Double-slit Research Articles

Fabrication of Plasmonic Optical Nanoslit Pore Device for Single Molecule Analysis

About 60 years ago, the biological cell counter with an electrical detection technique was invented by Dr. Coulter. The solid state nanopores can be fabricated by using various techniques such as ion sculpting, high energy electron beams such as such as field emission scanning microscopy (FESEM) and transmission electron microscopy (TEM). However, this fabricated portable nanopore device is reported to have too high error rates. The high error rates may be attributed to the electrical double layer formed in the nanopore channel. Considering the fact that most biosensors are utilizing the optical detection technique, the optical pore device can be an excellent candidate for the next generation single molecule sensor. we have also fabricated the nanopore with its diameter ranging from 10 to 3 nm inside the FIB drilled aperture by using various surface treatments including electron beam irradiations and ion beam irradiation. In this report, we will address the fabrication of the optical pores with double slits. We observed the nanoscale Young’s interference from the double slits dependent upon the pitch. With increasing the pitch size, the periodic interference phenomena are observed and the optical intensity through the nanoscale slits are also periodically increasing We also fabricated the (7 x 7) hole array with its diameter of ~ 200 nm dependent upon the pitch between the holes with and without the nano- scale double slits. The highest enhancement of 1.72 at the peak is observed at 530 nm pitch without slits, and enhancement of 8.36 at the peak is also observed from the (7 x 7) hole array with a 530 nm pitch with nanoscale double slits. The enhancement of ~ 4-fold increase at the peak can be attributed to the constructive interference between two surface plasmon waves from hole and slits. This device can be utilized as optical manipulation and characterization for nanobio sensor, especially for single molecule analysis Figure 1

Two Crucial Experiments on the Nature of Light: Beyond the Bounds of Wave-Particle Duality

The wave-particle duality of light has been hanging over the clouds of science as an insuperable mystery. Debates have gone on for centuries as to which of the two aspects of light best represents the natural property of light. On the one hand, the particle theory of light camp made its own submissions a long time ago with many experimental demonstrations to confirm its position. On the other hand, the wave theory of light camp did organize or face some experiments to corroborate its own position. But then, a middle ground interpretation was shoveled-in by Niels Bohr during the second decade of the 20th Century. For him, the two aspects of light are complementary and Louis de Broglie popularized it, despite the halting beginnings of the complementarity Thesis. A double-slit experiment was, however, organized to show that light has these dual aspects. The central thesis of this paper is that though light exhibits these dual aspects, it is fundamentally a wave. The paper adopts the historiographical approach in navigating this lingering issue of the nature of light in the history of science.

Young's Double-Slit Interference in a Hydrogen Atom.

We demonstrate the possibility of realizing Young's double-slit interference in a hydrogen atom via abinitio simulations. By exposing the hydrogen atom to a high-frequency intensive laser pulse, the bound state distorts into a dichotomic Kramers-Henneberger state whose photoelectron momentum distribution imprints a double-slit interference structure. The dichotomic hydrogen atom presents molecular peculiarities, such as charge-resonance enhanced ionization, electron spin flipping due to the non-Abelian Berry phase. In return, the photoelectron momentum distribution carrying the double-slit interference structure provides unambiguous evidence on the existence of Kramers-Henneberger states, and thus the adiabatic stabilization.

Exploring the Phenomena of a Quantum Eraser in Young’s Double Slit Experiment

This experiment explores the quantum phenomenon known as the Quantum Eraser, using a variation of Young’s Double Slit experiment. Young’s Double Slit experiment demonstrates that light acts as a wave by creating an interference pattern when diffracted through two slits. If one measures which of the two slits the photons pass through, then the interference pattern is replaced by a single bright spot, as would be expected for particle-like behaviour. The “Quantum Eraser” eliminates the measurement on the photons, thereby reintroducing the interference pattern observed in Young’s original experiment. The experiment’s first stage saw Young’s Double Slit experiment recreated and an interference pattern was observed. Upon adding two orthogonally polarized filters, the photon’s path was measured, and the interference pattern was removed. By then adding a third filter which was polarized 45O relative to both other polarisers, the interference pattern was somewhat restored. For each experiment, the heights of the peaks in the interference patterns were compared to each other to examine the quality of the reproduced interference pattern based on the original double slit interference pattern. This comparison gave a quantitative result that demonstrated that the Quantum Eraser was able to restore the interference pattern to within 5 standard errors, thereby exemplifying the effect that changing the measurement conditions affects the final measurement.

