Quantum Potential Research Articles

2D materials for quantum information science

The transformation of digital computers from bulky machines to portable systems has been enabled by new materials and advanced processing technologies that allow ultrahigh integration of solid-state electronic switching devices. As this conventional scaling pathway has approached atomic-scale dimensions, the constituent nanomaterials (such as SiO2 gate dielectrics, poly-Si floating gates and Co–Cr–Pt ferromagnetic alloys) increasingly possess properties that are dominated by quantum physics. In parallel, quantum information science has emerged as an alternative to conventional transistor technology, promising new paradigms in computation, communication and sensing. The convergence between quantum materials properties and prototype quantum devices is especially apparent in the field of 2D materials, which offer a broad range of materials properties, high flexibility in fabrication pathways and the ability to form artificial states of quantum matter. In this Review, we discuss the quantum properties and potential of 2D materials as solid-state platforms for quantum-dot qubits, single-photon emitters, superconducting qubits and topological quantum computing elements. By focusing on the interplay between quantum physics and materials science, we identify key opportunities and challenges for the use of 2D materials in the field of quantum information science. 2D materials exhibit diverse properties and can be integrated in heterostructures: this makes them ideal platforms for quantum information science. This Review surveys recent progress and identifies future opportunities for 2D materials as quantum-dot qubits, single-photon emitters, superconducting qubits and topological quantum computing elements.

Collisional Depolarization of the Solar Ca, Mg, and Ba Levels

Abstract We study the depolarization of the p-states of the Mg, Ca, and Ba atoms by isotropic collisions with neutral hydrogen. We show that the main source of error in calculating the collisional depolarization is the inaccuracy of the interaction potentials. To better investigate this problem, we determine the region of the interaction potential that is decisive in the calculation of the depolarization rates. We conclude that semiclassical and quantum potentials should be combined in view of obtaining the so-called hybrid potentials, which are the most precise ones. The depolarization rates of the p-states of the Ca i, Mg i, and Ba i are inferred by using hybrid potentials and compared to previously obtained quantum and semiclassical rates. Insights are also given for treating the effects of the spin. Our results should be useful for interpreting the second solar spectrum.

Quantum cosmology of a Hořava–Lifshitz model coupled to radiation

In the present paper, we canonically quantize a homogeneous and isotropic Hořava–Lifshitz cosmological model, with constant positive spatial sections and coupled to radiation. We consider the projectable version of that gravitational theory without the detailed balance condition. We use the Arnowitt–Deser–Misner (ADM) formalism to write the gravitational Hamiltonian of the model and the Schutz variational formalism to write the perfect fluid Hamiltonian. We find the Wheeler–DeWitt equation for the model, which depends on several parameters. We study the case in which parameter values are chosen so that the solutions to the Wheeler–DeWitt equation are bounded. Initially, we solve it using the Many Worlds interpretation. Using wave packets computed with the solutions to the Wheeler–DeWitt equation, we obtain the scalar factor expected value [Formula: see text]. We show that this quantity oscillates between finite maximum and minimum values and never vanishes. Such result indicates that the model is free from singularities at the quantum level. We reinforce this indication by showing that by subtracting one standard deviation unit from the expected value [Formula: see text], the latter remains positive. Then, we use the DeBroglie–Bohm interpretation. Initially, we compute the Bohm’s trajectories for the scale factor and show that they never vanish. Then, we show that each trajectory agrees with the corresponding [Formula: see text]. Finally, we compute the quantum potential, which helps understanding why the scale factor never vanishes.

