The Early Career Conference in Trapped Ions aims to give PhD students and early career researchers the opportunity to present their work to a supportive international audience. The conference should be of interest to researchers in quantum information and technology, quantum optics, precision frequency measurements, atomic clocks, antimatter and quantum simulation. Attendees will have the...
Optical atomic clocks are amongst the most sensitive instruments ever to have been created. Although their only output is a stable frequency, their intense precision allows them to probe tiny effects at the edge of our understanding of physics. These devices measure the energy difference between two atomic energy levels by relating it to the frequency of light. In doing so, they create...
The BASE collaboration, situated at CERN's Antiproton Decelerator facility, uses Penning traps to test the Charge-Parity-Time (CPT) symmetry by measuring the fundamental properties of protons and antiprotons to ultra-high precision [1].
One such property which can be directly measured in Penning traps is the proton-to-antiproton charge-to-mass ratio,...
Simple atomic systems are the ideal probe to test fundamental physics. For example, for hydrogen the 1S-2S transition frequency can nowadays be calculated with an impressive relative accuracy of 10$^{-12}$ [1], and measurements reach an even higher relative accuracy of 10$^{-15}$[2]. Combining different measurements in hydrogen has been used to determine fundamental constants such as the...
Precision spectroscopy of molecules promises a wealth of interesting applications e.g. for better determination of natural constants, for tests of fundamental particle theories, and for qubit realizations. Unfortunately, most molecules do not possess closed transitions for laser cooling, crucial for obtaining temperatures low enough for exploiting this novel realm of physics.
A way to...
Forbidden optical transitions in highly charged ions (HCI) are the most sensitive systems for probing the variation of the fine structure constant α [1]. Moreover, they have been proposed as novel frequency standards due to their low polarizability and insensitivity to black body radiation [2]. HCI are typically produced in an electron beam ion trap (EBIT) with MK temperatures, which restricts...
Optical clocks are the most accurate time keeping instruments to date. However, widespread use is being prevented by their large size, high cost and high technical complexity of operation. To overcome these hindrances we are developing a compact, turn-key-operation portable optical clock based on trapped single Ca$^\textrm{+}$ ions. The system fits in a 4 unit 19 inch module box (500x520x160...
Trapped Rydberg ions are a novel approach for quantum information processing [1]. By combining the high degree of control of trapped ion systems with the long-range dipolar interactions of Rydberg atoms [2], fast entanglement gates may be realized in large ion crystals [1,3].
Quantum information processing in such a system uses low-lying electronic states for storage of qubits and strongly...
With solely visible and near-infrared wavelength fine-structure transitions, and isotopes with diverse nuclear spins, Barium makes an ideal candidate for developing novel quantum computing architectures. I will present our designs for a versatile and open-access quantum computer which leverages these favorable features of Barium. The visible and near-infrared wavelengths allows for the use of...
While three-dimensional sub-Doppler cooling of ions in a Paul trap has become routine, such cooling is harder to realise in a Penning trap. We have recently demonstrated optical sideband cooling of a single ion as well as the axial and planar configurations of a 2 ion crystal [1,2]. We will present preliminary results of the creation of a superposition of motional states to investigate...
Quantum networks promise the ultimate in secure connectivity providing channels of communication that are both tamper proof and tamper evident. A quantum network can be executed by remotely linking distance memory nodes comprising trapped-ion qubits via photon-based qubit interconnects. AFRL is pursuing a multi-pronged approach to develop in-house quantum networking capabilities that...
The trapped-ion quantum computer platform benefits from long coherence times [1] and high gate fidelities [2]. Due to the spectral density of motional modes, co-trapping and mutually controlling a large number of ionic qubits in a single trap is technically challenging. Therefore, large-scale trapped-ion quantum computers will require interfaces connecting many individual traps [3-5]. We...
We have performed Doppler-free two-photon spectroscopy of cold, trapped HD$^+$ ions to measure a ro-vibrational transition frequency with a relative uncertainty of a few parts-per-trillion. Using highly precise ab-initio calculations [1], these measurements allow – for the first time – to determine the proton-electron mass ratio, $\mu$, from molecular spectroscopy with a precision...
Collinear laser spectroscopy (CLS) is a powerful tool to access nuclear ground state properties of short-lived radionuclides by measuring the atomic or ionic hyperfine structure [1,2]. This technique uses fast (~30 keV) beams to minimize the Doppler broadening and thus, approaching the natural linewidth which is necessary to resolve the hyperfine structure. However, in order to explore the...
Atomic mass measurements are vital to improve our understanding of the nuclear structure, astrophysical reaction paths, and test predictions of physics beyond Standard model. The measurement Penning trap at TRIUMF’s Ion Trap for Atomic and Nuclear science (TITAN) facility is dedicated to performing high-precision mass measurements of short-lived radioactive isotopes. With the availability of...
