arXiv subjects

Ross D. Hoehn

Publications and source records attributed to Ross D. Hoehn.

6 recordsLinked to original sources

arXiv2018

Effects of Hawking radiation on the entropic uncertainty in a Schwarzschild space-time

Heisenberg uncertainty principle describes a basic restriction on observer's ability of precisely predicting the measurement for a pair of non-commuting observables, and virtually is at the core of quantum mechanics. We herein aim to study entropic uncertainty relation under the background of the Schwarzschild black hole and its control. Explicitly, we develop dynamical features of the measuring uncertainty via entropy in a practical model where a stationary particle interacts with its surrounding environment while another particle --- serving as a quantum memory reservoir --- undergoes freefall in the vicinity of the event horizon of the Schwarzschild space-time. It shows higher Hawking temperatures would give rise to an inflation of the entropic uncertainty on the measured particle. This is suggestive the measurement uncertainty is strongly correlated with degree of mixing present in the evolving particles. Additionally, based on information flow theory, we provide a physical interpretation for the observed dynamical behaviors related with the entropic uncertainty in such a realistic scenario. Finally, an efficient strategy is proposed to reduce the uncertainty by non-tracing-preserved operations. Therefore, our explorations may improve the understanding of the dynamic entropic uncertainty in a curved space-time, and illustrate predictions of quantum measurements in relativistic quantum information sciences.

quant-ph↗

arXiv2018

Canonical Schottky barrier heights of the transition metal dichalcogenide monolayers in contact with a metal

The transition metal dichalcogenide ($MX_{2}$, where $M$=Mo, W and $X$=S, Se, Te) monolayers are of high interest for semiconducting applications at the nanoscale level; this interest is due to both their direct band gaps and high charge mobilities. In this regard, an in-depth understating of the related Schottky barrier heights, associated with the incorporation of $MX_{2}$ sheets into novel low-dimensional metal-semiconductor junctions, is of crucial importance. Herein, we generate and provide analysis of the Schottky barrier heights behavior to account for the metal-induced gap states concept as its explanation. In particular, the present investigations concentrate on the estimation of the charge neutrality levels directly by employing the primary theoretical model, $i.e.$ the cell-averaged Green's function formalism combined the complex band structure technique. The results presented herein place charge neutrality levels in the vicinity of the mid-gap; this is in agreement with previous reports and analogous to the behavior of three-dimensional semiconductors. The calculated canonical Schottky barrier heights are also found to be in agreement with other computational and experimental values in cases where the difference between electronegativities of the semiconductor and metal contact is small. Moreover, the influence of the spin-orbit effects is herein considered and supports that Schottky barrier heights have metal-induced gap state-derived character, regardless whether spin-orbit coupling interactions are considered. The results presented within this report constitute a direct and vital verification of the importance of metal-induced gap states in explaining the behavior of observed Schottky barrier heights at $MX_{2}$-metal junctions.

cond-mat.mes-hall↗

arXiv2017

Entropic uncertainty relations for Markovian and non-Markovian processes under a structured bosonic reservoir

The uncertainty relation is a fundamental limit in quantum mechanics and is of great importance to quantum information processing as it relates to quantum precision measurement. Due to interactions with the surrounding environment, a quantum system will unavoidably suffer from decoherence. Here, we investigate the dynamic behaviors of the entropic uncertainty relation of an atom-cavity interacting system under a bosonic reservoir during the crossover between Markovian and non-Markovian regimes. Specifically, we explore the dynamic behavior of the entropic uncertainty relation for a pair of incompatible observables under the reservoir-induced atomic decay effect both with and without quantum memory. We find that the uncertainty dramatically depends on both the atom-cavity and the cavity-reservoir interactions, as well as the correlation time, $τ$, of the structured reservoir. Furthermore, we verify that the uncertainty is anti-correlated with the purity of the state of the observed qubit-system. We also propose a remarkably simple and efficient way to reduce the uncertainty by utilizing quantum weak measurement reversal. Therefore our work offers a new insight into the uncertainty dynamics for multi-component measurements within an open system, and is thus important for quantum precision measurements.

quant-ph↗

arXiv2015

Generalized Remote Preparation of Arbitrary $m$-qubit Entangled States via Genuine Entanglements

Herein, we present a feasible, general protocol for quantum communication within a network via generalized remote preparation of an arbitrary $m$-qubit entangled state designed with genuine tripartite Greenberger--Horne--Zeilinger-type entangled resources. During the implementations, we construct novel collective unitary operations; these operations are tasked with performing the necessary phase transfers during remote state preparations. We have distilled our implementation methods into a five-step procedure, which can be used to faithfully recover the desired state during transfer. Compared to previous existing schemes, our methodology features a greatly increased success probability. After the consumption of auxiliary qubits and the performance of collective unitary operations, the probability of successful state transfer is increased four-fold and eight-fold for arbitrary two- and three-qubit entanglements when compared to other methods within the literature, respectively. We conclude this paper with a discussion of the presented scheme for state preparation, including: success probabilities, reducibility and generalizability.

quant-ph↗

arXiv2015

Neuroreceptor Activation by Vibration-Assisted Tunneling

G protein-coupled receptors (GPCRs) constitute a large family of receptor proteins that sense molecular signals on the exterior of a cell and activate signal transduction pathways within the cell. Modeling how an agonist activates such a receptor is fundamental for an understanding of a wide variety of physiological processes and it is of tremendous value for pharmacology and drug design. Inelastic electron tunneling spectroscopy (IETS) has been proposed as a model for the mechanism by which olfactory GPCRs are activated by a bound agonist. We apply this hypothesis to GPCRs within the mammalian nervous system using quantum chemical modeling. We found that non-endogenous agonists of the serotonin receptor share a particular IET spectral aspect both amongst each other and with the serotonin molecule: a peak whose intensity scales with the known agonist potencies. We propose an experiential validation of this model by utilizing lysergic acid dimethylamide (DAM-57), an ergot derivative, and its deuterated isotopologues; we also provide theoretical predictions for comparison to experiment. If validated our theory may provide new avenues for guided drug design and elevate methods of in silico potency/activity prediction.

physics.bio-ph↗

arXiv2011

Dimensional Scaling Treatment with Relativistic Corrections for Stable Multiply Charged Atomic Ions in High-Frequency Super-Intense Laser Fields

We present a theoretical framework which describes multiply-charged atomic ions, their stability within super-intense laser fields,also lay corrections to the systems due to relativistic effects. Dimensional scaling calculations with relativistic corrections for systems: H, H$^{-}$, H$^{2-}$, He, He$^{-}$, He$^{2-}$, He$^{3-}$ within super-intense laser fields were completed. Also completed were three-dimensional self consistent field calculations to verify the dimensionally scaled quantities. With the aforementioned methods the system's ability to stably bind 'additional' electrons through the development of multiple isolated regions of high potential energy leading to nodes of high electron density is shown. These nodes are spaced far enough from each other to minimized the electronic repulsion of the electrons, while still providing adequate enough attraction so as to bind the excess elections into orbitals. We have found that even with relativistic considerations these species are stably bound within the field. It was also found that performing the dimensional scaling calculations for systems within the confines of laser fields to be a much simpler and more cost-effective method than the supporting D=3 SCF method. The dimensional scaling method is general and can be extended to include relativistic corrections to describe the stability of simple molecular systems in super-intense laser fields.

quant-ph↗