Thermal chaos returns quantum system to its unknown past

Nanowerk  August 6, 2020 The previous work of an international team of researchers (Russia, USA – Argonne National Laboratory, University of Chicago) dealt with a predefined quantum state. The problem with having to know which state you are reversing is the need to record it. This was not really an issue for the small computer made up of two or three quantum bits, which was used in last year’s study. But scaling up the experiment ramps up the memory requirements. Each additional qubit doubles the amount of memory needed. To address this, the researchers came up with a universal algorithm […]

NIST team builds hybrid quantum system by entangling molecule with atom  May 20, 2020 Building on the their 2017 demonstration of quantum control of a molecule, a team of researchers in the US (NIST, University of Colorado) successfully entangled two energy levels of a calcium atomic ion with two different pairs of rotational states of a calcium hydride molecular ion, which is a calcium ion bonded to a hydrogen atom. The molecular qubit had a transition frequency—the speed of cycling between two rotational states—of either low energy at 13.4 kilohertz (kHz, thousands of cycles per second) or high energy at 855 billion cycles per second (gigahertz or GHz). Molecules could […]

Quantum copycat: Researchers find a new way in which bosons behave like fermions  March 27, 2020 Researchers at Pennsylvania State University observed dynamical fermionization, where the momentum distribution of a T-G (Tonks-Girardeau) gas evolves from bosonic to fermionic after its axial confinement is removed. The asymptotic momentum distribution after expansion in one dimension is the distribution of rapidities, which are the conserved quantities associated with many-body integrable systems. Their measurements agree well with T-G gas theory. They also studied momentum evolution after the trap depth is suddenly changed to a new nonzero value, and we observed the theoretically predicted bosonic-fermionic oscillations…read more. TECHNICAL ARTICLE

Turning an organic molecule into a coherent two-level quantum system  March 18, 2019 Researchers in Germany have demonstrated that an organic molecule placed into an optical microcavity behaves as a coherent two-level quantum system. This allows the observation of 99% extinction of a laser beam by a single molecule, saturation with less than 0.5 photons and non-classical generation of few-photons super-bunched light. They demonstrated that their molecule-microcavity system could interact with single photons generated by a second molecule in a distant laboratory. The research is an important step towards linear and nonlinear quantum photonic circuits based on organic platforms…read more. TECHNICAL ARTICLE 

Quantum ‘compass’ could allow navigation without relying on satellites  November 9, 2918 At extremely low temperatures, the atoms behave in a ‘quantum’ way, acting like both matter and waves. As the atoms fall, their wave properties are affected by the acceleration of the vehicle. Using an ‘optical ruler’, the accelerometer is able to measure these minute changes very accurately. Making use of this phenomenon researchers in the UK have demonstrated a transportable, standalone quantum accelerometer. The current system is designed for navigation of large vehicles, such as ships and even trains. However, the principle can also be used for fundamental science research, such as in the search for […]