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Article 
Programmable interactions and emergent geometry in an array of atom clouds
The reported network of connectivity between atomic ensembles is entirely programmable and independent of its geometrical arrangement, because of the interaction with an optical cavity.
 Avikar Periwal
 , Eric S. Cooper
 & Monika SchleierSmith

Article
 Open AccessQuantum theory based on real numbers can be experimentally falsified
A Belllike experiment that discriminates between realnumber and complexnumber multipartite quantum systems could disprove real quantum theory.
 MarcOlivier Renou
 , David Trillo
 & Miguel Navascués

Article 
Detecting spins by their fluorescence with a microwave photon counter
An ensemble of electron spins is detected by their microwave fluorescence using a superconducting single microwave photon counter, making singlespin electron spin resonance spectroscopy a possible future prospect.
 Emanuele Albertinale
 , Léo Balembois
 & Emmanuel Flurin

Article
 Open AccessDirect limits for scalar field dark matter from a gravitationalwave detector
Using a gravitationalwave detector to listen for dark matter signatures, a direct search for scalar field dark matter was conducted and new upper limits are set on the coupling constants.
 Sander M. Vermeulen
 , Philip Relton
 & Holger Wittel

Article 
Observation of Feshbach resonances between a single ion and ultracold atoms
Magnetically tunable interactions between lithium atoms and barium ions are used to demonstrate and probe Feshbach resonances between atoms and ions, which could have applications in the fields of experimental quantum simulation and fundamental physics.
 Pascal Weckesser
 , Fabian Thielemann
 & Tobias Schaetz

Article 
TimeCrystalline Eigenstate Order on a Quantum Processor
 Xiao Mi
 , Matteo Ippoliti
 & Pedram Roushan

Article
 Open AccessQuantum gas magnifier for sublatticeresolved imaging of 3D quantum systems
Existing techniques for highresolution imaging of trapped quantum gases are limited to twodimensional systems, but the approach described here works in three dimensions by magnifying the quantum gas with matter wave optics.
 Luca Asteria
 , Henrik P. Zahn
 & Christof Weitenberg

Article 
Observation of Stark manybody localization without disorder
Experiments with a trappedion quantum simulator observe Stark manybody localization, in which the quantum system evades thermalization despite having no disorder.
 W. Morong
 , F. Liu
 & C. Monroe

Article 
An optical lattice with sound
An optical lattice for trapping a Bose–Einstein condensate reported here includes photonmediated atom–atom interactions that replicate acoustic modes in real crystals.
 Yudan Guo
 , Ronen M. Kroeze
 & Benjamin L. Lev

Article 
Experimental relativistic zeroknowledge proofs
A zeroknowledge proof, which can be used to verify secret information, is reported here with security that is enforced by the laws of special relativity.
 Pouriya Alikhani
 , Nicolas Brunner
 & Hugo Zbinden

Article 
Faulttolerant control of an errorcorrected qubit
Faulttolerant circuits for the control of a logical qubit encoded in 13 trapped ion qubits through a Bacon–Shor quantum error correction code are demonstrated.
 Laird Egan
 , Dripto M. Debroy
 & Christopher Monroe

Article 
Singlephoton nonlinearity at room temperature
Nonlinearity induced by a single photon is desirable because it can drive power consumption of optical devices to their fundamental quantum limit, and is demonstrated here at room temperature.
 Anton V. Zasedatelev
 , Anton V. Baranikov
 & Pavlos G. Lagoudakis

Article 
Continuous Mott transition in semiconductor moiré superlattices
The interaction strength in moiré superlattices is tuned to drive a continuous metaltoinsulator transition at a fixed electron density.
 Tingxin Li
 , Shengwei Jiang
 & Kin Fai Mak

Article 
Tunable selfassembled Casimir microcavities and polaritons
Gold nanoflake pairs form by selfassembly in an aqueous ligand solution and offer stable and tunable microcavities by virtue of equilibrium between attractive Casimir forces and repulsive electrostatic forces.
 Battulga Munkhbat
 , Adriana Canales
 & Timur O. Shegai

Article 
Highfidelity laserfree universal control of trapped ion qubits
Laserfree universal control of two trappedion qubits using a combination of radiofrequency and microwave magnetic fields achieves some of the highest fidelities ever reported for twoqubit maximally entangled states.
 R. Srinivas
 , S. C. Burd
 & D. H. Slichter

Article 
Emergent hydrodynamics in a strongly interacting dipolar spin ensemble
A hybrid solidstate platform based on two strongly interacting dipolar species is used to study the emergence of the classical properties of a solid from its underlying microscopic quantum description.
 C. Zu
 , F. Machado
 & N. Y. Yao

Article
 Open AccessSympathetic cooling of a trapped proton mediated by an LC circuit
A single electromagnetically trapped proton is sympathetically cooled to below ambient temperature by coupling it through a superconducting LC circuit to a lasercooled cloud of Be^{+} ions stored in a spatially separated trap.
 M. Bohman
 , V. Grunhofer
 & S. Ulmer

