Atomic mirror

Last updated

In physics, an atomic mirror is a device which reflects neutral atoms in a way similar to the way a conventional mirror reflects visible light. Atomic mirrors can be made of electric fields or magnetic fields, [1] electromagnetic waves [2] or just silicon wafer; in the last case, atoms are reflected by the attracting tails of the van der Waals attraction (see quantum reflection). [3] [4] [5] Such reflection is efficient when the normal component of the wavenumber of the atoms is small or comparable to the effective depth of the attraction potential (roughly, the distance at which the potential becomes comparable to the kinetic energy of the atom). To reduce the normal component, most atomic mirrors are blazed at the grazing incidence.

Contents

Ridged mirror. The wave with wavevector
K
-
{\displaystyle ~{\vec {K}}~}
is scattered at ridges separated by distance
L
{\displaystyle ~L~} Image-Ridged Mirror figureB.png
Ridged mirror. The wave with wavevector is scattered at ridges separated by distance

At grazing incidence, the efficiency of the quantum reflection can be enhanced by a surface covered with ridges (ridged mirror). [6] [7] [8] [9]

The set of narrow ridges reduces the van der Waals attraction of atoms to the surfaces and enhances the reflection. Each ridge blocks part of the wavefront, causing Fresnel diffraction. [8]

Such a mirror can be interpreted in terms of the Zeno effect. [7] We may assume that the atom is "absorbed" or "measured" at the ridges. Frequent measuring (narrowly spaced ridges) suppresses the transition of the particle to the half-space with absorbers, causing specular reflection. At large separation between thin ridges, the reflectivity of the ridged mirror is determined by dimensionless momentum , and does not depend on the origin of the wave; therefore, it is suitable for reflection of atoms.

Applications

See also

Related Research Articles

<span class="mw-page-title-main">Casimir effect</span> Force resulting from the quantisation of a field

In quantum field theory, the Casimir effect is a physical force acting on the macroscopic boundaries of a confined space which arises from the quantum fluctuations of a field. It is named after the Dutch physicist Hendrik Casimir, who predicted the effect for electromagnetic systems in 1948.

<span class="mw-page-title-main">Quantum Zeno effect</span> Quantum measurement phenomenon

The quantum Zeno effect is a feature of quantum-mechanical systems allowing a particle's time evolution to be slowed down by measuring it frequently enough with respect to some chosen measurement setting.

Stochastic electrodynamics (SED) is a variant of classical electrodynamics (CED) of theoretical physics. SED consists of a set of controversial theories that posit the existence of a classical Lorentz invariant radiation field having statistical properties similar to that of the electromagnetic zero-point field (ZPF) of quantum electrodynamics (QED).

An atom interferometer is an interferometer which uses the wave character of atoms. Similar to optical interferometers, atom interferometers measure the difference in phase between atomic matter waves along different paths. Atom interferometers have many uses in fundamental physics including measurements of the gravitational constant, the fine-structure constant, the universality of free fall, and have been proposed as a method to detect gravitational waves. They also have applied uses as accelerometers, rotation sensors, and gravity gradiometers.

An atom laser is a coherent state of propagating atoms. They are created out of a Bose–Einstein condensate of atoms that are output coupled using various techniques. Much like an optical laser, an atom laser is a coherent beam that behaves like a wave. There has been some argument that the term "atom laser" is misleading. Indeed, "laser" stands for light amplification by stimulated emission of radiation which is not particularly related to the physical object called an atom laser, and perhaps describes more accurately the Bose–Einstein condensate (BEC). The terminology most widely used in the community today is to distinguish between the BEC, typically obtained by evaporation in a conservative trap, from the atom laser itself, which is a propagating atomic wave obtained by extraction from a previously realized BEC. Some ongoing experimental research tries to obtain directly an atom laser from a "hot" beam of atoms without making a trapped BEC first.

In atomic physics, a ridged mirror is a kind of atomic mirror, designed for the specular reflection of neutral particles (atoms) coming at a grazing incidence angle. In order to reduce the mean attraction of particles to the surface and increase the reflectivity, this surface has narrow ridges.

Quantum reflection is a uniquely quantum phenomenon in which an object, such as a neutron or a small molecule, reflects smoothly and in a wavelike fashion from a much larger surface, such as a pool of mercury. A classically behaving neutron or molecule will strike the same surface much like a thrown ball, hitting only at one atomic-scale location where it is either absorbed or scattered. Quantum reflection provides a powerful experimental demonstration of particle-wave duality, since it is the extended quantum wave packet of the particle, rather than the particle itself, that reflects from the larger surface. It is similar to reflection high-energy electron diffraction, where electrons reflect and diffraction from surfaces, and grazing incidence atom scattering, where the fact that atoms can also be waves is used to diffract from surfaces.

Atom optics "refers to techniques to manipulate the trajectories and exploit the wave properties of neutral atoms". Typical experiments employ beams of cold, slowly moving neutral atoms, as a special case of a particle beam. Like an optical beam, the atomic beam may exhibit diffraction and interference, and can be focused with a Fresnel zone plate or a concave atomic mirror.

The Institute for Laser Science is a department of the University of Electro Communications, located near Tokyo, Japan.

Interferometric microscopy or imaging interferometric microscopy is the concept of microscopy which is related to holography, synthetic-aperture imaging, and off-axis-dark-field illumination techniques. Interferometric microscopy allows enhancement of resolution of optical microscopy due to interferometric (holographic) registration of several partial images and the numerical combining.

Within quantum technology, a quantum sensor utilizes properties of quantum mechanics, such as quantum entanglement, quantum interference, and quantum state squeezing, which have optimized precision and beat current limits in sensor technology. The field of quantum sensing deals with the design and engineering of quantum sources and quantum measurements that are able to beat the performance of any classical strategy in a number of technological applications. This can be done with photonic systems or solid state systems.