A proposed mechanism for mind-brain interaction using extended Bohmian quantum mechanics in Avicenna's monotheistic perspective

In quantum approaches to consciousness, the authors try to propose a model and mechanism for the mind-brain interaction using modern physics and some quantum concepts which do not exist in the classical physics. The independent effect of mind on the brain has been one of the challenging issues in the history of science and philosophy. In some recent mind-brain interaction models, the direct influence of mind on matter is either not accepted (as in Stapp's model) or not clear, and there have not been any clear mechanism for it (as in Penrose-Hameroff's model or in Eccles's model). In this manuscript we propose a model and mechanism for mind's effect on the matter using an extended Bohmian quantum mechanics and Avicenna's ideas. We show that mind and mental states can affect brain's activity without any violation of physical laws. This is a mathematical and descriptive model which shows the possibility of providing a causal model for mind's effect on matter. It is shown that this model guarantees the realistic philosophical constraints and respects the laws of nature. In addition, it is shown that it is in agreement with the Libet style experimental results and parapsychological data.To propose this model, we obtained a modified (non-unitary) Schrödinger equation via second quantization method which affects the particle through a modified quantum potential and a new term in the continuity equation. At the second quantized level, which is equivalent to quantum field theory level (QFT), we can use the path integral formalism of Feynman. We show that there are three methods to extend Bohmian QM via path integral formalism, which has different interpretations. By numerical simulation of trajectories in the two-slits experiment, we show their differences and choose one of these methods for our mind-brain model which can be the basis for explaining some phenomena which are not possible to explain in the standard Bohmian QM.

Metric geometry and the determination of the Bohmian quantum potential

A geometric approach to quantum mechanics which is formulated in terms of Finsler geometry is developed. It is shown that quantum mechanics can be formulated in terms of Finsler configuration space trajectories which obey Newton-like evolution but in the presence of an additional kind of potential. This additional quantum potential which was obtained first by Bohm has the consequence of contributing to the forces driving the system. This geometric picture accounts for many aspects of quantum dynamics and leads to a more natural interpretation. It is found for example that dynamics can be accounted for by incorporating quantum effects into the geometry of space-time.

Quantum Unsharpness, Potentiality, and Reality

Paul Busch argued that the positive operator (valued) measure, a generalization of the standard quantum observable, enables a consistent notion of unsharp reality based on a quantifiable degree of reality whereby systems can possess generalized properties jointly, whereas related sharp properties cannot be so possessed (Busch and Jaeger in Found Phys 40:1341, 2010). Here, the work leading up to the formalization of this notion to which he made great contributions is reviewed and explicated in relation to Heisenberg’s notions of potentiality and actuality. The notion of unsharp reality is then extended further by the introduction of a distinction between actual and actualizable elements of reality based on these mathematical innovations.

A thermodynamical derivation of the quantum potential and the temperature of the wave function

In this paper a thermodynamical derivation of the quantum potential is proposed. Within the framework of Bohmian mechanics we show how the quantum potential can be derived, by adding an additional informational degree of freedom to the ordinary degrees of freedom of a physical system. Such a derivation uses the First Law of thermodynamics for this additional degree of freedom and basic equilibrium thermodynamics methods. By doing that, one may associate a temperature to each wave function. Features and behavior of this temperature in different situations is studied.

Black Phosphorus Quantum Dots Induced High‐Quality Perovskite Film for Efficient and Thermally Stable Planar Perovskite Solar Cells

Crystallinity and trap‐state density of a perovskite film play a critical role in the performance of corresponding perovskite solar cells (PVSCs). Herein, liquid‐phase‐exfoliated black phosphorus quantum dots (BPQDs) are incorporated into the perovskite precursor solution as additives to direct the formation of the perovskite film, i.e., methylammonium lead iodide (MAPbI3). It is found that the perovskite films made with BPQDs have higher crystallinity and less nonradiative detects compared with the pristine ones, leading to longer carrier lifetime and higher carrier collection efficiency. Time‐of‐flight secondary‐ion mass spectra and surface density calculation of BPQDs reveal that the improvement of the perovskite film quality may be related to the heterogeneous nucleation of the perovskite film at the BPQDs. PVSCs using MAPbI3 films made with BPQDs achieve a maximum power conversion efficiency of 20.0% and an encouraging thermal stability of T80 = 100 h at 100 °C. Both values are remarkably higher than the devices with pristine perovskite films. Therefore, this work demonstrates the potential of the 2D materials quantum dots‐assisted growth method for high‐performance PVSCs.

