Science Daily June 7, 2021 Based on foundational theory a team of researchers in the US (Iowa State University, University of Ohio, University of Chicago) engineered an alloy with the elements bismuth and antimony at precise ranges. In this material electrons move like massless photons, a phenomenon theoretically predicted to exist. Under the influence of an external magnetic field some of the electrons generate energy, while others absorb energy, effectively turning the material into an energy pump resulting in 300% increase in its thermal conductivity. The mechanism is turned off if the magnet is taken away. This property, and the […]
Tag Archives: Quantum science
New evidence for electron’s dual nature found in a quantum spin liquid
EurekAlert May 13, 2021 In spin liquid materials, the spins are constantly changing in a tightly coordinated, entangled choreography resulting in one of the most entangled quantum states. A team of researchers in the US (Princeton University, University of Tennessee, Oak Ridge National Laboratory, Purdue University) proposed that in the quantum regime an electron may be regarded as composed of two particles, one bearing the electron’s negative charge and the other containing its spin they called it spinon. They searched for signs of the spinon in a spin liquid composed of ruthenium and chlorine atoms. The measurements demanded an extraordinarily […]
Ion beams mean a quantum leap for color-center qubits
Phys.org April 28, 2021 An international team of researchers (USA – Lawrence Berkeley National Laboratory, Finland, Singapore, Germany) has measured depth-resolved photoluminescence of nitrogen-vacancy (NV−) centers formed along the tracks of swift heavy ions (SHIs) in synthetic single crystal diamonds that had been doped with nitrogen during crystal growth. Analysis of the spectra showed that NV− centers are formed preferentially within regions where electronic stopping processes dominate and not at the end of the ion range where elastic collisions lead to the formation of vacancies and defects. Thermal annealing further increased NV yields after irradiation with SHIs preferentially in regions […]
Magnetic effect without a magnet
Nanowerk February 22, 2021 An international team of researchers (Austria, Switzerland, Canada, USA – Rice University) found Ce3Bi4Pd3 produced a giant Hall effect in the total absence of any magnetic field and showed that the strange phenomenon is due to the complicated interaction of the electrons. Specific symmetries of the atoms determine the dispersion relation, the relationship between the energy of the electrons and their momentum. This complex interaction results in phenomena that mathematically look as if there are magnetic monopoles in the material which do not exist in this form in nature. But it has the effect of a […]
Light used to detect quantum information stored in 100,000 nuclear quantum bits
Phys.org February 15, 2021 An international team of researchers (UK, France) injected a ‘needle’ of highly fragile quantum information in a ‘haystack’ of 100,000 nuclei. By using lasers to control an electron, they could use that electron to control the behavior of the haystack, making it easier to find the needle. By controlling the collective state of the 100,000 nuclei, they were able to detect the existence of the quantum information as a ‘flipped quantum bit’ at an ultra-high precision of 1.9 parts per million: enough to see a single bit flip in the cloud of nuclei. Using this technique, […]
New state of matter in one-dimensional quantum gas
Phys.org January 14, 2021 Long-lived excited states of interacting quantum systems that retain quantum correlations and evade thermalization are of great fundamental interest. A team of researchers in the US (Stanford University, City University of New York) created nonthermal states in a bosonic one-dimensional (1D) quantum gas of dysprosium by stabilizing a super-Tonks-Girardeau gas against collapse and thermalization with repulsive long-range dipolar interactions. Stiffness and energy-per-particle measurements show that the system is dynamically stable regardless of contact interaction strength. This enables us to cycle contact interactions from weakly to strongly repulsive, then strongly attractive, and finally weakly attractive. They showed […]
Breaking through the resolution barrier with quantum-limited precision
Science Daily January 5, 2021 An international team of researchers (USA – Stanford University, Canada, Czech Republic, Spain, Germany) presents a temporal-mode demultiplexing scheme that achieves the ultimate quantum precision for the simultaneous estimation of the temporal centroid, the time offset, and the relative intensities of an incoherent mixture of ultrashort pulses at the single-photon level. They experimentally resolved temporal separations 10 times smaller than the pulse duration, as well as imbalanced intensities. This represents an improvement of more than an order of magnitude over the best standard methods based on intensity detection. The findings could allow significant improvements in […]
Scrambled supersolids: Soft form of a solid discovered
Science Daily January 4, 2021 An international team of researchers (Austria, Switzerland) created supersolids using ultracold quantum gases of highly magnetic lanthanide atoms. This state of matter is solid and liquid at the same time. Due to quantum effects, a very cold gas of atoms can spontaneously develop both a crystalline order of a solid crystal and particle flow like a superfluid quantum liquid. A dipolar supersolid can be imagined as a chain of quantum droplets which communicate with each other via a superfluid background bath. They found that if the superfluid bath between the droplets is drained by control […]
Metasurface enabled quantum edge detection
Phys.org December 29, 2020 Metasurfaces consisting of engineered dielectric or metallic structures provide unique solutions to realize exotic phenomena including negative refraction, achromatic focusing, electromagnetic cloaking, and so on. The intersection of metasurface and quantum optics may lead to new opportunities but is much less explored. An international team of researchers (China, USA – UC San Diego, Columbia University, Harvard University, Austria) proposed and experimentally demonstrated that a polarization-entangled photon source can be used to switch ON or OFF the optical edge detection mode in an imaging system based on a high-efficiency dielectric metasurface. This experiment enriches both fields of […]
Researchers achieve sustained, high-fidelity quantum teleportation
Phys.org December 29, 2020 An international team of researchers (USA – Caltech, Fermi National Accelerator Laboratory, industry, Harvard University, Canada) used fiber-coupled devices, including state-of-the-art low-noise superconducting nanowire single-photon detectors and off-the-shelf optics to achieve conditional quantum teleportation of time-bin qubits at the telecommunication wavelength of 1536.5 nm. They measured teleportation fidelities that are consistent with an analytical model of their system, which includes realistic imperfections. To demonstrate the compatibility of the setup with deployed quantum networks, they teleported qubits over 22 km of single-mode fiber while transmitting qubits over an additional 22 km of fiber. Their systems, which are […]