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Here, we propose a device that can strongly reduce the Gravitational Mass of a body. Basically, it contains a thin layer of Photon Gas, between the plates of a capacitor, produced by lasers conveniently positioned. By controlling the value of the gravitational mass of the Photon gas, by means of the electric field produced by the capacitor, it is possible to control the Gravitational Mass of a body, when it is placed upon the photon gas. From the technical point of view this device can be used to strongly reduce the gravitational masses of aircrafts or spacecrafts.

The LUXE experiment is a new experiment in planning in Hamburg, which will study Quantum Electrodynamics at the strong-field frontier. LUXE intends to measure the positron production rate in this unprecedented regime by using, among others, a silicon tracking detector. The large number of expected positrons traversing the sensitive detector layers results in an extremely challenging combinatorial problem, which can become computationally expensive for classical computers. This paper investigates the potential future use of gate-based quantum computers for pattern recognition in track reconstruction. Approaches based on a quadratic unconstrained binary optimisation and a quantum graph neural network are investigated in classical simulations of quantum devices and compared with a classical track reconstruction algorithm. In addition, a proof-of-principle study is performed using quantum hardware., Comment: 15 pages, 12 figures

In superconductors, vortices induced by a magnetic field are nucleated where some random fluctuations determine the nucleation position, and then may be pinned by impurities or boundaries, impeding the development of vortex-based quantum devices. Here, we propose a superconducting structure, which allows to nucleate and control vortices on-demand by controlling magnetic fields and currents. Using time-dependent Ginzburg-Landau theory, we study a driven vortex motion in two-dimensional Corbino geometries of superconductor-normal metal-superconductor Josephson junctions. We remedy the randomness of nucleation by introducing normal conducting rails to the Corbino disk to guide the nucleation process and motion of vortices towards the junction. We elaborate on the consequences of rail-vortex and vortex-vortex interactions to the quantization of resistance across the junction. Finally, we simulate the nucleations and manipulations of two and four vortices in Corbino networks, and discuss its application to Majorana zero mode braiding operations. Our study provides a potential route towards quantum computation with non-Abelian anyons.

A fully analytical surface potential and current–voltage model is presented for the first time for both lateral homojunction (HMJ) and heterojunction (HTJ) tunneling-field-effect transistors (TFETs) based on 2-D semiconducting channel materials. The dynamic gate-modulated electrostatic potential at the source/channel tunneling junction is suitably captured by solving a quasi-2-D Poisson’s equation in both source and channel. Subsequently, the band-to-band tunneling current is accurately derived starting from the Landauer’s equation by integrating over all possible carrier energies (or wave-vectors) over which tunneling is possible. The model employs Fermi–Dirac statistics in both the degenerate source and drain to compute the surface potential and net current, which yields more physical results than the commonly employed Boltzmann statistics. Its use in Landauer’s approach for evaluating the net ON-current leads to an analytical model of the TFET, which physically guarantees zero drain current at zero drain–source bias. Input and output characteristics for both HMJ and HTJ TFETs are computed and compared against rigorous nonequilibrium Green’s function (NEGF) simulations for different device parameters to prove the veracity of the model, and the match has been found to be excellent up to ultrashort channel length of 5 nm.

Atomtronics deals with matter-wave circuits of ultracold atoms manipulated through magnetic or laser-generated guides with different shapes and intensities. In this way, new types of quantum networks can be constructed in which coherent fluids are controlled with the know-how developed in the atomic and molecular physics community. In particular, quantum devices with enhanced precision, control, and flexibility of their operating conditions can be accessed. Concomitantly, new quantum simulators and emulators harnessing on the coherent current flows can also be developed. Here, the authors survey the landscape of atomtronics-enabled quantum technology and draw a roadmap for the field in the near future. The authors review some of the latest progress achieved in matter-wave circuits' design and atom-chips. Atomtronic networks are deployed as promising platforms for probing many-body physics with a new angle and a new twist. The latter can be done at the level of both equilibrium and nonequilibrium situations. Numerous relevant problems in mesoscopic physics, such as persistent currents and quantum transport in circuits of fermionic or bosonic atoms, are studied through a new lens. The authors summarize some of the atomtronics quantum devices and sensors. Finally, the authors discuss alkali-earth and Rydberg atoms as potential platforms for the realization of atomtronic circuits with special features., AVS Quantum Science, 3 (3)

The nanoscale silicon electronic devices are the fundamental building blocks for the modern integrated circuitry that powers the personal computer, smart phone, advanced car sensor or biomedical implant. Besides these great contributions to our daily life, they also provide excellent host enviroment for the physics experiments, in which the properties of individual charge or spin can be investigated. In this thesis, we investigated silicon nanoelectronic devices that have important applications in the field of quantum electrical current metrology and quantum information processing. First, we implmeneted an extremely accurate gigahertz silicon-based single-electron(SE) pump for the redefinition of the International Standard unit for the electrical current, Ampere. This device can reconstruct macroscopic measurable dc current by transfer individual electrons in pace with an exeternal drive signal. In a measurement with tracebility back to the primary voltage and resistance standards, we found the device current closely matched the target value within a total uncertainty of about 0.3 parts-per-million. Up to date, this is the most accurate electrical measurement ever performed on the current of a silicon device. In addition, through the theoretical analysis the current plateau, we estimate the upperbound of the dominate thermal error of our pump could be as low as 4 parts-per-billion. This implies our device could have already satisfied the stringent accuracy criteria of the redefinition of Ampere. Next, we choose to assess the accuracy of our pump in parts-per-billion regime through the error-counting approach. We revise the fabrication recipe for the Al single-electron-transitor~(SET) that can be used as on-chip integrated error counter for the SE pumps. Through both the room-temperature probing test as well as millikelvin temperature measurement, we found the revision significantly improved the yield and the quality of the sensor. We also successfully fabricated the pump-sensor integrated devices. In a preliminary study, we observed a large amplitude fluctuation in the sensor reading once the reservoir dot is induced. We hypothesize this is caused by the free-movement of electrons in the micron-size dot and call for future study to confirm this theory. Finally, we developed a Complementary-Metal-Oxide-Semiconductor (CMOS) compatible process to create a Schottky-barrier MOS Field-Effect-Transistor (SBMOSFET) for the signal amplification of silicon quantum electronic devices at cryogenic temperature. We found the SBMOSFET operated as a p-MOS tunnel-FET at low temperature. Based on the electric field calculated through the commercial software TCAD, we successfully replicated the current profile of SBMOSFET that is in good agreement with the cryogenic measurement result.

We present niobium-based Josephson devices as prototypes for applications to quantum computation with flux qubits. The most interesting feature of this device is the use of a Josephson vertical interferometer for a fine tuning of flux qubit and interquibit coupling. These devices allow a control of the off-diagonal Hamiltonian terms of flux qubit and of the flux transfer function of a superconducting transformer. In the vertical interferometer, the Josephson current is precisely modulated from a maximum to zero with fine control and precision by a small transversal magnetic field parallel to the radio-frequency superconducting loop plane and to the flux transformer. © 2005 American Institute of Physics. *DOI: 10.1063/1.2115083*

We switch the transport along different paths in a system constituted by a phosphorus donor in a silicon quantum dot in complementary metal-oxide-semiconductor technology, coupled with two donors at the source side. The standard Coulomb blockade pattern created by the transport through the D0 neutral state of an individual donor located in the channel of the device is modified by two additional randomly diffused nearby donors. By varying the control voltages, the fin-field effect transistor acts as a quantum device which may be used to control alternative current paths through different donors.