New insights into the physical processes that underpin cell division and the emergence of different cellular and multicellular structures

Despite decades of focused research, a detailed understanding of the fundamental physical processes that underpin biological systems (structures and processes) remains an open challenge. Within the present paper we report on biomimetic studies, which offer new insights into the process of cell division and the emergence of different cellular and multicellular structures.Experimental studies specifically investigated the impact of including different concentrations of charged bio-molecules (cytokinin and gibberellic acid) on the growth of BaCO3−SiO2 based structures. Results highlighted the role of charge density on the emergence of long-range order, underpinned by a negentropic process. This included the growth of synthetic cell-like structures, with the intrinsic capacity to divide and change morphology at cellular and multicellular scales.Detailed study of dividing structures supports a hypothesis that cell division is dependent on the establishment of a charge-induced macroscopic quantum potential and cell-scale quantum coherence, which allows a description in terms of a macroscopic Schrödinger-like equation, based on a constant different from the Planck constant. Whilst the system does not reflect full correspondence with standard quantum mechanics, many of the phenomena that we typically associate with such a system are recovered.In addition to phenomena normally associated with the Schrödinger equation, we also unexpectedly report on the emergence of intrinsic spin as a macroscopic quantum phenomena, whose origins we account for within a four-dimensional fractal space-time and a macroscopic Pauli equation, which represents the non-relativistic limit of the Dirac equation.

On geometro dynamics in atomic stationary states

In a previous paper [G.Gomez Blanch and M.J.Fullana, 2017] we dened, in the frame of a geometro-dynamic approach, a metric corresponding to a lorentzian spacetime were the electron stationary trajectories in an hydrogenoid atom, derived from the de Broglie-Bohm model, are geodesics. In this paper we want to complete this purpose: we will determinate the remaining relevant geometrical elements of that approach and we will calculate the energetic density component of the energy-momentum tensor. We will discuss the meaning of the obtained results and their relationship with other geometro-dynamic approaches.Furthermore, we will derive a more general relationship between the lorentzian metric tensor and the wave function for general stationary states. The electron description by the wave function ψ in the Euclidean space and time is shown equivalent to the description by a metric tensor in an lorentzian manifold. In our approach, the particle acquires a determining role over thewave function, in a similar manner as the wave function determines the movement of the particle. This dialectic approach overcomes the de Broglie-Bohm model. And furthermore, a non local element (the quantum potential) is introduced in the model, that therefore goes beyond the relativistic locality.

The Gravity of the Classical Klein-Gordon Field

The work shows that the evolution of the field of the free Klein–Gordon equation (KGE), in the hydrodynamic representation, can be represented by the motion of a mass density ∝ | ψ | 2 subject to the Bohm-type quantum potential, whose equation can be derived by a minimum action principle. Once the quantum hydrodynamic motion equations have been covariantly extended to the curved space-time, the gravity equation (GE), determining the geometry of the space-time, is obtained by minimizing the overall action comprehending the gravitational field. The derived Einstein-like gravity for the KGE field shows an energy-impulse tensor density (EITD) that is a function of the field with the spontaneous emergence of the “cosmological” pressure tensor density (CPTD) that in the classical limit leads to the cosmological constant (CC). The energy-impulse tensor of the theory shows analogies with the modified Brans–Dick gravity with an effective gravity constant G divided by the field squared. Even if the classical cosmological constant is set to zero, the model shows the emergence of a theory-derived quantum CPTD that, in principle, allows to have a stable quantum vacuum (out of the collapsed branched polymer phase) without postulating a non-zero classical CC. In the classical macroscopic limit, the gravity equation of the KGE field leads to the Einstein equation. Moreover, if the boson field of the photon is considered, the EITD correctly leads to its electromagnetic energy-impulse tensor density. The work shows that the cosmological constant can be considered as a second order correction to the Newtonian gravity. The outputs of the theory show that the expectation value of the CPTD is independent by the zero-point vacuum energy density and that it takes contribution only from the space where the mass is localized (and the space-time is curvilinear) while tending to zero as the space-time approaches to the flat vacuum, leading to an overall cosmological effect on the motion of the galaxies that may possibly be compatible with the astronomical observations.