Measurement of the horizontal beam emittance ofundulator radiation by tandem-double-slit opticalsystem.

A tandem-double-slit optical system was constructed to evaluate the practical beam emittance of undulator radiation. The optical system was a combination of an upstream slit (S1) and downstream slit (S2) aligned on the optical axis with an appropriate separation. The intensity distribution after the double slits, I(x1, x2), was measured by scanning S1 and S2 in the horizontal direction. Coordinates having 1/\sqrt e intensity were extracted from I(x1, x2), whose contour provided the standard deviation ellipse in the x1-x2 space. I(x1, x2) was converted to the corresponding distribution in the phase space, I(x1, x1'). The horizontal beam emittance was evaluated to be 3.1 nm rad, which was larger than the value of 2.4 nm rad estimated by using ray-tracing. It was found that the increase was mainly due to an increase in beam divergence rather than size.

Commentary: False-Positive Effect in the Radin Double-Slit Experiment on Observer Consciousness as Determined With the Advanced Meta-Experimental Protocol.

Commentary: False-Positive Effect in the Radin Double-Slit Experiment on Observer Consciousness as Determined With the Advanced Meta-Experimental Protocol.

A Tiny, Counterintuitive Change to the Mathematics of the Schrodinger Wave Packet and Quantum ElectroDynamics Could Vastly Simplify How We View Nature


 
 
 This article proposes that an unexpected approach to the mathematics of a Schro ̋dinger wave packet and Quantum Electro-Dynamics (QED), could vastly simplify how we perceive the world around us. It could get rid of most if not all quantum weirdness. Schro ̋dinger’s cat would be gone. Even things that we thought were unquestionably true about the quantum world would change. For example, the double slit experiment would no longer support wave particle duality. Experiments that appeared to say that entangled particles can communicate instantaneously over great distances, would no longer say that. Although the tiny mathematical change is counterintuitive, Occam’s razor dictates that we consider it because it simplifies how we view Nature in such a pervasive way. The change in question is to view a Schro ̋dinger wave packet as part of a larger Elementary Wave traveling in the opposite direction. It is known in quantum mechanics that the same wave can travel in two countervailing directions simultaneously. Equivalent changes would be made to QED and Quantum Field Theory. It is known in QM that there are zero energy waves: for example, the Schro ̋dinger wave carries amplitudes but not energy.
 
 

Bohmian Mechanics: Realism and the “Box” Experiment

It is difficult to articulate how we should take a realist attitude towards Bohmian mechanics because there are many versions of it. This paper aims to clarify the realist commitments of Bohmian mechanics and how we can understand it from a general scientific realist perspective. I use the box experiment, a double-slit like experiment conducted by Cardone et al. (Phys Lett A 326(1–2):1–13, 2004; Int J Mod Phys B 20(09):1107–1121, 2006), as a working example to argue that a causal realist account (in the sense of selective realism) that is applicable to Bohmian mechanics, has to be supplemented with the use of Inference to the Best Explanation. The reason is because causal realism on its own does not form a sufficient basis for realism about Bohmian mechanics. In particular, I argue that the existence of the pilot wave explains why we observe an anomalous interference effect in the experiment of Cardone et al. The conclusion to draw is that a complete realist account about Bohmian mechanics rests on explanatory considerations.

Dose profiles and x-ray energy optimization for microbeam radiation therapy by high-dose, high resolution dosimetry using Sm-doped fluoroaluminate glass plates and Monte Carlo transport simulation

