorithms. Researchers in South Africa blended quantum computing with classical structured light by formulating the process of photonic matrix multiplication using quantum mechanical principles such as state superposition and demonstrated Deutsch–Jozsa’s algorithm, by elucidating the inherent tensor product structure within the Cartesian transverse degrees of freedom of light. They demonstrated the operation of a Hadamard gate. According to the researchers their approach show it is adaptable to various algorithms, and advances the use of structured light for quantum information processing… read more. Open […]
Tag Archives: Quantum computing
MIT physicists predict exotic form of matter with potential for quantum computing
MIT News November 18, 2024 Based on the recent discovery of fractional quantum anomalous Hall states in moiré systems, researchers at MIT studied a family of moiré systems, skyrmion Chern band models, which could be realized in two-dimensional semiconductor-magnet heterostructures and capture the essence of twisted transition metal dichalcogenide homobilayers. Using many-body exact diagonalization they showed that, despite strong Berry curvature variations in momentum space, the non-Abelian Moore-Read state could be realized at half filling of the second miniband. According to the researchers, their results demonstrate the feasibility of non-Abelian fractionalization in moiré systems without Landau levels and shed light […]
Superconductivity offers new insights into quantum material MnBiâ‚‚Teâ‚„
Phys.org October 23, 2024 Topological superconductors hosting Majorana zero modes are of great interest for both fundamental physics and potential quantum computing applications. Researchers in the Netherlands investigated the transport properties of the intrinsic magnetic topological insulator MnBi2Te4 (MBT). They found that the presence of chiral edge channels, though with deviations from perfect quantization due to factors such as non-uniform thickness, domain structures, and the presence of quasi-helical edge states. The fabricated superconducting junctions using niobium led on MBT exfoliated flakes, which showed an onset of supercurrent with clear Josephson coupling. The interference patterns in the superconducting junctions revealed interesting […]
Study unveils limits on the extent to which quantum errors can be ‘undone’ in large systems
Phys.org August 11, 2024 Recently quantum error mitigation has been successfully applied to reduce noise in near-term applications. However, an international team of researchers (Germany, USA – Harvard University, France) identified strong limitations to the degree to which quantum noise can be effectively ‘undone’ for larger system sizes. They developed a framework which rigorously captures large classes of error-mitigation schemes in use today. By relating error mitigation to a statistical inference problem, they showed that even at shallow circuit depths comparable to those of current experiments, a superpolynomial number of samples was needed in the worst case to estimate the […]
Understanding quantum states: New research shows importance of precise topography in solid neon qubits
Phys.org June 26, 2024 Single electrons trapped on solid-neon surfaces, which have long coherence times, are promising platform for charge qubits. The actual quantum states of the trapped electrons have not been understood. A team of researchers in the USA (National High Magnetic Field Laboratory (Florida), Florida State University, University of Florida, FAMU-FSU College of Engineering) examined the electron’s interactions with neon surface topography and by evaluating the surface charges induced by the electron, they demonstrated its strong perpendicular binding to the neon surface. They revealed that surface bumps could bind an electron, forming unique quantum ring states that aligned […]
Researchers develop compiler acceleration technology for quantum computers
Phys.org May 9, 2024 Researchers in Japan used a random search technique to find quantum gate sequences that implement perfect quantum state preparation or unitary operator synthesis with arbitrary targets. The approach was based on the recent discovery that there is a large multiplicity of quantum circuits that achieved unit fidelity in performing a given target operation, even at the minimum number of single-qubit and two-qubit gates needed to achieve unit fidelity. They showed that the fraction of perfect-fidelity quantum circuits increased rapidly as soon as the circuit size exceeded the minimum circuit size required for achieving unit fidelity. This […]
Compact quantum light processing: New findings lead to advances in optical quantum computing
Phys.org April 19, 2024 The polarization of single photons are used as addressable degrees of freedom for turning the interference of nonclassical states of light into practical applications. However, the scale-up for the processing of a large number of photons of these architectures is very resource-demanding due to the rapidly increasing number of components, such as optical elements, photon sources, and detectors. An international team of researchers (Austria, Italy, Belgium) demonstrated a resource-efficient architecture for multiphoton processing based on time-bin encoding in a single spatial mode. They used an efficient quantum dot single-photon source and a fast programmable time-bin interferometer […]
New research area promotes both quantum computing and cognitive science
Phys.org March 26, 2024 Quantum biology applies quantum mechanics to biological systems at the molecular scale. Molecular quantum computing explores the degrees of freedom of molecules that can be used to produce quantum coherence. Cognitive science focuses on understanding how learning processes are realized, particularly within the human brain. An international team of researchers (US, USA – New Jersey Institute of Technology, Morgan State University) reviewed progress in quantum biology, molecular quantum computing, and quantum theory in cognitive science. Based on their analysis and review, they highlighted that molecular quantum computing could be an important bridging research area between quantum […]
New ion cooling technique could simplify quantum computing devices
Phys.org February 6, 2024 In current QCCD implementations, imperfect ion transport and anomalous heating can excite ion motion during a calculation. To counteract this, intermediate cooling is necessary to maintain high-fidelity gate performance. Cooling the computational ions sympathetically with ions of another species creates a significant runtime bottleneck. Researchers at the Georgia Institute of Technology demonstrated exchange cooling which does not require trapping two different atomic species. They introduced a bank of “coolant” ions which were repeatedly laser cooled. A computational ion could be cooled by transporting a coolant ion into its proximity. Experimentally they tested this concept and executed […]
Microsoft claims to have achieved first milestone in creating a reliable and practical quantum computer
Phys.org. June 24, 2023 Researchers at Microsoft (USA) engineered a new way to represent a logical qubit with hardware stability. They reported that the device could induce a phase of matter characterized by Majorana zero modes, such devices have demonstrated low enough disorder to pass the topological gap protocol, proving the technology is viable. They stated that it has created a new measure to gauge the performance of a quantum supercomputer: reliable quantum operations per second (rope), a figure that describes how many reliable operations a computer can execute in a single second. They suggest that for a machine to […]