Article 
Twodimensional supersolidity in a dipolar quantum gas
Twodimensional supersolidity is demonstrated using highly magnetic, ultracold dysprosium atoms.
 Matthew A. Norcia
 , Claudia Politi
 & Francesca Ferlaino

Article
 Open AccessEvidence for an atomic chiral superfluid with topological excitations
A globally chiral atomic superfluid is induced by timereversal symmetry breaking in an optical lattice and exhibits global angular momentum, which is expected to lead to topological excitations and the demonstration of a topological superfluid.
 XiaoQiong Wang
 , GuangQuan Luo
 & ZhiFang Xu

Article 
Quantized nonlinear Thouless pumping
Nonlinearity is shown to induce quantized topological transport via soliton motion; specifically, we demonstrate nonlinear Thouless pumping of photons in waveguide arrays with a nonuniformly occupied energy band.
 Marius Jürgensen
 , Sebabrata Mukherjee
 & Mikael C. Rechtsman

Article
 Open AccessExponential suppression of bit or phase errors with cyclic error correction
Repetition codes running many cycles of quantum error correction achieve exponential suppression of errors with increasing numbers of qubits.
 Zijun Chen
 , Kevin J. Satzinger
 & Julian Kelly

Article 
Realtime optimal quantum control of mechanical motion at room temperature
Optimal quantum control of an optically trapped nanoparticle in its ground state is demonstrated at room temperature, using Kalman filtering to track its quantum trajectory in real time.
 Lorenzo Magrini
 , Philipp Rosenzweig
 & Markus Aspelmeyer

Article 
Quantum control of a nanoparticle optically levitated in cryogenic free space
Quantum control of an optically levitated nanoparticle with a mass of just one femtogram is demonstrated in a cryogenic environment by feedbackcooling the motion of the particle to the quantum ground state.
 Felix Tebbenjohanns
 , M. Luisa Mattana
 & Lukas Novotny

Article 
Quantum phases of matter on a 256atom programmable quantum simulator
A programmable quantum simulator with 256 qubits is created using neutral atoms in twodimensional optical tweezer arrays, demonstrating a quantum phase transition and revealing new quantum phases of matter.
 Sepehr Ebadi
 , Tout T. Wang
 & Mikhail D. Lukin

Article 
Quantum simulation of 2D antiferromagnets with hundreds of Rydberg atoms
Programmable quantum simulation of twodimensional antiferromagnets is achieved with up to 196 neutral atoms, and the capability of the platform is demonstrated on square and triangular arrays.
 Pascal Scholl
 , Michael Schuler
 & Antoine Browaeys

Article 
Demonstration of a trappedion atomic clock in space
Operating in space, NASA’s Deep Space Atomic Clock, a trappedion clock, is shown to have longterm stability and drift that are an order of magnitude better than current space clocks.
 E. A. Burt
 , J. D. Prestage
 & T. A. Ely

Article 
Accurately computing the electronic properties of a quantum ring
As a blueprint for highprecision quantum simulation, an 18qubit algorithm that consists of more than 1,400 twoqubit gates is demonstrated, and reconstructs the energy eigenvalues of the simulated onedimensional wire to a precision of 1 per cent.
 C. Neill
 , T. McCourt
 & V. Smelyanskiy

Article 
Correlated charge noise and relaxation errors in superconducting qubits
Cosmicray particles and γrays striking superconducting circuits can generate qubit errors that are spatially correlated across several millimetres, hampering current errorcorrection approaches.
 C. D. Wilen
 , S. Abdullah
 & R. McDermott

Article 
Telecomheralded entanglement between multimode solidstate quantum memories
Robust heralded entanglement between two solidstate quantum memories with temporal multiplexing is realized using photons at telecommunication wavelengths.
 Dario LagoRivera
 , Samuele Grandi
 & Hugues de Riedmatten

Article 
Heralded entanglement distribution between two absorptive quantum memories
Heralded entanglement is realized between two solidstate absorptive quantum memories 3.5 metres apart and with a bandwidth of 1 gigahertz, and with a fidelity of approximately 80%.
 Xiao Liu
 , Jun Hu
 & GuangCan Guo

Article 
CMOSbased cryogenic control of silicon quantum circuits
A cryogenic CMOS control chip operating at 3 K is used to demonstrate coherent control and simple algorithms on silicon qubits operating at 20 mK.
 Xiao Xue
 , Bishnu Patra
 & Lieven M. K. Vandersypen

Article 
Transition from an atomic to a molecular Bose–Einstein condensate
A BoseEinstein condensate of molecules is produced by pairing atoms in an atomic condensate; this transition is the bosonic analog of the BardeenCooperSchrieffer superfluid to BEC crossover in Fermi gases.
 Zhendong Zhang
 , Liangchao Chen
 & Cheng Chin

Article 
Demonstration of the trappedion quantum CCD computer architecture
The quantum chargecoupled device architecture is demonstrated, with its various elements integrated into a programmable trappedion quantum computer and performing simple quantum operations with stateoftheart levels of error.
 J. M. Pino
 , J. M. Dreiling
 & B. Neyenhuis

