A5056474704- Quantum Information and Cryptography
- Quantum Computing Algorithms and Architecture
- Quantum and electron transport phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum optics and atomic interactions
- Quantum Mechanics and Applications
- Atomic and Subatomic Physics Research
- Neural Networks and Reservoir Computing
- Advanced Thermodynamics and Statistical Mechanics
- Advanced Frequency and Time Standards
- Quantum-Dot Cellular Automata
- Spectroscopy and Quantum Chemical Studies
- Mass Spectrometry Techniques and Applications
- Low-power high-performance VLSI design
- Mechanical and Optical Resonators
- Ion-surface interactions and analysis
- Optical Network Technologies
- Electrochemical Analysis and Applications
- Analytical chemistry methods development
University of Sussex
2013-2022
Centre for Quantum Technologies
2022
Qu & Co. (Netherlands)
2022
The availability of a universal quantum computer may have fundamental impact on vast number research fields and society as whole. An increasingly large scientific industrial community is working toward the realization such device. arbitrarily best be constructed using modular approach. We present blueprint for trapped ion-based scalable module, making it possible to create architecture based long-wavelength radiation gates. modules control all operations stand-alone units, are silicon...
STIRAP (Stimulated Raman Adiabatic Passage) is a powerful laser-based method, usually involving two photons, for efficient and selective transfer of population between quantum states. A particularly interesting feature the fact that coupling initial final states via an intermediate state even though lifetime latter can be much shorter than interaction time with laser radiation. Nevertheless, spontaneous emission from prevented by interference. Maintaining coherence throughout process...
Trapped ions are a promising tool for building large-scale quantum computer. However, the number of required radiation fields realization gates in any proposed ion-based architecture scales with within computer, posing major obstacle when imagining device millions ions. Here, we present fundamentally different approach trapped-ion computing where this detrimental scaling vanishes. The method is based on individually controlled voltages applied to each logic gate location facilitate actual...
System scalability is fundamental for large-scale quantum computers (QCs) and being pursued over a variety of hardware platforms. For QCs based on trapped ions, architectures such as the charge-coupled device (QCCD) are used to scale number qubits single device. However, ions that can be hosted computing module limited by size chip used. Therefore, modular approach critical importance requires connections between individual modules. Here, we present demonstration matter-link in which ion...
Constructing a large scale ion trap quantum processor will require entangling gate operations that are robust in the presence of noise and experimental imperfection. We experimentally demonstrate how new type M{\o}lmer-S{\o}rensen protects against infidelity caused by heating motional mode used during gate. Furthermore, we show same technique simultaneously provides significant protection slow fluctuations mis-sets secular frequency. Since this parameter sensitivity is worsened cases where...
Many schemes for implementing quantum information processing require that the atomic states used have a non-zero magnetic moment, however such magnetically sensitive of an atom are vulnerable to decoherence due fluctuating fields. Dressing with external field is powerful method reducing [N. Timoney et al., Nature 476, 185], even if being dressed strongly coupled environment. We introduce experimentally simpler manipulating dressed-state qubit, which allows implementation general rotations...
We demonstrate a method for preparing and detecting all eigenstates of three-level microwave dressed system with single trapped ion. The significantly reduces the experimental complexity gate operations dressed-state qubits, as well allowing three dressed-states to be prepared detected, thereby providing access qutrit that is protected from magnetic field noise. In addition, we individual addressing clock transitions in two ions using strong static gradient, showing our can used prepare...
In recent decades there has been a rapid development of methods to experimentally control individual quantum systems. A broad range developed for two-level systems, however the complexity multi-level systems make analogous extremely challenging. Here, we exploit equivalence between with SU(2) symmetry and spin-1/2 develop technique generating new robust, high-fidelity, methods. As demonstration this technique, adiabatic composite realise these using an $^{171}$Yb$^+$ ion system. We measure...
We investigate how hardware specifications can impact the final run time and required number of physical qubits to achieve a quantum advantage in fault tolerant regime. Within particular frame, both code cycle achievable may vary by orders magnitude between different designs. start with logical resource requirements corresponding for chemistry application, simulating FeMo-co molecule, explore what extent slower times be mitigated using additional qubits. show that certain situations,...
