To date, when physicists have dreamed of quantum computing devices, they have most often envisioned encoding the data in terms of
electron spin states.
The U.S. Department of Energy's Ames Laboratory has discovered and described the existence of a unique disordered
electron spin state in a metal that may provide a unique pathway to finding and studying frustrated magnets.
Not exact matches
Each hydrogen atom, made up of just a single proton and
electron, can be found in two slightly different
states: a higher energy
state in which the
electron and proton essentially
spin in the same direction, and a lower energy
state in which they
spin in opposite directions.
This chip utilizes specific wavelengths of infrared light to stabilize the vibration
state of «
spinning»
electrons.»
(Photons, like
electrons, can exist in only one of two
states; polarization, in this case, functions just like
spin as far as Bell - type correlations are concerned.)
For half a century, the Mermin - Wagner theorem has addressed this question by
stating that if 2 - D materials lack magnetic anisotropy, a directional alignment of
electron spins in the material, there may be no magnetic order.
One sent these
electrons into a fuzzy quantum
state, in which the
spin of each
electron had a 50 - 50 chance of being either up or down.
«But when the laser hits the
electron in a quantum system, it creates many possible
spin states, and that greater range of possibilities forms the basis for more complex computing.»
By understanding and using the different
states achieved when an
electron's
spin rotates, researchers could potentially increase information storage capacity in computers, for example.
You and Bob also share a pair of
electrons — you have one, Bob has the other — and they're in an entangled
state such that if yours is
spinning up, his is
spinning down, and conversely.
Spintronics refers to technologies used in solid -
state devices that take advantage of the inherent
spin in
electrons and their related magnetic momentum.
Electrons can be thought of as having two distinct
spin states, «up» or «down.»
In the strange world of quantum physics, an
electron can also be represented as a wavefunction that encodes information about the particle, such as the probability of finding it in a particular
spin state.
Today, this behaviour is very well understood at the microscopic level: magnetism goes back to the angular momentum — the
spin — of the
electrons in the outer shell of the atoms that build up a solid
state crystal.
This bound
spin - direction
state is like our
electron's bicycle, keeping it rolling along powerfully enough to overcome bumps in the one - dimensional road.»
But because
electron spins offer one of the most promising models for quantum bitsphysical
states that can store far more information than conventional computer bitsscientists have sought ways around the coherence problem.
Now, the same researchers have found a set of materials which encourage the pairing of
spin - aligned
electrons, so that a
spin current flows more effectively in the superconducting
state than in the non-superconducting (normal)
state.
but the
states are correlated so that if Alice measures her particle from the pair and finds it
spinning, say, up, she'll know instantly that Bob's
electron is
spinning down.
UCSB's David Awschalom and his longtime collaborator at Penn
State, Nitin Samarth, devised a new technique for manipulating
electron spins within ultrafast timescales.
QSLs are strange
states achieved in solid materials where the magnetic moments, or «
spins,» associated with
electrons exhibit a fluidlike behavior.
But thanks to an eerie quantum effect known as superposition — which allows an atom,
electron or other particle to exist in two or more
states, such as «
spinning» in opposite directions at once — a single qubit made of a particle in superposition can simultaneously encompass both digits.
Now researchers at the University of Utah, The Florida
State University, University College London and the University of Sydney in Australia report a way to extend that informational lifetime to more than 100 seconds by encoding an
electron's
spin onto the much longer - lived
spin of an atomic nucleus, which can then be read out electronically.
The left diagram depicts the
spin - blockaded biexciton
state that relaxes into a dark exciton and produces a photon; solid circles are
electrons while empty ones are holes.
The researchers used a technique called inelastic
electron tunneling spectroscopy to probe the quantum
spin states of a single cobalt atom bound to an MgO layer.
Researchers from North Carolina
State University have discovered that
electron spin brings a previously unknown degree of order to the high entropy alloy nickel iron chromium cobalt (NiFeCrCo)-- and may play a role in giving the alloy its desirable properties.
Stacking up two «atomic sandwiches» yields coupled excited charge
states across the planar interface with the magnetic direction or «
spin state» becoming aligned for a large population of
electrons.
He adds that the very difficult next step would be to find a way to bind together the
spin states of multiple
electrons within these wells.
Controlling the
electron spins without destroying the coherent quantum
states has proven difficult with other techniques, but a series of experiments by the group has shown the quantum
states remain solid.
Electrons and nuclei can act like tiny bar magnets with a
spin that is assigned a directional
state of either «up» or «down.»
That's because in the excited
state, two
electrons waltz through the molecule,
spinning like tops, and only when the
electron spins point in opposite directions does the dance end with the release of a photon.
In this approach, a qubit» 0»
state is defined when the
spin of the
electron is down and the nucleus
spin is up, while the» 1»
state is when the
electron spin is up, and the nuclear
spin is down.
In these images, the initial
spin - singlet exciton
state (left), which features
electron - hole pairs, splits into a pair of
spin - triplet excitons (right).
Although a
spin - liquid
state has previously been observed in herbertsmithite, there has never been a detailed analysis of how the material's
electrons respond to light — a key to determining which of several competing theories about the material is correct.
Rey says that the strontium atoms in the ground
state can be used to simulate
spin - down
electrons, and the excited atoms,
spin - up
electrons.
Identification of deep - gap
states in a-Si: H by photodepopulation - induced
electron -
spin resonance
Credit: Doug Irving and James LeBeau, North Carolina
State University Researchers from North Carolina
State University have discovered that
electron spin brings a previously... in giving the alloy its desirable properties.
Here, we propose a dissipative scheme that achieves the preparation of pairs of nuclear
spins in long - lived singlet
states by a protocol that combines the interaction between the nuclei and a periodically reset
electron spin of a nirogen - vacancy center with local radio - frequency control of the nuclear
spins.
Spectroscopy - Energy
states of real diatomic molecules: For any real molecule, absolute separation of the different motions is seldom encountered since Another dating method using
electron spin resonance (ESR)-- also known as
electron paramagnetic resonance (EPR)-- is based on the measurement of