Article
 Open AccessNondestructive detection of photonic qubits
A nondestructive detector of photonic qubits, comprising a single ^{87}Rb atom trapped in the centre point of two crossed fibrebased optical resonators, is demonstrated.
 Dominik Niemietz
 , Pau Farrera
 & Gerhard Rempe

Article 
Control and readout of a superconducting qubit using a photonic link
Highfidelity control and readout of a superconducting qubit is performed with a lownoise optical fibre link that delivers microwave signals directly to the millikelvin quantum computing environment.
 F. Lecocq
 , F. Quinlan
 & J. D. Teufel

Article 
A fourqubit germanium quantum processor
Using germanium quantum dots, a fourqubit processor capable of single, two, three, and fourqubit gates, demonstrated by the creation of fourqubit Greenberger−Horne−Zeilinger states, is the largest yet realized with solidstate electron spins.
 Nico W. Hendrickx
 , William I. L. Lawrie
 & Menno Veldhorst

Article 
Experimental quantum speedup in reinforcement learning agents
A reinforcement learning experiment using a programmable integrated nanophotonic processor shows that a quantum communication channel with the environment speeds up the learning process of an agent.
 V. Saggio
 , B. E. Asenbeck
 & P. Walther

Article 
Quantum circuits with many photons on a programmable nanophotonic chip
A system for realizing manyphoton quantum circuits is presented, comprising a programmable nanophotonic chip operating at room temperature, interfaced with a fully automated control system.
 J. M. Arrazola
 , V. Bergholm
 & Y. Zhang

Article 
Deterministic multiqubit entanglement in a quantum network
Highfidelity deterministic quantum state transfer and multiqubit entanglement are demonstrated in a quantum network comprising two superconducting quantum nodes one metre apart, with each node including three interconnected qubits.
 Youpeng Zhong
 , HungShen Chang
 & Andrew N. Cleland

Article
 Open AccessCoherent Xray−optical control of nuclear excitons
Suitably shaped Xray pulses are used to coherently steer the quantum dynamics of atoms’ nuclei rather than their electrons, with fewzeptosecond temporal stability of the phase control.
 Kilian P. Heeg
 , Andreas Kaldun
 & Jörg Evers

Article 
Protecting a bosonic qubit with autonomous quantum error correction
A logical qubit encoded in multiphoton states of a superconducting cavity is protected with autonomous correction of certain quantum errors by tailoring the dissipation it is exposed to.
 Jeffrey M. Gertler
 , Brian Baker
 & Chen Wang

Article 
A quantum enhanced search for dark matter axions
A quantum enhanced search for dark matter that uses vacuum squeezing to overcome the quantum noise limit finds no evidence of dark matter axions in a well motivated mass range.
 K. M. Backes
 , D. A. Palken
 & H. Wang

Article 
Entangling logical qubits with lattice surgery
Two logical qubits are encoded in ensembles of four physical qubits through the surface code, then entangled by lattice surgery, which is a protocol for carrying out faulttolerant operations.
 Alexander Erhard
 , Hendrik Poulsen Nautrup
 & Thomas Monz

Article 
Competing magnetic orders in a bilayer Hubbard model with ultracold atoms
A bilayer Fermi–Hubbard model is realized in two coupled twodimensional layers of fermionic ultracold atoms by tuning the interlayer coupling strength to create a crossover between magnetic orderings.
 Marcell Gall
 , Nicola Wurz
 & Michael Köhl

Article 
An integrated spacetoground quantum communication network over 4,600 kilometres
A quantum network that combines 700 fibre and two groundtosatellite links achieves quantum key distribution between more than 150 users over a combined distance of 4,600 kilometres.
 YuAo Chen
 , Qiang Zhang
 & JianWei Pan

Article 
Superconducting qubit to optical photon transduction
A chipscale platform is developed for the conversion of a single microwave excitation of a superconducting qubit into optical photons, with potential uses in quantum computer networks.
 Mohammad Mirhosseini
 , Alp Sipahigil
 & Oskar Painter

Article 
Entanglement on an optical atomicclock transition
A manyatom state of trapped ^{171}Yb atoms that are entangled on an optical atomicclock transition overcomes the standard quantum limit, providing a proofofprinciple demonstration towards entanglementbased optical atomic clocks.
 Edwin PedrozoPeñafiel
 , Simone Colombo
 & Vladan Vuletić

Article 
Halfminutescale atomic coherence and high relative stability in a tweezer clock
A tweezer clock containing about 150 ^{88}Sr atoms achieves trapping and optical excitedstate lifetimes exceeding 40 seconds, and shows relative fractional frequency stability similar to that of leading atomic clocks.
 Aaron W. Young
 , William J. Eckner
 & Adam M. Kaufman

Article 
Spin transport in a tunable Heisenberg model realized with ultracold atoms
Spin transport far from equilibrium is studied in a Heisenberg model with adjustable anisotropy realized with coupled ultracold ^{7}Li atoms, and different dynamical regimes are found for positive and negative anisotropies.
 Paul Niklas Jepsen
 , Jesse AmatoGrill
 & Wolfgang Ketterle