Antihydrogen is an exciting tool for testing fundamental physics. Antihydrogen can reproducibly be synthesized and trapped in the laboratory for extended periods of time [1][2], offering an opportunity to study its properties with high precision. Of particular interest is the two-photon 1S-2S transition, due to the staggering precision of which it has been measured in hydrogen [3]. Since only...
The observed baryon asymmetry in our universe challenges the Standard Model of particle physics and motivates sensitive tests of CPT invariance. Inspired by this, the BASE experiment at CERN compares the fundamental properties of antiprotons and protons with high precision using an ultra-low noise cryogenic multi-Penning trap apparatus.
One particular challenge is imposed by electric-field...
We, the BASE collaboration, perform most precise tests of the CPT symmetry in the baryon sector by measurements of the fundamental properties of protons and antiprotons. Our recent 300 ppt measurement of the proton magnetic moment at the proton g-factor experiment in Mainz is predominantly limited by statistics [1]. The reason is that the current use of sub-thermal cooling of a single proton...
The ALPHA colaboration has recently demonstrated laser and microwave spectroscopy of several
different transitions in the antihydrogen atom. Since we typically trap around only twenty
antihydrogen atoms per experimental cycle, in these experiments we choose to accumulate hundreds
of antihydrogen atoms over time scales ranging from tens of minutes to many hours in order to have
a sufficient...
Trapped ions are a promising platform for quantum information processing. However, it is difficult to scale up the number of qubits in a single trap. One potential scaling approach lies in building multiple traps and entangling ions from different traps through quantum channels. Such entanglement mediated by photons has been demonstrated experimentally. In this scheme, the polarization of each...
Trapped ion qubits achieve excellent coherence times and gate fidelities, well below the threshold for fault tolerant quantum error correction. A key challenge now is to scale ion quantum processors to the large number of qubits required for error-corrected algorithms to run. We present progress on the implementation of high fidelity ion qubits in a modular architecture designed for true...
Quantum computers need to fulfill five criteria as stated by DiVincenzo [1]. Trapped-ion quantum computers excel in all but one criterion: scalability remains hindered by challenges on system- and device-level. To that end, the quantum CCD architecture (QCCD) [2,3] has been introduced for scalable quantum computation and simulation. As a first step in this direction we demonstrate the...
We present progress towards improved microwave driven quantum logic gate speeds and fidelities in a next-generation surface-electrode ion-trap.
Trapped ions are a leading candidate for building a general-purpose quantum computer [1]. As spontaneous emission is an incoherent process, good candidate qubits for such a device are separated by a dipole forbidden transition. Common choices are...
Entangling operations are a necessary tool for large-scale quantum information processing, but experimental imperfections can prevent current schemes from reaching sufficient fidelities as the number of qubits is increased. Previous theoretical and experimental work has considered classes of errors including static offsets in the motional frequency, heating of the bus mode and timing errors...
A Penning mass spectrometry technique based on optical detection is under development in the University of Granada [1]. This technique is universal, non-destructive, and single ion-sensitive. The scattered photons by a $^{40}$Ca$^{+}$ ion will be used to measure the normal mode eigenfrequencies of the unbalanced crystal formed by this ion and the target one [2]. The dynamics of the two-ion...
Our project is aimed at using a laser-cooled trapped ion cloud as a detector for very heavy molecules. The basic principle is to propel a heavy molecular ion with a low charge through an ion cloud while monitoring the fluorescence of the latter. Current techniques have many disadvantages we propose to overcome. While current detection techniques for giant molecules are limited to relatively...
The trapping of charged particles by radiofrequency (RF) electric fields has proven to be both a powerful and versatile tool for experimental exploration in physics and chemistry and linear ion trap happen to be candidate of choice for the design of micro-wave atomic clock for spacecraft navigation [1]. The main factor limiting the stability of such clocks is the second order Doppler effect...
Throughout its existence, the Standard Model has proven very successful in describing fundamental interactions of elementary particles. However, one observation, which has yet to be understood, is the asymmetry between the abundance of matter and antimatter in the universe. The BASE experiment, located at CERN’s Antiproton Decelerator (AD) facility, measures the fundamental properties of...
C$_2^-$ and other anionic molecules are produced with an electric discharge valve and accelerated to 1.8 keV in a pulsed electric field. The C$_2^-$ are then mass selected in a Wien filter. Subsequently the C$_2^-$ are decelerated in the static electric field of a resistive tube with a potential difference of 1.798 kV to reduce the energy of the particles to a trappable range. A digital RF...
