Lifeboat Foundation

In quantum computing, the question as to what physical system and which degrees of freedom within that system may be used to encode quantum bits of information—qubits, in short—is at the heart of many research projects carried out in physics and engineering laboratories.

Superconducting qubits, spin qubits, and qubits encoded in the motion of trapped ions are already widely recognized as prime candidates for future practical applications of quantum computers; other systems need to be better understood and thus offer a stimulating ground for fundamental investigation.

Rebekka Garreis, Chuyao Tong, Wister Huang, and their colleagues in the group of Professors Klaus Ensslin and Thomas Ihn from the Department of Physics at ETH Zurich have been looking into bilayer graphene (BLG) quantum dots, known as a potential platform for spin qubits, to find out if another degree of freedom of BLG can be used to encode quantum information.

The state was reached for a fraction of a second but it is a crucial stepping stone.

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.

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.

Continue reading “Scientists build mass-producible miniature quantum memory element” »

External driving of qubits can exploit their nonlinearity to generate different forms of interqubit interactions, broadening the capabilities of the platform.

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.

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.

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.

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.