Polar molecules are an emerging platform for quantum technologies based on their long-range electric dipole--dipole interactions, which open new possibilities information processing and the simulation of strongly correlated systems. Here, we use magnetic microwave fields to design a fast entangling gate with $>0.999$ fidelity is robust respect fluctuations in trapping control small thermal excitations. These results establish feasibility build scalable processor broad range molecular species...

Abstract Breast cancer remains a significant global health concern, and machine learning algorithms computer-aided detection systems have shown great promise in enhancing the accuracy efficiency of mammography image analysis. However, there is critical need for large, benchmark datasets training deep models breast detection. In this work we developed Mammo-Bench, large-scale dataset images, by collating data from seven well-curated resources, viz ., DDSM, INbreast, KAU-BCMD, CMMD, CDD-CESM,...

Hamiltonian encoding is a methodology for revealing the mechanism behind dynamics governing controlled quantum systems. In this paper, following Mitra and Rabitz \cite{abhra_1}, we define via pathways of eigenstates that describe evolution system, where each pathway associated with complex-valued amplitude corresponding to term in Dyson series. The system determined by constructive destructive interference these amplitudes. Pathways similar attributes can be grouped together into classes....

A robust control over quantum dynamics is of paramount importance for technologies. Many the existing techniques are based on smooth Hamiltonian modulations involving repeated calculations basic unitaries resulting in time complexities scaling rapidly with length sequence. Here we show that bang-bang controls need one-time calculation and hence scale much more efficiently. By employing a global optimization routine such as genetic algorithm, it possible to synthesize not only highly...

Cooling the qubit into a pure initial state is crucial for realizing fault-tolerant quantum information processing. Here we envisage star-topology arrangement of reset and computation qubits this purpose. The cool or purify by transferring its entropy to heat-bath with help algorithmic cooling procedure. By combining standard NMR methods powerful control techniques, central two large star topology systems, 13 37 spins respectively. We obtain polarization enhancements factor over 24, an...

An approach is presented for robustness analysis and quantum (unitary) control synthesis based on the classic method of averaging. The result a multicriterion optimization competing nominal (uncertainty-free) fidelity with well known measure: size an interaction (error) Hamiltonian, essentially first term in Magnus expansion unitary. Combining this fact that topology landscape at high determined by null space Hessian, we arrive new two-stage algorithm. Once sufficiently high, approximate...

Abstract The task of testing whether quantum theory applies to all physical systems and scales requires considering situations where a probe interacts with another system that need not obey in full. Important examples include the cases mass probes gravitational field, for which unique gravity does yet exist, or such as light, macroscopic system, biological molecule, may unitary theory. In this context class experiments has recently been proposed, non-classicality (the field) can be tested...

The universal quantum homogenizer can transform a qubit from any state to other with arbitrary accuracy, using only unitary transformations perform this task. Here we present an implementation of finite nuclear magnetic resonance (NMR), four-qubit system. We compare the homogenization mixed pure and reverse process. After accounting for effects decoherence in system, find experimental results be consistent theoretical symmetry how states evolve two cases. analyze implications by interpreting...

We consider the problem of selectively controlling couplings in a practical quantum processor with always-on interactions that are diagonal computational basis, using sequences local not gates. This methodology is well known nuclear magnetic resonance implementations, but previous approaches do scale efficiently for general fully connected Hamiltonian, where complexity finding time-optimal solutions makes them only up to few tens qubits. Given rapid growth number qubits cutting-edge...

A powerful control method in experimental quantum computing is the use of spin echoes, employed to select a desired term system's internal Hamiltonian, while refocusing others. Here, we address more general problem, describing not only turn on and off particular interactions but also rescale their strengths so that can generate any effective Hamiltonian. We propose an algorithm based linear programming for achieving time-optimal rescaling solutions fully coupled systems tens qubits, which be...

Abstract All NMR experiments require sequences of RF ‘pulses’ to manipulate nuclear spins. Signal is lost due non-uniform excitation spins resonating at different energies (chemical shifts) and inhomogeneity in the actually generated by hardware over sample volume. Here, we present Seedless, a tool calculate pulses that compensate for these effects enhance control magnetisation boost signal. The calculations take only few seconds using an optimised GRadient Ascent Pulse Engineering (GRAPE)...

Hamiltonian encoding is a methodology for revealing the mechanism behind dynamics governing controlled quantum systems. In this paper, following Mitra and Rabitz [Phys. Rev. A 67, 033407 (2003)], we define via pathways of eigenstates that describe evolution system, where each pathway associated with complex-valued amplitude corresponding to term in Dyson series. The system determined by constructive destructive interference these amplitudes. Pathways similar attributes can be grouped...

The control of quantum systems has been proven to possess trap-free optimization landscapes under the satisfaction proper assumptions. However, many details landscape geometry and their influence on search efficiency still need be fully understood. This paper numerically explores path-connectedness globally optimal solutions forming top manifold landscape. We randomly sample a plurality controls in assess existence continuous path at that connects two arbitrary solutions. It is shown for...

Benford's Law is an empirical law which predicts the frequency of significant digits in databases corresponding to various phenomena, natural or artificial. Although counter intuitive at first sight, it a higher occurrence digit 1, and decreasing occurrences other larger digits. Here we report Benford analysis NMR draw several interesting inferences. We observe that, general, signals follow distribution time-domain as well domain. Our survey included nuclear species wide variety molecules...

Matrix exponentiation (ME) is widely used in various fields of science and engineering. For example, the unitary dynamics quantum systems described by Hamiltonian operators. However, despite a significant attention, numerical evaluation ME remains computationally expensive, particularly for large dimensions. Often this process becomes bottleneck algorithms requiring iterative ME. Here we propose method approximating single operator with bounded coefficient into product certain discrete This...

As computer technology continues to change, today, it's becoming more imperative find Interactions with systems that are innovative and relevant. Every day, society becomes dependent upon it. Touch screens used on every device but the isn't cheap for application. Interactive modules such as Object Tracking, Gestures will allow us use a virtual mouse instead of physical example. An Tracking application be created interface system. The proposed system employs vision engine move pointer based...

Since 2005 there has been a huge growth in the use of engineered control pulses to perform desired quantum operations systems such as NMR information processors. These approaches, which build on original gradient ascent pulse engineering (GRAPE) algorithm, remain computationally intensive because need calculate matrix exponentials for each time step pulse. Here we discuss how propagators can be approximated using Trotter--Suzuki formula, and further speed up achieved by avoiding unnecessary...

Received 13 December 2019DOI:https://doi.org/10.1103/PhysRevA.101.019902©2020 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasQuantum controlQuantum error correctionQuantum information architectures & platformsTechniquesNuclear magnetic resonanceCondensed Matter, Materials Applied PhysicsQuantum Information