The aim of the GBAR experiment is to measure the effect of gravity on antihydrogen atoms [1]. Those are created by interactions of antiprotons with a dense positronium cloud. The antiprotons are obtained from the decelerator complex at CERN now composed of two steps: the Antiproton Decelerator, in which the beam reaches 5 MeV energy, and ELENA where it is further decelerated to 100 keV....
David Bretaud
Bogdan Okhrimenko
Adrien Poindron
Samuel Niang
Jacopo Mosca Toba
Joseph Goodwin
David Bretaud
Stefan Erlewein
Markus Wiesinger
Peter Granum
April Louise Cridland
Hiroto Fujisaki
Peter Drmota
Michal Hejduk
Billy Robertson
Ryan Shaffer
Alexandra Tofful
Vera Schäfer
Alex Owens
Julian Schmidt
Charles Baynham
H Evans
Bianca Veglia
Elmer Grundeman
Matthias Germann
Ivan Kosternoy
Bruno Ximenez
Nicolas Pulido Mateo
Sam Hile
Matthew Day
Elia Perego
Fabian...
Marylise Marchenay
André Kulosa
Roshani Silwal
Sam Hile
Laura Blackburn
Silke Auchter
David Bretaud
Hiroto Fujisaki
Michal Hejduk
Billy Robertson
Ryan Shaffer
Alexandra Tofful
Vera Schäfer
Alex Owens
Julian Schmidt
Charles Baynham
André Kulosa
Bogdan Okhrimenko
H Evans
Marylise Marchenay
Elmer Grundeman
Matthias Germann
Roshani Silwal
Laura Blackburn
Silke Auchter
Adrien Poindron
Jacopo Mosca Toba
Joseph Goodwin
Elia Perego
Emilie Hindbo Clausen
Shaobo Gao
Tatiana Vovk
Janko Nauta
Joaquín Berrocal Sánchez
Jonathan Pinder
Alberto Uribe
Markus Wiesinger
Christian Zimmer
Peter Drmota
H Evans
Bianca Veglia
Ivan Kosternoy
Simon Lechner
Nicolas Pulido Mateo
Sam Hile
Bruno Ximenez
Chiara Decaroli
Mitchell Peaks
Simon Clark
Chris Whitty
Peter Granum
Hiroto Fujisaki
Michal Hejduk
Billy Robertson
Ryan Shaffer
Alexandra Tofful
David Bretaud
Stefan Erlewein
Markus Wiesinger
Peter Granum
April Louise Cridland
Hiroto Fujisaki
Peter Drmota
Michal Hejduk
Billy Robertson
Ryan Shaffer
Alexandra Tofful
Vera Schäfer
Alex Owens
Julian Schmidt
Charles Baynham
H Evans
Bianca Veglia
Elmer Grundeman
Matthias Germann
Ivan Kosternoy
Bruno Ximenez
Nicolas Pulido Mateo
Sam Hile
Matthew Day
Elia Perego
Fabian...
Trapped ions are a promising basis for quantum computers. They feature excellent quantum gate fidelities, long coherence times, as well as the ability to shuttle the qubits around the processor, enabling near error-free and arbitrary qubit connectivity. As for any quantum hardware implementation, the physical quantum gate set available with trapped ions is limited - in this case with rotation...
Optical atomic frequency standards and clocks are continuing to push the boundaries of precision measurement with fractional frequency uncertainties from systematic offsets now below 1x10$^{-18}$ [1]. With this high level of performance comes the ability to not only carry out precision frequency metrology [2] but also to investigate fundamental physics such as local Lorentz invariance [3] and...
Trapped ions are a promising tool for building a large scale quantum computer. We present work towards a prototype demonstrating the key methods required to realise a scalable trapped-ion quantum computer architecture based on tileable, repeating modules [1].
To find practical applications, quantum computers need to scale significantly. A quantum computing architecture is best constructed...
Two-qubit gates with high fidelities are an essential ingredient to perform universal operations on a quantum information processor.
One promising candidate to implement such a device are trapped ions in microfabricated surface-electrode ion traps as envisioned by the QCCD architecture [1, 2].
In this approach, the quantum information is encoded in the electronic spin states of the ions,...
In CERN’s Alpha Experiment, clouds of positrons and anti-protons are merged to produce anti-hydrogen. The issue of low antimatter yield from this experiment has been addressed by various design alternatives in past, among which a proposal to use a two-frequency ion trap is probably the newest [1]. Here I present a concept of a new experiment that takes this technology and applies it to a...
By exploiting narrow optical transitions in trapped atoms, optical clocks have surpassed the frequency stability and accuracy of caesium microwave clocks, the current standard for the SI second, by up to two orders of magnitude [1]. With more progress on the horizon, it is anticipated that the SI second will soon be redefined in terms of an optical frequency standard [2].
For frequency...