Microbeam radiation therapy (MRT) utilizes highly collimated synchrotron generated x-rays to create narrow planes of high dose radiation for the treatment of tumors. Individual microbeams have a typical width of 30–50 µm and are separated by a distance of 200–500 µm. The dose delivered at the center of the beam is lethal to cells in the microbeam path, on the order of hundreds of Grays (Gy). The tissue between each microbeam is spared and helps aid in the repair of adjacent damaged tissue. Radiation interactions within the peak of the microbeam, such as the photoelectric effect and incoherent (atomic Compton) scattering, cause some dose to be delivered to the valley areas adjacent to the microbeams. As the incident x-ray energy is modified, radiation interactions within a material change and affect the probability of interactions, as well as the directionality and energy of ionizing particles (electrons) that deposit energy in the valley regions surrounding the microbeam peaks. It is crucial that the valley dose between microbeams be minimal to maintain the effectiveness of MRT. Using a monochromatic x-ray source with x-ray energies ranging from 30 to 150 keV, a detailed investigation into the effect of incident x-ray energy on the dose profiles of microbeams was performed using samarium doped fluoroaluminate (FA) glass as the medium. All dosimetric measurements were carried out using a purpose-built fluorescence confocal microscope dosimetric technique that used Sm-doped FA glass plates as the irradiated medium. Dose profiles are measured over a very a wide range of x-ray energies at micrometer resolution and dose distribution in the microbeam are mapped. The measured microbeam profiles at different energies are compared with the MCNP6 radiation transport code, a general transport code which can calculate the energy deposition of electrons as they pass through a given material. The experimentally measured distributions can be used to validate the results for electron energy deposition in fluoroaluminate glass. Code validation is necessary for using transport codes in future treatment planning for MRT and other radiation therapies. It is shown that simulated and measured micro beam-profiles are in good agreement, and micrometer level changes can be observed using this high-resolution dosimetry technique. Full width at 10% of the maximum peak (FW@10%) was used to quantify the microbeam width. Experimental measurements on FA glasses and simulations on the dependence of the FW@10% at various energies are in good agreement. Simulations on energy deposited in water indicate that FW@10% reaches a local minimum around energies 140 keV. In addition, variable slit width experiments were carried out at an incident x-ray energy of 100 keV in order to determine the effect of the narrowing slit width on the delivered peak dose. The microbeam width affects the peak dose, which decreases with the width of the microbeam. Experiments suggest that a typical microbeam width for MRT is likely to be between 20–50 µm based on this work.

Zero-point energy and photon spin-induced diffraction phenomena

A brief review of our previously introduced forward and backward in time formalism for non-relativistic electron diffraction and its relativistic extension to study photons in time and space is presented. The zero-point energy in the Planck black body spectrum emerges naturally once time-symmetric motion — inherent in Maxwell equations — is invoked for photons. A study of two-slit experiments for slits smaller than the wavelength of the photon unravels novel phenomena due to the spin of the photon. Our proposed experiments are within reach of present technology and could be of interest for modern imaging and quantum optics.

Pre-Service Teachers’ Declarative Knowledge of Wave-Particle Dualism of Electrons and Photons: Finding Lexicons by Using Network Analysis

Learning the wave-particle dualism of electrons and photons plays a central role in understanding quantum physics. Teaching it requires that the teacher is fluent in using abstract and uncommon terms. We inspect the lexical structures of pre-service teachers’ declarative knowledge about the wave-particle dualism of electrons and photons in the context of double-slit interference. The declarative knowledge is analyzed in the form of a lexical network of terms. We focus on lexical structures because, in teaching and learning, knowledge is communicated mostly through lexical structures, i.e., by speaking and writing. Using the lexical networks, we construct the lexicons used by pre-service teachers to express their knowledge of electrons and photons in the context of double-slit interference. The lexicons consist of eight different key terms, each representing a set of closely-related or synonymous terms. The lexicons by 14 pre-service teachers reveal remarkable variation and differences, and are strongly context-dependent. We also analyzed lexicons corresponding to two didactically-oriented research articles on the same topic and found that they also differ. Lexicons paralleling both texts are found among the pre-service teachers’ lexicons. However, only some of the pre-service teachers use such rich vocabulary as would indicate multi-faceted understanding of quantum entities.

System Theory, Proton Stability, Double-Slit Experiment, and Cyclotron Physics

Every system is composed of constitutional elements that are stable. Unstable elements cannot build a system. The hydrogen atom, for example, is the system composed out of two stable elements: proton and electron. How proton could be a system made out of unstable elements as quarks and gluons is an unanswered question that particle physics need to face in order to strengthen its theoretical basis. System Theory offers an original interpretation of double-slit experiment and requires re-examination of cyclotron physics.