<span class="mw-page-title-main">Trojan wave packet</span> Wave packet that is nonstationary and nonspreading

A trojan wave packet is a wave packet that is nonstationary and nonspreading. It is part of an artificially created system that consists of a nucleus and one or more electron wave packets, and that is highly excited under a continuous electromagnetic field. Its discovery as one of significant contributions to the Quantum Theory was awarded the 2022 Wigner Medal for Iwo Bialynicki-Birula

Double ionization is a process of formation of doubly charged ions when laser radiation is exerted on neutral atoms or molecules. Double ionization is usually less probable than single-electron ionization. Two types of double ionization are distinguished: sequential and non-sequential.

<span class="mw-page-title-main">Hydrodynamic quantum analogs</span> Similar behavior of quantum systems to droplets bouncing on a fluid

In physics, the hydrodynamic quantum analogs refer to experimentally-observed phenomena involving bouncing fluid droplets over a vibrating fluid bath that behave analogously to several quantum-mechanical systems.

Quantum microscopy allows microscopic properties of matter and quantum particles to be measured and imaged. Various types of microscopy use quantum principles. The first microscope to do so was the scanning tunneling microscope, which paved the way for development of the photoionization microscope and the quantum entanglement microscope.

<span class="mw-page-title-main">Peter E. Toschek</span> German physicist (1933–2020)

Peter E. Toschek was a German experimental physicist who researched nuclear physics, quantum optics, and laser physics. He is known as a pioneer of laser spectroscopy and for the first demonstration of single trapped atoms (ions). He was a professor at Hamburg University.

Harald Friedrich was a German physicist specializing in theoretical atomic physics.

Spin squeezing is a quantum process that decreases the variance of one of the angular momentum components in an ensemble of particles with a spin. The quantum states obtained are called spin squeezed states. Such states have been proposed for quantum metrology, to allow a better precision for estimating a rotation angle than classical interferometers. Recently, it was shown that these states cannot provide a better precision.

<span class="mw-page-title-main">Crispin Gardiner</span> New Zealand physicist

Crispin William Gardiner is a New Zealand physicist, who has worked in the fields of quantum optics, ultracold atoms and stochastic processes. He has written about 120 journal articles and several books in the fields of quantum optics, stochastic processes and ultracold atoms

<span class="mw-page-title-main">Carlos Stroud</span> American physicist

Carlos Ray Stroud, Jr. is an American physicist and an educator. Working in the field of quantum optics, Stroud has carried out theoretical and experimental studies in most areas of the field from its beginnings in the late 1960s, studying the fundamentals of the quantum mechanics of atoms and light and their interaction. He has authored over 140 peer-reviewed papers and edited seven books. He is a fellow of the American Physical Society and the Optical Society of America, as well as a Distinguished Traveling Lecturer of the Division of Laser Science of the American Physical Society. In this latter position he travels to smaller colleges giving colloquia and public lectures.

References

  1. H. Merimeche (2006). "Atomic beam focusing with a curved magnetic mirror". Journal of Physics B . 39 (18): 3723–3731. Bibcode:2006JPhB...39.3723M. doi:10.1088/0953-4075/39/18/002. S2CID   121851648.
  2. V. I. Balykin & V. S. Letokhov (1988). "Quantum-State-Selective Mirror Reflection of Atoms by Laser Light". Physical Review Letters . 60 (21): 2137–2140. Bibcode:1988PhRvL..60.2137B. doi:10.1103/PhysRevLett.60.2137. PMID   10038269.
  3. H. Friedrich; G. Jacoby, C. G. Meister (2002). "quantum reflection by Casimir–van der Waals potential tails". Physical Review A . 65 (3): 032902. Bibcode:2002PhRvA..65c2902F. doi:10.1103/PhysRevA.65.032902.
  4. F. Shimizu (2001). "Specular Reflection of Very Slow Metastable Neon Atoms from a Solid Surface". Physical Review Letters . 86 (6): 987–990. Bibcode:2001PhRvL..86..987S. doi:10.1103/PhysRevLett.86.987. PMID   11177991. S2CID   34195829.
  5. H. Oberst; Y. Tashiro; K. Shimizu; F. Shimizu (2005). "Quantum reflection of He* on silicon". Physical Review A . 71 (5): 052901. Bibcode:2005PhRvA..71e2901O. doi:10.1103/PhysRevA.71.052901.
  6. F. Shimizu; J. Fujita (2002). "Giant Quantum Reflection of Neon Atoms from a Ridged Silicon Surface". Journal of the Physical Society of Japan . 71 (1): 5–8. arXiv: physics/0111115 . Bibcode:2002JPSJ...71....5S. doi:10.1143/JPSJ.71.5. S2CID   19013515.
  7. 1 2 D. Kouznetsov; H. Oberst (2005). "Reflection of Waves from a Ridged Surface and the Zeno Effect". Optical Review . 12 (5): 1605–1623. Bibcode:2005OptRv..12..363K. doi:10.1007/s10043-005-0363-9. S2CID   55565166.
  8. 1 2 H. Oberst; D. Kouznetsov; K. Shimizu; J. Fujita; F. Shimizu (2005). "Fresnel Diffraction Mirror for an Atomic Wave" (PDF). Physical Review Letters . 94 (1): 013203. Bibcode:2005PhRvL..94a3203O. doi:10.1103/PhysRevLett.94.013203. hdl: 2241/104208 . PMID   15698079.
  9. D. Kouznetsov; H. Oberst (2005). "Scattering of waves at ridged mirrors" (PDF). Physical Review A . 72 (1): 013617. Bibcode:2005PhRvA..72a3617K. doi:10.1103/PhysRevA.72.013617.[ permanent dead link ]