A major obstacle in the way of practical quantum computing is achieving scalable and robust high-fidelity entangling gates. To this end, control has become an essential tool, as it can make interaction resilient to sources noise. Nevertheless, may be difficult identify appropriate technique for a particular need given breadth work pertaining entanglement. we attempt consolidate literature by providing non-exhaustive summary critical analysis. The methods are separated into two categories:...
Applying a magnetic field gradient to trapped ion allows long-wavelength microwave radiation produce mechanical force on the ion's motion when internal transitions are driven. We demonstrate such coupling using single \Yb{171}~ion, and use it entanglement between spin motional state, an essential step towards implement multi-qubit operations.
Recent studies using the quantum information theoretic approach to thermodynamics show that presence of coherence in systems generates corrections classical fluctuation theorems. To explicate physical origins and implications such corrections, we here convert an abstract framework autonomous Crooks relation into equalities for well-known coherent, squeezed cat states. We further provide a proposal concrete experimental scenario test these equalities. Our scheme consists evolution trapped ion...
We demonstrate ground-state cooling of a trapped ion using radio-frequency (RF) radiation. This is powerful tool for the implementation quantum operations, where RF or microwave radiation instead lasers used motional state engineering. measure mean phonon number $\overline{n} = 0.13(4)$ after sideband cooling, corresponding to occupation probability 88(7)\%. After preparing in vibrational ground state, we engineering by driving Rabi oscillations between n=0 and n=1 Fock states. also use...
A proposal for a phase gate and M{\o}lmer-S{\o}rensen (MS) in the dressed state basis is presented. In order to perform multi-qubit interaction, strong magnetic field gradient required couple phonon-bus qubit states. The performed using resonant microwave driving fields together with either radio-frequency (RF) field, or additional detuned fields. robust ambient fluctuations due an applied field. Furthermore, Rabi frequency decoupled from phonon dephasing RF This makes this new attractive...
Abstract The cost of enabling connectivity in noisy intermediate‐scale quantum (NISQ) devices is an important factor determining computational power. A qubit routing algorithm created, which enables efficient global a previously proposed trapped ion computing architecture. characterized by comparison against both strict lower bound, and positional swap based algorithm. An error model proposed, can be used to estimate the achievable circuit depth volume device as function experimental...
Abstract Microfabricated ion-trap devices offer a promising pathway towards scalable quantum computing. Research efforts have begun to focus on the engineering challenges associated with developing large-scale arrays and networks. However, increasing size of array integrating on-chip electronics can drastically increase power dissipation within chips. This leads an in operating temperature limits device performance. Therefore, effective thermal management is essential consideration for any...
Abstract A major challenge for quantum computers is the scalable simultaneous execution of gates. One approach to address this in trapped ion implementation gates based on static magnetic field gradients and global microwave fields. In paper, we present fabrication surface traps with integrated copper current carrying wires embedded inside substrate below trap electrodes, capable generating high gradients. The layer’s measured sheet resistance 1.12 mΩ/sq at room temperature sufficiently low...
We propose a σz ⊗ laser-free entangling gate which uses the intrinsic J-coupling of ions in static magnetic gradient. Dephasing interaction is suppressed by means continuous dynamical decoupling using pairs microwave fields. The virtually insensitive to common amplitude noise fields and enables high fidelities despite qubit frequency fluctuations, while interaction's inherent robustness motional decoherence retained. Errors far below fault-tolerant threshold can be achieved at initial...
We investigate how hardware specifications can impact the final run time and required number of physical qubits to achieve a quantum advantage in fault tolerant regime. Within particular frame, both code cycle achievable may vary by orders magnitude between different designs. start with logical resource requirements corresponding for chemistry application, simulating FeMoco molecule, explore what extent slower times be mitigated using additional qubits. show that certain situations...
Hyperfine energy levels in trapped ions offer long-lived spin states. In addition, the motion of these charged particles couples strongly to external electric field perturbations. These characteristics make attractive platforms for quantum sensing fields. However, states do not exhibit a strong intrinsic coupling This limits achievable sensitivities. Here, we amplify between perturbations and by using static magnetic gradient. Displacements ion resulting from forces experienced an applied...