Double-slit effect on laser induced electron diffraction of dimers

We theoretically study strong-field ionization of dimers with large internuclear distance in linearly and circularly polarized light fields. By numerically solving the time-dependent Schrödinger equation (TDSE), we show that the double-slit interference effect plays a significant role in the laser-induced electron diffraction of dimers. And the prominent double-slit interference structures are sensitive to the symmetry and orientation of the orbitals of dimers. We then develop a semi-classical trajectory model including the double-slit effect by coherently summing up the contributions of two separated atoms. This model explains the interference fringes of TDSE simulations. And the effect of long-range potential on the double-slit interference is discussed. This work provides intuitive physical insights into how dimers being ionized in strong laser fields and has implications to extract ultrafast dynamics of polyatomic molecules from strong-field photoelectron spectroscopy.

Double Ring Stand Interference

Double-slit interference is a difficult phenomenon for students to grasp in an introductory physics course. A thorough understanding of constructive and destructive interference is critical, but even with such an understanding, visualizing exactly how an interference pattern is formed by light passing through two slits can still be a challenge for students. Here, we describe a simple demonstration that seems to have improved our students’ understanding of this phenomenon. The required materials are readily available in nearly any physics classroom or lab, and the demonstration can easily be constructed in 5 to 10 minutes.

Q & A

The double-slit experiment has long been the cornerstone of quantum physics. Now Urbasi Sinha's triple-slit variant could usher in an era of higher-dimensional quantum computing

An experimental test of the geodesic rule proposition for the noncyclic geometric phase.

The geometric phase due to the evolution of the Hamiltonian is a central concept in quantum physics and may become advantageous for quantum technology. In noncyclic evolutions, a proposition relates the geometric phase to the area bounded by the phase-space trajectory and the shortest geodesic connecting its end points. The experimental demonstration of this geodesic rule proposition in different systems is of great interest, especially due to the potential use in quantum technology. Here, we report a previously unshown experimental confirmation of the geodesic rule for a noncyclic geometric phase by means of a spatial SU(2) matter-wave interferometer, demonstrating, with high precision, the predicted phase sign change and π jumps. We show the connection between our results and the Pancharatnam phase. Last, we point out that the geodesic rule may be applied to obtain the red shift in general relativity, enabling a new quantum tool to measure gravity.

2단 슬릿 댐퍼형 에너지 흡수장치를 가지는 대형 H형 보-기둥 접합부에 관한 해석적 연구

2단 슬릿 댐퍼형 에너지 흡수장치를 가지는 대형 H형 보-기둥 접합부에 관한 해석적 연구

Wave-particle duality employing quantum coherence in superposition with non-orthogonal pointers

We propose the notion of quantum coherence for superpositions over states which are not necessarily mutually orthogonal. This anticipatedly leads to a resource theory of non-orthogonal coherence. We characterize free states and free operations in this theory, and connect the latter with free operations in the resource theory of quantum coherence for orthogonal bases. We show that the concept of non-orthogonal coherence naturally furnishes us with a wave-particle duality in quantum double-slit experiments where the channels beyond the slits are leaky between them. Furthermore, we demonstrate existence of a unique maximally coherent qubit state corresponding to any given purity. In addition, and in contradistinction with the case of orthogonal bases, there appears a non-trivial minimally coherent qubit state for a given purity. We also study the behavior of quantum coherence for some typical configurations of non-orthogonal bases which have no analogs for orthogonal bases. We further investigate the problem of determining the energy cost of creating non-orthogonal coherence, and find that it scales linearly with the non-orthogonal coherence created.

Towards the ultrafast optical nanopore platform for single molecule sensing

Abstract Recently there have been significant interests about fabrication of optical nanopore with its diameter range of 5 nm–10 nm for single molecule analysis and manipulation. However, due to very small amount of the optical intensity through the tiny size of the nano-aperture much smaller than the optical wavelength, the optical intensity enhancement via plasmonic effect by using pore array or periodic groove patterns have been tried. Also, the double slits with nanoscale width are reported to provide the constructive periodic modulation for the transverse-magnetic (TM) wave mode. In this report, the Au aperture arrays sidelined with the nanoscale double slit, and surrounded by 4 nanoscale slits have been fabricated with optical characterization in the visible range.

Double slits with single atoms

Thomas Young’s double-slit experiment is famous for demonstrating the principle of interference. Andrew Murray explains why it’s now possible to carry out an equivalent experiment using lasers that have excited individual rubidium atoms