The state was reached for a fraction of a second but it is a crucial stepping stone.
Category: quantum physics – Page 320
Researchers observe the wave-particle duality of two photons
Understanding the nature of quantum objects’ behaviors is the premise for a reasonable description of the quantum world. Depending on whether the interference can be produced or not, the quantum object is endowed with dual features of a wave and a particle, i.e., the so-called wave-particle duality (WPD), which are generally observed in the so-called mutually exclusive experimental arrangements in the sense of Bohr’s complementarity principle.
Theoretical physicist John Wheeler proposed the delayed-choice experiment in the 1980s, pointing out that the methods used to observe photons will ultimately determine whether their behavior is like particles or waves.
In 2011, Ionicioiu and Terno proposed a quantum version of the delayed-choice experiment, by which the photon can be forced into a superposed state of the particle and wave and exhibits continuous morphing between those two sides with changing the controlling parameter of the ancilla.
Scientists build mass-producible miniature quantum memory element
Light pulses can be stored and retrieved in the glass cell, which is filled with rubidium atoms and is only a few millimeters in size.
Light particles are particularly suited to transmitting quantum information.
Researchers at the University of Basel have built a quantum memory element based on atoms in a tiny glass cell. In the future, such quantum memories could be mass-produced on a wafer.
It is hard to imagine our lives without networks such as the internet or mobile phone networks. In the future, similar networks are planned for quantum technologies that will enable the tap-proof transmission of messages using quantum cryptography and make it possible to connect quantum computers to each other.
Like their conventional counterparts, such quantum networks require memory elements in which information can be temporarily stored and routed as needed. A team of researchers at the University of Basel led by Professor Philipp Treutlein has now developed such a memory element, which can be micro-fabricated and is, therefore, suitable for mass production. Their results were published in Physical Review Letters.
Supernova Study Shows Dark Energy May Be More Complicated Than We Thought
Finally, after more than a decade of work and studying around 1,500 Type Ia supernovas, the Dark Energy Survey has produced a new best measurement of w. We found w = −0.80 ± 0.18, so it’s somewhere between −0.62 and −0.98.
This is a very interesting result. It is close to −1, but not quite exactly there. To be the cosmological constant, or the energy of empty space, it would need to be exactly −1.
Where does this leave us? With the idea that a more complex model of dark energy may be needed, perhaps one in which this mysterious energy has changed over the life of the universe.
‘Quantum ping-pong’: Two atoms can be made to bounce a single photon back and forth with high precision
Atoms can absorb and reemit light—this is an everyday phenomenon. In most cases, however, an atom emits a light particle in all possible directions—recapturing this photon is, therefore, quite hard.
A research team from TU Wien in Vienna (Austria) has now been able to demonstrate theoretically that using a special lens, a single photon emitted by one atom can be guaranteed to be reabsorbed by a second atom. This second atom not only absorbs the photon though, but directly returns it back to the first atom. That way, the atoms pass the photon to each other with pinpoint accuracy again and again—just like in ping-pong.
Experiment could test quantum nature of large masses for the first time
An experiment outlined by a UCL (University College London)-led team of scientists from the UK and India could test whether relatively large masses have a quantum nature, resolving the question of whether quantum mechanical description works at a much larger scale than that of particles and atoms.
Quantum theory is typically seen as describing nature at the tiniest scales, and quantum effects have not been observed in a laboratory for objects more massive than about a quintillionth of a gram, or more precisely 10-20 g.
The new experiment, described in a paper published in Physical Review Letters and involving researchers at UCL, the University of Southampton, and the Bose Institute in Kolkata, India, could, in principle, test the quantumness of an object regardless of its mass or energy.
The Rise of Pico Technology
In the vast realm of scientific discovery and technological advancement, there exists a hidden frontier that holds the key to unlocking the mysteries of the universe. This frontier is Pico Technology, a domain of measurement and manipulation at the atomic and subatomic levels. The rise of Pico Technology represents a seismic shift in our understanding of precision measurement and its applications across diverse fields, from biology to quantum computing. Pico Technology, at the intersection of precision measurement and quantum effects, represents the forefront of scientific and technological progress, unveiling the remarkable capabilities of working at the picoscale, offering unprecedented precision and reactivity that are reshaping fields ranging from medicine to green energy.
Unlocking the Picoscale World
At the heart of Pico Technology lies the ability to work at the picoscale, a dimension where a picometer, often represented as 1 × 10^−12 meters, reigns supreme. The term ‘pico’ itself is derived from the Greek word ‘pikos’, meaning ‘very small’. What sets Pico Technology apart is not just its capacity to delve deeper into smaller scales, but its unique ability to harness the inherent physical, chemical, mechanical, and optical properties of materials that naturally manifest at the picoscale.
Bridging the Quantum “Reality Gap” — Unveiling the Invisible With AI
A study led by the University of Oxford has used the power of machine learning to overcome a key challenge affecting quantum devices. For the first time, the findings reveal a way to close the ‘reality gap’: the difference between predicted and observed behavior from quantum devices. The results have been published in Physical Review X.
Quantum computing could supercharge a wealth of applications, from climate modeling and financial forecasting, to drug discovery and artificial intelligence. But this will require effective ways to scale and combine individual quantum devices (also called qubits). A major barrier against this is inherent variability: where even apparently identical units exhibit different behaviors.
The cause of variability in quantum devices.
Defying Current Theories of Superconductivity — “Sudden Death” of Quantum Fluctuations Stuns Scientists
Princeton physicists have uncovered a groundbreaking quantum phase transition in superconductivity, challenging established theories and highlighting the need for new approaches to understanding quantum mechanics in solids.
Princeton physicists have discovered an abrupt change in quantum behavior while experimenting with a three-atom.
An atom is the smallest component of an element. It is made up of protons and neutrons within the nucleus, and electrons circling the nucleus.