A series of trapped calcium ions was used to simulate the complex dynamics an interacting spin system.

We experimentally demonstrate a quantum walk on line in phase space using one and two trapped ion. A with up to 23 steps is realized by subjecting an ion state-dependent displacement operations interleaved coin tossing operations. To analyze the ion's motional state after each step we apply technique that directly maps probability density distribution onto internal state. The measured distributions position's second moment clearly show non-classical character of walk. further highlight...

Hybrid systems of laser-cooled trapped ions and ultracold atoms combined in a single experimental setup have recently emerged as new platform for fundamental research quantum physics. This paper reviews the theoretical progress on cold hybrid ion-atom which aim to combine best features two well-established fields. We provide broad overview description mixtures their applications, report advances experiments with Paul or dipole traps overlapped cloud atoms, directly produced Bose-Einstein...

We report on quantum simulations of relativistic scattering dynamics using trapped ions. The simulated state a particle is encoded in both the electronic and vibrational an ion, representing discrete continuous components wave functions. Multiple laser fields auxiliary ion simulate generated by Dirac equation presence potential. Measurement reconstruction packet enables frame-by-frame visualization processes. By precisely engineering range external potentials we are able to text book...

We propose and theoretically investigate a hybrid system composed of crystal trapped ions coupled to cloud ultracold fermions. The form periodic lattice induce band structure in the atoms. This combines advantages scalability tunability atomic systems with high fidelity operations detection offered by ion systems. It also features close analogies natural solid-state systems, as degrees freedom couple phonons lattice, thereby emulating system. Starting from microscopic many-body Hamiltonian,...

We give a detailed description of the implementation Mølmer–Sørensen gate entangling two 40Ca+ ions using bichromatic laser beam near-resonant with quadrupole transition. By amplitude pulse shaping and compensation ac-Stark shifts we achieve fast operation without compromising error rate. Subjecting different input states to concatenations up 21 individual operations reveals Bell state fidelities above 0.80. In principle, does not require ground cooling as long Lamb–Dicke criterion is...

Arrays of trapped atoms are the ideal starting points for developing registers comprising large numbers physical qubits storing and processing quantum information. One very promising approach involves neutral atom traps produced on microfabricated devices known as chips, almost arbitrary trap configurations can be realized in a robust compact package. Until now, however, chip experiments have focused small systems incorporating single or only few individual traps. Here, we report...

We propose the quantum simulation of a fermion and an antifermion field modes interacting via bosonic mode, present possible implementation with two trapped ions. This platform allows for scalable add-up fermionic modes, represents avenue towards simulations theories in perturbative nonperturbative regimes.

A basic assumption behind the inequalities used for testing noncontextual hidden variable models is that observables measured on same individual system are perfectly compatible. However, compatibility not perfect in actual experiments using sequential measurements. We discuss resulting "compatibility loophole" and present several methods to rule out certain which obey a kind of extended noncontextuality. Finally, we detailed analysis experimental imperfections recent trapped ion experiment...

The family of $n$-bit Toffoli gates, with the two-bit gate as figurehead, are great interest in quantum information they can be used universal gates and error correction, among other things. We present a single-step implementation arbitrary (up to local change basis), based on resonantly driving single qubit that has strong Ising coupling $n$ qubits. setup two-qubit case turns out identical Barenco gate. time are, theory, independent number control qubits, scaling better than conventional...

We propose the quantum simulation of Dirac equation with potentials, allowing study relativistic scaterring and Klein tunneling. This effect permits a positive-energy particle to propagate through repulsive potential via population transfer negative-energy components. show how engineer scalar, pseudoscalar, other potentials in 1+1 by manipulating two trapped ions. The spinor is represented internal states one ion, while its position momentum are described those collective motional mode....

A quantum simulator is a device engineered to reproduce the properties of an ideal model. It allows study systems that cannot be efficiently simulated on classical computers. While universal computer also simulator, only particular have been up now. Still, there wealth successful cases, such as spin models, chemistry, relativistic physics and phase transitions. Here, we show how design for Majorana equation, non-Hamiltonian wave equation might describe neutrinos other exotic particles beyond...

