Simulating polaron biophysics with Rydberg atoms

Transport of excitations along proteins can be formulated in a quantum physics context, based on the periodicity and vibrational modes of the structures. Exact solutions are very challenging to obtain on classical computers, however, approximate solutions based on the Davydov ansatz have demonstrated the possibility of stabilized solitonic excitations along the protein. We propose an alternative study based on a chain of ultracold atoms. We investigate the experimental parameters to control such a quantum simulator based on dressed Rydberg atoms. We show that there is a feasible range of parameters where a quantum simulator can directly mimic the Davydov equations and their solutions. Such a quantum simulator opens up new directions for the study of transport phenomena in a biophysical context.Transport of excitations along proteins can be formulated in a quantum physics context, based on the periodicity and vibrational modes of the structures. Exact solutions are very challenging to obtain on classical computers, however, approximate solutions based on the Davydov ansatz have demonstrated the possibility of stabilized solitonic excitations along the protein. We propose an alternative study based on a chain of ultracold atoms. We investigate the experimental parameters to control such a quantum simulator based on dressed Rydberg atoms. We show that there is a feasible range of parameters where a quantum simulator can directly mimic the Davydov equations and their solutions. Such a quantum simulator opens up new directions for the study of transport phenomena in a biophysical context

Matter-wave analog of an optical random laser

The accumulation of atoms in the lowest energy level of a trap and the subsequent out-coupling of these atoms is a realization of a matter-wave analog of a conventional optical laser. Optical random lasers require materials that provide optical gain but, contrary to conventional lasers, the modes are determined by multiple scattering and not a cavity. We show that a Bose-Einstein condensate can be loaded in a spatially correlated disorder potential prepared in such a way that the Anderson localization phenomenon operates as a band-pass filter. A multiple scattering process selects atoms with certain momenta and determines laser modes which represents a matter-wave analog of an optical random laser.Comment: 4 pages, 3 figures version accepted for publication in Phys. Rev. A; minor changes, the present title substituted for "Atom Random Laser

Rydberg dressing of a one-dimensional Bose-Einstein condensate

We study the influence of Rydberg-dressed interactions in a one-dimensional (1D) Bose-Einstein condensate (BEC). We show that a 1D geometry offers several advantages over a three-dimensional geometry for observing BEC Rydberg dressing. The effects of dressing are studied by investigating collective BEC dynamics after a rapid switch-off of the Rydberg dressing interaction. The results can be interpreted as an effective modification of the s-wave scattering length. We include this modification in an analytical model for the 1D BEC and compare it to numerical calculations of Rydberg dressing under realistic experimental conditions.</p

Dark soliton in a disorder potential

We consider dark soliton in a Bose-Einstein condensate in the presence of a weak disorder potential. Deformation of the soliton shape is analyzed within the Bogoliubov approach and by employing expansion in eigenstates of the P\"oschl-Teller Hamiltonian. Comparison of the results with the numerical simulations indicates that the linear response analysis reveals good agreement even if the strength of the disorder is of the order of the chemical potential of the system. In the second part of the paper we concentrate on quantum nature of the dark soliton and demonstrate that the soliton may reveal Anderson localization in the presence of a disorder. The Anderson localized soliton may decay due to quasi-particle excitations induced by the disorder. However, we show that the corresponding lifetime is much longer than condensate lifetime in a typical experiment.Comment: 10 pages, 3 figures, version accepted for publication in Phys. Rev.

Tailoring Anderson localization by disorder correlations in 1D speckle potentials

We study Anderson localization of single particles in continuous, correlated, one-dimensional disordered potentials. We show that tailored correlations can completely change the energy-dependence of the localization length. By considering two suitable models of disorder, we explicitly show that disorder correlations can lead to a nonmonotonic behavior of the localization length versus energy. Numerical calculations performed within the transfer-matrix approach and analytical calculations performed within the phase formalism up to order three show excellent agreement and demonstrate the effect. We finally show how the nonmonotonic behavior of the localization length with energy can be observed using expanding ultracold-atom gases

Modern applications of machine learning in quantum sciences

In these Lecture Notes, we provide a comprehensive introduction to the most recent advances in the application of machine learning methods in quantum sciences. We cover the use of deep learning and kernel methods in supervised, unsupervised, and reinforcement learning algorithms for phase classification, representation of many-body quantum states, quantum feedback control, and quantum circuits optimization. Moreover, we introduce and discuss more specialized topics such as differentiable programming, generative models, statistical approach to machine learning, and quantum machine learning

The influence of grinding speed on the creep-feed grinding process

Grinding is usually the last stage of the technological process and determines the quality of manufactured products. One of the varieties of grinding more and more often used in practice is deep grinding which is called Creep-Feed Grinding. It is characterized by a high value of grinding infeed and slow feed. Technological parameters such as the depth of grinding and the speed of feed have a significant impact on the quality of the workpiece. However, also the grinding speed has an influence on the grinding process and the result of machining. Therefore, experimental studies on the impact of grinding speed on the surface roughness and grinding force components were carried out. The tests were realized in the deep-grinding grinding process of Inconel 718 with a grinding wheel made of mixture of sintered alumina and ruby corundum

OCL as the Query Language for UML Model Execution *

Abstract. Despite the specification of OCL mentions “query language ” as one of its possible applications, there are rather few efforts in that direction. However, the problem becomes central where applying MDA to data intensive application modelling is considered. Recently added UML elements of Actions and Structured Activities make it possible to represent a level of detail similar to the one of common programming languages, but data processing requires adequate querying capability as well. As the OMG specification of the UML family, the Object Constraint Language becomes the most obvious candidate to serve this purpose. In this paper we research this role of OCL. Especially, we address the issues of seamless integration with UML metamodel and the useful features of query languages that are missing from OCL

Wire edm cutting strategy impact on the accuracy of blade fir tree root

W artykule przedstawiono dobór strategii i parametrów obróbki w procesie wycinania elektroerozyjnego WEDM (Wire Electrical Discharge Machining) zamka łopatki silnika lotniczego wykonanego z żarowytrzymałego stopu Inconel 718. Obróbkę zaprogramowano z wykorzystaniem modułu WEDM oprogramowania Siemens NX10 i wykonano na wycinarce elektroerozyjnej Mitsubishi FA 10S. Następnie przeprowadzono pomiary chropowatości powierzchni oraz zweryfikowano dokładność kształtu wyciętych zamków łopatki w oparciu o profil wygenerowany z oprogramowania NX10. Otrzymane wyniki badań wstępnych, pozwoliły osiągnąć część założonych wymagań, co potwierdza słuszność podjęcia tematu i kontynuacji badań nad zastosowaniem wycinania elektroerozyjnego WEDM do obróbki elementów silnika lotniczego.The article presents the selection of machining strategy and parameters in wire electrical discharge machining (WEDM) of blade fir tree root made of Inconel 718. Machining was programmed using WEDM module of Siemens NX10 software and conducted on WEDM machine Mitsubishi FA 10S. Furthermore, the measurements of surface roughness and comparison of shape accuracy with the profile generated from the NX10 software were performed. The results of preliminary research allowed to achieve some of the established requirements, which confirms the importance of undertaken subject and to continue research into the use of WEDM in manufacturing aircraft engine components