Analytical study of resonant optical solitons with variable coefficients in Kerr and non-Kerr law media

In this article, the extended trial approach has been used for the investigation of traveling wave solutions of resonant nonlinear Schrodinger equation with variable coefficients depending upon time in the presence of different effects such as Kerr law and parabolic law nonlinearity including a Bohm potential term. Many new soliton solutions such as bright, dark, singular and rational function solutions are obtained. This technique proves to be an advantageous and powerful mathematical tool for establishing abundant exact traveling wave solutions in mathematical physics and plasma. The resonant nonlinear Schrodinger’s equation, in specific, governs the propagation of soliton in both quantum potential and uniaxial waves in a cold collisionless plasma.

Quaternion Algebra on 4D Superfluid Quantum Space-Time: Gravitomagnetism

Gravitomagnetic equations result from applying quaternionic differential operators to the energy-momentum tensor. These equations are similar to the Maxwell's EM equations. Both sets of the equations are isomorphic after changing orientation of either the gravitomagnetic orbital force or the magnetic induction. The gravitomagnetic equations turn out to be parent equations generating the following set of equations: (a) the vorticity equation giving solutions of vortices with nonzero vortex cores and with infinite lifetime; (b) the Hamilton-Jacobi equation loaded by the quantum potential. This equation in pair with the continuity equation leads to getting the \Schrodinger equation describing a state of the superfluid quantum medium (a modern version of the old ether); (c) gravitomagnetic wave equations loaded by forces acting on the outer space. These waves obey to the Planck's law of radiation.

Modified Bohm’s theory for abstruse measurements: application to layer depth profiling using auger spectroscopy

Modified Bohm formalism is applied to solve a problem of abstruse layer depth profiles measured by the Auger electron spectroscopy technique in real physical systems, i.e., the desorbed carbon/passive layer on NiTi substrate and the adsorbed oxygen/surface of NiTi alloy. It is shown that abstruse layer profiles may be converted to real layer structures using the modified Bohm theory, where the quantum potential is due to an Auger electron effect. It is also pointed out that the stationary probability density predicts multilayer structures of abstruse depth profiles caused by carbon desorption and oxygen adsorption processes. The criterion for a kind of break between the physical and unphysical multilayer systems was found. We have concluded that the physics is also characterized by the abstruse measurement and the modified Bohm formalism

Quantum Mechanics as a Reactive Probabilistic System

In this paper, we present the quantum mechanics as a reactive system. To show this, “holography” is introduced as a reactive system. Illumination of the object and reference beam create sources (hologram) that are activated by the same reference beam, which is reacted in a way to produce the image. Controlled chemical system reacts to the external or internal change generated new sources (chemical product) that diffuse in the body environment, and establishes a new equilibrium. The droplets bouncing on a vertical vibrating fluid bath that simulates the main quantum phenomena is a reactive system between droplets and vibrating fluid. It is shown that quantum mechanics is a probabilistic reactive system between quantum potential and pseudo kinetic energy in which an integral is the Fisher information. Information and probability are the key points in quantum mechanics. Quantum mechanics can be built by only the probability normalization properties and associated information without assuming any other hypothesis. With joint probability and Fisher information by Euler Lagrange equation, we can find the quantum potential and the continuity equation. With only probability approach, it is possible to give a meaning to the Schrodinger equation without any thermo-dynamical model of quantum mechanics. The reactive system can be denoted as a morphogenetic system where the form is generated by some designed rules or properties.

