I. Loris, R. Sasaki
Simple theorems relating a quantum mechanical system to the corresponding classical one at equilibrium and connecting the quantum eigenvalues to the frequencies of normal modes oscillations are presented. Corresponding to each quantum eigenfunction, a ` classical eigenfunction' is associated. Those belonging to `elementary excitations' play an important role.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
继续探索
We propose a natural expansion of the atomic field operator in studying elementary excitations in trapped Bose-Einstein Condensation (BEC) system near T=0K. Based on this expansion, a system of coupled equations for elementary excitations, which is equivalent to the standard linearized GP equation, is given to describe the collective excitation of BEC in a natual way. Applications of the new formalism to the homogeneous case emphasize on the zero mode and its relevant ground state of BEC.
We introduce an analytical solution to the one of the most familiar problems from the elementary quantum mechanics textbooks. The following discussion provides simple illustrations to a number of general concepts of quantum chaology, along with some recent developments in the field and a historical perspective on the subject.
When a single quantum of electromagnetic field excitation is added to the same spatio-temporal mode of a coherent state, a new field state is generated that exhibits intermediate properties between those of the two parents. Such a single-photon-added coherent state is obtained by the action of the photon creation operator on a coherent state and can thus be regarded as the result of the most elementary excitation process of a classical light field. Here we present and describe in depth the experimental realization of such states and their complete analysis by means of a novel ultrafast, time-d…
Quantum Dynamics and Elementary Excitations in Superfluid He4 Films at Low Temperatures
本文提出描述低温超流He4薄膜的量子非线性薛定谔方程，导出声子-旋子色散关系，并解析及数值求解出孤子与周期波解，具有重要应用前景。
Based on the theory of submicroscopic quantum mechanics recently constructed by the author the mass of elementary spatial excitations called inertons, which accompany a moving particle, is estimated herein. These excitations are treated as carriers of both inertial and gravitational properties of the particle.
In quantum theory, symmetry has to be defined necessarily in terms of the family of unit rays, the state space. The theorem of Wigner asserts that a symmetry so defined at the level of rays can always be lifted into a linear unitary or an antilinear antiunitary operator acting on the underlying Hilbert space. We present a proof of this theorem which is both elementary and economical. Central to our proof is the recognition that a given Wigner symmetry can, by post-multiplication by a unitary symmetry, be taken into either the identity or complex conjugation. Our analysis involves a judicious i…
Studies of quantum fields and gravity suggest the existence of a minimal length, such as Planck length \cite{Floratos,Kempf}. It is natural to ask how the existence of a minimal length may modify the results in elementary quantum mechanics (QM) problems familiar to us \cite{Gasiorowicz}. In this paper we address a simple problem from elementary non-relativistic quantum mechanics, called "particle in a box", where the usual continuum (1+1)-space-time is supplanted by a space-time lattice. Our lattice consists of a grid of $λ_0 \times τ_0 $ rectangles, where $λ_0$, the lattice parameter, is a fu…
We report the experimental demonstration of optomechanical light storage in a silica resonator. We use writing and readout laser pulses tuned to one mechanical frequency below an optical cavity resonance to control the coupling between the mechanical displacement and the optical field at the cavity resonance. The writing pulse maps a signal pulse at the cavity resonance to a mechanical excitation. The readout pulse later converts the mechanical excitation back to an optical pulse. The light storage lifetime is determined by the relatively long damping time of the mechanical excitation.
A mixture of two species of pseudospin-1/2 Bose gases exhibits interesting interplay between spin and orbital degrees of freedom. Expectation values of various quantities of the collective spins of the two species play crucial roles in the Gross-Pitaevskii-like equations governing the four orbital wave functions in which Bose-Einstein condensation occurs. Consequently, the elementary excitations of these orbital wave functions reflect properties of the collective spins. When the coupling between the two collective spins is isotropic, the energy gap of the gapped orbital excitation peaks, while…
A physical model of the fluctuating vacuum (FlcVcm) and the photon as an elementary collective excitation in a solitary needle cylindrical form are offered. We assume that the FlcVcm is consistent by neutral dynamides, which are streamlined in a close-packed crystalline lattice. Every dynamide is a neutral pair, consistent by massless opposite point-like elementary electric charges (ElmElcChrgs): electrino (-) and positrino (+). In an equilibrium position two contrary Pnt-Lk ElmElcChrgs within every one dynamide are very closely installed one to another and therefore its aggregate polarization…
Landau's theory of Fermi liquids is generalized by incorporating the de Broglie waves diffraction. A newly derived kinetic equation of the Fermi particles is used to derive a general dispersion relation and the excitation of zero sound is studied. A new mode is found due to the quantum correction. It is shown that the zero sound can exist even in an ideal Fermi gas. We also disclose a new branch of frequency spectrum due to the weak interaction.
