Quantum states

Researchers control quantum states with spin-polarized currents

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Researchers at ETH Zurich have achieved a significant breakthrough in quantum physics by demonstrating that quantum states of single electron spins can be controlled using spin-polarized electron currents. This pioneering method holds potential for future applications in electronic circuit elements, potentially revolutionizing data storage and processing. The Spin of Electrons Electrons possess an intrinsic angular … Read more

New method for quieting the quantum world

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One of the biggest challenges in quantum technology and quantum sensing is “noise”–seemingly random environmental disturbances that can disrupt the delicate quantum states of qubits, the fundamental units of quantum information. Looking deeper at this issue, JILA Associate Fellow and University of Colorado Boulder Physics Assistant Professor Shuo Sun collaborated with Andrés Montoya-Castillo, Assistant Professor … Read more

Creation of a stable Bose-Einstein condensate from sodium-cesium molecules

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There’s a hot new BEC in town that has nothing to do with bacon, egg, and cheese. You won’t find it at your local bodega, but in the coldest place in New York: the lab of Columbia physicist Sebastian Will, whose experimental group specializes in pushing atoms and molecules to temperatures just fractions of a … Read more

New approach uses non-gaussian states to describe and control spin-boson systems in quantum devices

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Many of today’s quantum devices rely on collections of qubits, also called spins. These quantum bits have only two energy levels, the “0” and the “1.” However, spins in real devices also interact with light and vibrations known as bosons, greatly complicating calculations. In a new publication in Physical Review Letters, researchers in Amsterdam demonstrate … Read more

Miniaturized quantum light detector paves way for scalable quantum technologies

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Researchers at the University of Bristol have made an important breakthrough in scaling quantum technology by integrating the world’s tiniest quantum light detector onto a silicon chip. The paper, “A Bi-CMOS electronic photonic integrated circuit quantum light detector,” was published in Science Advances. A critical moment in unlocking the information age was when scientists and engineers … Read more

New study demonstrates momentum-exchange interaction to overcome atomic recoil

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Precisely measuring the energy states of individual atoms has been a historical challenge for physicists due to atomic recoil. When an atom interacts with a photon, the atom “recoils” in the opposite direction, making it difficult to measure the position and momentum of the atom precisely. This recoil can have big implications for quantum sensing, … Read more

Scientists achieve targeted laser excitation of thorium nuclei, paving way for advanced clocks and fundamental physics studies

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Physicists have been hoping for this moment for a long time: For many years, scientists all around the world have been searching for a very specific state of thorium atomic nuclei that promises revolutionary technological applications. It could be used, for example, to build a nuclear clock that could measure time more precisely than the … Read more

Efficient generation and control of entanglement in superconducting qubit arrays demonstrated

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Entanglement is a fascinating phenomenon in the realm of quantum physics, where particles at the atomic level exhibit correlations that defy classical explanations. This unique aspect of quantum mechanics plays a pivotal role in understanding the behavior of quantum systems, particularly in the context of quantum computing. Quantum entanglement refers to the intricate correlation between … Read more

Artificial solid with switchable interactions exhibits topological effects in transport

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In principle, one shouldn’t compare apples to oranges. However, in topology, which is a branch of mathematics, one must do just that. Apples and oranges, it turns out, are said to be topologically the same since they both lack a hole—in contrast to doughnuts or coffee cups, for instance, which both have one (the handle … Read more

Quantum Mechanics: Mysteries of the Subatomic World

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Quantum mechanics is one of the most profound and revolutionary theories in modern physics, unraveling the mysteries of the subatomic world and fundamentally transforming our understanding of matter, energy, and the fundamental forces of nature. Developed in the early 20th century through the works of pioneering physicists such as Max Planck, Albert Einstein, Niels Bohr, … Read more

Quantum Entanglement: A Journey into Non-locality

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Quantum entanglement is a fascinating and perplexing phenomenon in the realm of quantum mechanics, challenging our classical intuitions about the nature of reality. It is a concept that has captured the imagination of scientists and the public alike, leading to deep philosophical discussions and groundbreaking technological advancements. This journey into non-locality takes us into the … Read more

Scientists use cold ion crystals to study chemical reactions in space

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While it may not look like it, the interstellar space between stars is far from empty. Atoms, ions, molecules, and more reside in this ethereal environment known as the Interstellar Medium (ISM). The ISM has fascinated scientists for decades, as at least 200 unique molecules form in its cold, low-pressure environment. It’s a subject that … Read more

Engineers develop ultra-compact chip for low-noise microwave generation

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In a new Nature study, Columbia Engineering researchers have built a photonic chip that is able to produce high-quality, ultra-low-noise microwave signals using only a single laser. The compact device—a chip so small, it could fit on a sharp pencil point—results in the lowest microwave noise ever observed in an integrated photonics platform. The achievement … Read more

New europium compound identified as potential candidate for quantum memory applications

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In the quest to develop quantum computers and networks, there are many components that are fundamentally different than those used today. Like a modern computer, each of these components has different constraints. However, it is currently unclear which materials can be used to construct those components for the transmission and storage of quantum information. In … Read more

Niobium qubits rise from the ashes with new design and fabrication

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For years, niobium was considered an underperformer when it came to superconducting qubits. Now, scientists supported by Q-NEXT have found a way to engineer a high-performing niobium-based qubit and take advantage of niobium’s superior qualities. When it comes to quantum technology, niobium is making a comeback. For the past 15 years, niobium has been sitting … Read more

Researchers pioneer new method for characterizing optical quantum states

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Scientists at Paderborn University have used a new method to determine the characteristics of optical quantum states. For the first time, they are using certain photon detectors—devices that can detect individual light particles—for so-called homodyne detection. The ability to characterize optical quantum states makes the method an essential tool for quantum information processing. Precise knowledge … Read more

Long-range quantum coherence observed in bismuth bromide topological insulator

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In a groundbreaking experiment, physicists have recently observed long-range quantum coherence effects stemming from Aharonov-Bohm interference in a device based on topological insulators. This landmark discovery opens a new frontier in the realm of topological quantum physics and engineering, promising transformative possibilities for future technological development and our understanding of quantum information science. Published in … Read more