Linearity Distortion Assessment and Small-Signal Behavior of Nano-Scaled SOI MOSFET for Terahertz Applications

Fully-Depleted Silicon-on-Insulator (FD SOI) MOS technology has already been reported as a strong contender in nanoscale CMOS designs. This work presents the linearity-distortion assessment, small-signal and radio-frequency noise-behavior of dual-metal-insulated-gate (DMIG) source-engineered (SE) FD SOI MOSFET for terahertz (THz) applications. Here, linearity-distortion performance has been monitored on the basis of numerical calculations of transconductance and its higher-order derivatives along with the voltage-intercept points, and various parameters of intermodulation-distortion. This analysis also practices the guidelines of device design with least linearity-distortion in radio-frequency integrated-circuits based communication systems at 50 nm technology node. Further, the small-signal and RF noise-behavior have been examined on the basis of high-frequency scattering-parameters for the analysis of input/output reflection-coefficients (S11/S22), reverse/forward transmission-coefficients (S12/S21), Stern's-stability-factor (K), minimum noise-figure, noise-conductance and cross-correlation factor (<VN-in.VN-out*>). The analysed results affirm the ultimate reduction in reflection-coefficients and a significant increase in transmission-coefficients in case of DMIG FD SOI MOSFET at THz range as compared to existing MOS structures. Also, the analysis reveals the considerable reduction in various radio-frequency noise FOMs and thus represents the device efficacy in low-noise-amplifiers. All these studies have been carried out by performing numerical simulations over TCAD-ATLAS simulator from Silvaco along with quantum-mechanical-effect (QME) and Bohm-quantum-potential (BQP) models.

Wheeler--DeWitt Universe Wave Function in the Presence of Stiff Matter

We study the Wheeler-DeWitt (WDW) equation close to the Big-Bang. We argue that an interaction dominated fluid (speed of sound equal to the speed of light), if present, would dominate during such an early phase. Such a fluid with $p=\rho\propto1/a^{6}$ generates a term in the potential of the wave function of the WDW equation proportional to $-1/a^{2}.\ $This very peculiar quantum potential, which embodies a spontaneous breaking of dilatation invariance, has some very remarkable consequences for the wave function of the Universe: $\Psi(a)$ vanishes at the Big-Bang: $\Psi(0)=0$; the wave function $\Psi(a)$ is always real; a superselection rule assures that the system is confined to $a\geq0$ without the need of imposing any additional artificial barrier for unphysical negative $a$. These results do not depend on the operator-ordering problem of the WDW equation.

Simondon and Quantum Mechanics (or, On How the ‘Preindividual’ Hypothesis Leads to a Realistic but Non-Substantialist Interpretation of the Orthodox Quantum Formalism)

In this paper, we propose a Simondonian interpretation of quantum mechanics taking as a standpoint his “preindividual hypothesis” in order to consider the problem of contextuality. We will examine whether the epistemological obstacle produced by the notion of entity can be bypassed by specifying, according to Simondon and the Kochen-Specker Theorem, the mode of existence of quantum potentialities.

Tunneling through bridges: Bohmian non-locality from higher-derivative gravity

A classical origin for the Bohmian quantum potential, as that potential term arises in the quantum mechanical treatment of black holes and Einstein–Rosen (ER) bridges, can be based on 4th-order extensions of Einstein's equations. The required 4th-order extension of general relativity is given by adding quadratic curvature terms with coefficients that maintain a fixed ratio, as their magnitudes approach zero, with classical general relativity as a singular limit. If entangled particles are connected by a Planck-width ER bridge, as conjectured by Maldacena and Susskind, then a connection by a traversable Planck-scale wormhole, allowed in 4th-order gravity, describes such entanglement in the ontological interpretation. It is hypothesized that higher-derivative gravity can account for the nonlocal part of the quantum potential generally.

Invariance in Transverse Momentum of Photons in Double-slit Experiment

One of the intriguing mystery in modern physics is the quantum interference phenomena, which the behaviour of photons in double-slit experiment is still ambiguous. Instead of relying on the naive probabilistic point of view, Bohmian mechanics provides the ground base for interpreting quantum system in a deterministic way closely related to classical mechanics such as it constructs the photon trajectory for the double-slit set up. The appearance on the bending in the constructed photon trajectory seem to contravene the notable law of conservation of momentum. Here, we report on conservation of the transverse momentum of photon trajectories based on numerical solution of Bohmian mechanics in double-slit set up for single photon, pair of photons and ensemble of photons until interference pattern is produced. It is shown that the total transverse momentum in the system of Bohmian mechanics is invariance due to the non-local action of quantum potential.