Spectroscopic signatures of emergent elementary excitations in a kinetically constrained long-range interacting two-dimensional spin system
研究二维Rydberg晶格气体中动能约束自旋系统中涌现的基本激发的光谱特征，通过侧带光谱学实验探测其性质。
We develop variational matrix product state (MPS) methods with symmetries to determine dispersion relations of one dimensional quantum lattices as a function of momentum and preset quantum number. We test our methods on the XXZ spin chain, the Hubbard model and a non-integrable extended Hubbard model, and determine the excitation spectra with a precision similar to the one of the ground state. The formulation in terms of quantum numbers makes the topological nature of spinons and holons very explicit. In addition, the method also enables an easy and efficient direct calculation of the necessar…
Combining topologically-protected chiral light transport and laser amplification gives rise to topological lasers, whose operation is immune to fabrication imperfections and defects, uncovering the role of topology in a novel nonlinear non-Hermitian regime. We study a topological laser based on the photonic Haldane model with selective pumping of chiral edge modes described by saturable gain. We investigate elementary excitations around the mean-field steady state and their consequences for the coherence properties. In particular, we show that the hybridization of chiral edge modes gives rise …
Spectroscopy of elementary excitations from quench dynamics in a dipolar XY Rydberg simulator
通过极化XY稀释气体模拟器展示淬火光谱法，研究多体系统低能激发特性，揭示铁磁与反铁磁耦合下激发谱差异及长程相互作用影响。
This paper suggests a new way to compute the path integral for simple quantum mechanical systems. The new algorithm originated from previous research in string theory. However, its essential simplicity is best illustrated in the case of a free non relativistic particle, discussed here, and can be appreciated by most students taking an introductory course in Quantum Mechanics. Indeed, the emphasis is on the role played by the {\it entire family of classical trajectories} in terms of which the path integral is computed exactly using a functional representation of the Dirac delta-distribution. We…
Motivated by the rich phase diagrams recently unveiled in frustrated spin-1 chains with competing next-nearest neighbour and four-spin interactions, we investigate the nature of the elementary excitations of spin-1 chains in the vicinity of phase transitions using the matrix-product state (MPS) representation of elementary excitations. First, we show that both spinons and magnons naturally arise in SU(2) invariant spin chains when describing ground states and elementary excitations using MPS. Then we investigate the nature of the elementary excitations across the first-oder transition between …
An elementary proof of symmetrization postulate in quantum mechanics for a system of particles
本文通过数学方法证明了量子力学中粒子系统对称化公理的初等性，揭示了波函数在特定条件下必须完全对称或反对称的结论。
Complex techniques of general relativity are used to determine \emph{all} the states in the two and three dimensional momentum spaces in which the equality holds in the uncertainty relations for the non-commuting basic observables of Euclidean invariant elementary quantum mechanical systems, even with non-zero intrinsic spin. It is shown that while there is a 1-parameter family of such states for any two components of the angular momentum vector operator with any angle between them, such states exist for a component of the linear and angular momenta \emph{only if} these components are orthogon…
Every system in physics is described in terms of interacting elementary particles characterized by modulated spacetime recurrences. These intrinsic periodicities, implicit in undulatory mechanics, imply that every free particle is a reference clock linking time to the particle's mass, and every system is formalizable by means of modulated elementary spacetime cycles. We propose a novel consistent relativistic formalism based on intrinsically cyclic spacetime dimensions, encoding the quantum recurrences of elementary particles into spacetime geometrodynamics. The advantage of the resulting theo…
Mechanical photoluminescence excitation spectra of a strongly driven spin-mechanical system
实验研究了NV中心与金刚石悬臂耦合的自旋-机械系统，发现强机械驱动下其光致发光激发光谱出现对应悬臂转折点的双锐峰，且对微小机械失谐的敏感性极大增强，为质量传感等机械传感提供了有效机制。
Formulations of magnetic monopoles in a Hilbert-space formulation of quantum mechanics require Dirac's quantization condition of magnetic charge, which implies a large value that can easily be ruled out for elementary particles by standard atomic spectroscopy. However, an algebraic formulation of non-associative quantum mechanics is mathematically consistent with fractional magnetic charges of small values. Here, spectral properties in non-associative quantum mechanics are derived, applied to the ground state of hydrogen with a magnetically charged nucleus. The resulting energy leads to new st…
For quantum lattice systems with local interactions, the Lieb-Robinson bound acts as an alternative for the strict causality of relativistic systems and allows to prove many interesting results, in particular when the energy spectrum exhibits an energy gap. In this Letter, we show that for translation invariant systems, simultaneous eigenstates of energy and momentum with an eigenvalue that is separated from the rest of the spectrum in that momentum sector, can be arbitrarily well approximated by building a momentum superposition of a local operator acting on the ground state. The error decrea…
扫码添加微信好友，提出您的宝贵建议 👇
💡 备注请填写：网站反馈
发表机构由 AI 从论文文本抽取，如发现错误，欢迎反馈修正建议。