We consider the quantum simulation of relativistic mechanics, as described by Dirac equation and classical potentials, in trapped-ion systems. concentrate on three problems growing complexity. Firstly, we study bidimensional scattering single particles a linear potential. Secondly, explore case particle magnetic field its topological properties. Finally, analyze problem two that are coupled controllable confining The latter interaction may be useful to important phenomena such confinement...

We report on the observation of cold collisions between $^6$Li atoms and Yb$^+$ ions. This combination species has recently been proposed as most suitable for reaching quantum limit in hybrid atom-ion systems, due to its large mass ratio. For ions prepared $^2S_{1/2}$ ground state, charge transfer association rate is found be at least~10$^{3}$ times smaller than Langevin collision rate. These results confirm excellent prospects $^6$Li--Yb$^+$ sympathetic cooling information applications....

We theoretically investigate trapped ions interacting with atoms that are coupled to Rydberg states. The strong polarizabilities of the levels increases interaction strength between and by many orders magnitude, as compared case ground state atoms, may be mediated over micrometers. calculate such interactions can used generate entanglement an atom motion or internal ion. Furthermore, ion could a bus for mediating spin-spin atomic spins in analogy much employed techniques trap quantum...

We measure chemical reactions between a single trapped $^{174}$Yb$^+$ ion immersed in an ultracold bath of $^6$Li atoms containing trace amounts Li$_2$ dimers. This produces LiYb$^+$ molecular ions that we detect via mass spectrometry. explain the reaction rates by modelling dimer density as function magnetic field and obtain excellent agreement when assume to follow Langevin rate. Our results present novel approach towards creation cold point exploration chemistry molecule collisions. What...

We consider the quantum simulation of quadratic spin-phonon coupling in a crystal trapped ions. The is implemented using tightly focused optical tweezers on each ion that change local trapping potential state-dependent way. By encoding spins internal states ions and adding tunneling term via M{\o}lmer-S{\o}rensen-type interactions, we calculate emergence mobile bipolarons driven by zero-point energy phonons. show thermal occupation may pin for crystals at finite temperature. Our scheme can...

We theoretically investigate the properties of a double-well bosonic Josephson junction coupled to single trapped ion. find that coupling between wells can be controlled by internal state ion, which used for studying mesoscopic entanglement two systems and measure their interaction with high precision. As particular example we consider $^{87}\mathrm{Rb}$ atom small Bose-Einstein condensate $^{171}\mathrm{Yb}^{+}$ calculate interwell rates reaching hundreds Hz, while dependence amounts tens...

We demonstrate excitation of a single trapped cold ${^{40}\mathrm{Ca}}^{+}$ ion to Rydberg levels by laser radiation in the vacuum ultraviolet at wavelength 122 nm. Observed resonances are identified as $3d{^{2}D}_{3/2}$ $51F$, $52F$ and $3d{^{2}D}_{5/2}$ $64F$. model line shape our results imply large state-dependent coupling trapping potential. ions great interest for future applications quantum computing simulation, which dipolar interactions combined with superb experimental control...

We report on the observation of interactions between ultracold Rydberg atoms and ions in a Paul trap. The rate observed inelastic collisions, which manifest themselves as charge transfer ions, exceeds that Langevin collisions for ground state by about 3 orders magnitude. This indicates huge increase interaction strength. study effect vacant trap's electric fields excitation spectra. To quantitatively describe exhibited shape ion loss spectra, we need to include ion-induced Stark shift atoms....

We have realized a two-dimensional permanent magnetic lattice of Ioffe-Pritchard microtraps for ultracold atoms. The is formed by single $300\text{\ensuremath{-}}\mathrm{nm}$ magnetized layer FePt, patterned using optical lithography. Our consists more than 15 000 tightly confining with density $1250\phantom{\rule{0.3em}{0ex}}\text{traps}∕{\mathrm{mm}}^{2}$. Simple analytical approximations the fields produced are used to derive relevant trap parameters. load atoms into at least 30 sites...