All articles starting with R
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Rybinsk
Rybinsk (Рыбинск), formerly Shcherbakov and Andropov, is a city in Yaroslavl Oblast, Russia, on the Volga at the Rybinsk Reservoir; first mentioned in 1071, a city since 1777, population about 169,600, an engine-building and shipbuilding center.
Rybnik
Rybnik is a city with powiat rights in Poland's Silesian Voivodeship, 126,248 inhabitants, 148.36 km², 27 districts. Former coal-mining hub once called Poland's smog capital, now a clean-air and energy-transition example.
Rybnik power station
Rybnik power station, or Elektrownia Rybnik, is a hard-coal-fired power plant in Rybnik, southern Poland, owned by PGE and generating electricity and district heat since 1972.
Rydal Mount
Rydal Mount is a Grade I listed house in Rydal, Cumbria, home of poet William Wordsworth from 1813 until his death in 1850, with a terraced 5-acre garden he designed; acquired by the Wordsworth Trust in March 2026.
Rydberg atom
A Rydberg atom is an atom with one or more electrons excited to a very high principal quantum number, making it useful for electric-field sensing and quantum computing.
Rydberg atom array
A Rydberg atom array is a quantum computing platform in which neutral atoms are trapped in optical tweezers and made to interact through Rydberg states.
Rydberg atom quantum sensor
A Rydberg atom quantum sensor measures radio-frequency and microwave electric fields using alkali atoms in a vapor cell, read out optically by lasers rather than antennas.
Rydberg atom quantum simulator
A Rydberg atom quantum simulator is a programmable device in which neutral atoms trapped in optical tweezer arrays simulate quantum spin models, with experiments controlling more than 100 qubits.
Rydberg atom radio-frequency receiver
A Rydberg atom radio-frequency receiver is a quantum sensor that converts radio and microwave signals into changes in laser light passing through a vapor of Rydberg atoms.
Rydberg blockade
The Rydberg blockade is a quantum-optical effect where the strong interaction between atoms in high-lying Rydberg states prevents simultaneous excitation of nearby atoms, enabling entangling gates in neutral-atom quantum computing.
Rydberg blockade gate
A Rydberg blockade gate is a two-qubit entangling quantum logic gate between neutral atoms, in which strong atom-atom interaction blocks simultaneous Rydberg excitation, producing a controlled phase.
Rydberg blockade quantum gates
A Rydberg blockade quantum gate is a two-qubit entangling gate for neutral atoms in which the Rydberg interaction lets only one neighboring atom be excited at a time.
Rydberg constant
The Rydberg constant, symbol R∞, also called the Rydberg wavenumber, is a physical constant setting the scale of hydrogen-like atoms' spectral lines; its value is known to about one part in a trillion.
Rydberg crystal
A Rydberg crystal is a spatially ordered arrangement of Rydberg excitations in an ultracold gas, first imaged in 2012 with excitations forming triangles, squares, and pentagons.
Rydberg dressing
Rydberg dressing is a technique in atomic physics in which a weak off-resonant laser admixes a small Rydberg-state fraction into ground-state atoms, giving tunable long-range interactions.
Rydberg exciton
A Rydberg exciton is a bound electron–hole pair in a semiconductor in a highly excited state, the condensed-matter counterpart of the Rydberg atom, studied chiefly in cuprous oxide.
Rydberg exciton polaritons
Rydberg exciton polaritons are hybrid light-matter quasiparticles formed when cavity photons strongly couple to Rydberg excitons, the highly excited bound electron-hole states of a semiconductor, giving few-photon optical nonlinearities in a solid-state platform.
Rydberg excitons in cuprous oxide
Rydberg excitons in cuprous oxide are giant electron-hole bound states in the semiconductor Cu2O, where excitons were discovered in 1952 and states reach quantum number 25.
Rydberg facilitation
Rydberg facilitation, also called Rydberg antiblockade, is an effect in laser-driven ultracold atoms where one Rydberg excitation brings a neighbor into resonance, enabling entangling gates and quantum sensing.
Rydberg formula
The Rydberg formula, also called the Rydberg equation, is an empirical formula giving the wavenumbers of hydrogen's spectral lines as term differences; Rydberg published it in 1890.
Rydberg macrodimer
A Rydberg macrodimer is a giant molecule of two highly excited Rydberg atoms bound by long-range electrostatic forces, with micrometer bond lengths and megahertz-scale binding energies.
Rydberg polariton
A Rydberg polariton is a quasiparticle mixing a photon with an atomic Rydberg excitation, formed in cold atoms under electromagnetically induced transparency and giving photons strong mutual interactions.
Rydberg polaritons
Rydberg polaritons are hybrid light–matter quasiparticles in which photons are dressed by highly excited Rydberg states, giving photons strong interactions used for single-photon switching and quantum gates.
Rydberg polaron
A Rydberg polaron is a quasiparticle formed when a highly excited Ryd atom binds many ground-state atoms in an ultracold gas, first observed in 2018.
Rydberg quantum simulator
A Rydberg quantum simulator is a quantum simulator built from neutral atoms in optical tweezers, where laser excitation to Rydberg states provides strong, tunable interactions for simulating many-body quantum systems.
Rydberg series
A Rydberg series is a sequence of spectral lines or energy levels converging to an ionization limit, described by the Rydberg formula with a quantum defect.
Rydberg single-photon switch
A Rydberg single-photon switch is an optical device where one stored gate photon blocks the transmission of a later light pulse in an ultracold atomic medium.
Rydberg state
A Rydberg state is a highly excited state of an atom, molecule, or exciton, where an electron occupies a high-n orbital, giving huge size and strong electric-field sensitivity.
Rydberg-dressed gates
A Rydberg-dressed gate is an entangling gate for neutral-atom qubits in which off-resonant coupling of ground states to a Rydberg state yields a distance-independent soft-core interaction, demonstrated in a 2021 controlled-phase gate.
Rydel Lynch
Rydel Lynch (Rydel Mary Lynch, born 1993) is an American singer and keyboardist, the only female member of the family pop band R5 formed with her brothers.