共查询到20条相似文献,搜索用时 31 毫秒
1.
G. Ya. Slepyan Y. D. Yerchak S. A. Maksimenko F. G. Bass 《Optics and Spectroscopy》2011,111(4):618-625
We theoretically investigate the spatial propagation of Rabi oscillations (Rabi waves) in one-dimensional inhomogeneous quantum
dot (QD) chain. QD-chain is modeled by the set of two-level quantum systems with tunnel coupling between neighboring QDs.
The space propagation of Rabi waves in the form of traveling waves and localized wave packets is considered. It is shown,
that the propagation of Rabi waves is accompanied by the transfer of the inversion and quantum correlations along the QD-chain
and by their reflection and mutual transformations at the spatial inhomogeneities of QE-chain. The effect is potentially applicable
in quantum nanooptics and quantum informatics. 相似文献
2.
G.Ya. Slepyan S.A. Maksimenko A.V. Magyarov A. Hoffmann D. Bimberg 《Superlattices and Microstructures》2004,36(4-6):773
The influence of local fields on the excitonic Rabi oscillations in an isolated, arbitrary shaped quantum dot (QD) has been theoretically investigated. QD interaction with both a classical electromagnetic field and quantum light has been considered. In the classical light, time harmonic and ultrashort pulse excitations are analyzed. The general formalism has been formulated for quantum light and applied to the case of a Fock qubit. Noticeable modification of the Rabi oscillation dynamics induced by the local fields is predicted to be observable in QDs exposed to both classical and quantum light. In particular, the bifurcation and anharmonism in the Rabi oscillations have been revealed under time harmonic excitation and a dependence of the Rabi oscillation period on the QD depolarization has been obtained. 相似文献
3.
Tunneling dynamics of Bose-Einstein condensates with higher-order interactions in optical lattice
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The nonlinear Landau-Zener tunneling and nonlinear Rabi oscillations of Bose-Einstein condensate (BEC) with higher-order atomic interaction between the Bloch bands in an accelerating optical lattice are discussed. Within the two-level model, the tunneling probability of BEC with higher-order atomic interaction between Bloch bands is obtained. We finds that the tunneling rate is closely related to the higher-order atomic interaction. Furthermore, the nonlinear Rabi oscillations of BEC with higher-order atomic interaction between the bands are discussed by imposing a periodic modulation on the level bias. Analytical expressions of the critical higher-order atomic interaction for suppressing/enhancing the Rabi oscillations are obtained. It is shown that the critical value strongly depends on the modulation parameters (i.e., the modulation amplitude and frequency) and the strength of periodic potential. 相似文献
4.
5.
The pump–probe experiment is typically used to study relaxation phenomena in nonlinear optical systems. Here we use it as a tool to study the phenomenon of anomalous Rabi oscillations in graphene that was predicted recently in single-layer graphene. Unlike conventional Rabi oscillations, anomalous Rabi oscillations are unique to graphene (and possibly to surface states of topological insulators (TIs)), attributable to the pseudospin (conventional spin for TI) degree of freedom and Dirac-fermion character of the graphene system. A pump pulse of a finite duration long enough to contain a large number of cycles induces a current density that oscillates with the frequency of the pump pulse. The amplitude associated with these fast oscillations is seen to exhibit much slower oscillations with a frequency given by \({ 2 \omega ^2_{\mathrm {R}} }/{ \omega } \) – the anomalous Rabi frequency, where ω R is the conventional Rabi frequency and ω is the frequency of the external pump field. This effect is easily probed by a probe pulse subsequent to the pump, where it manifests itself as periodic oscillations of the probe susceptibility as a function of pump duration at each probe frequency. Alternatively, it is also seen as an oscillatory function of the pump–probe delay with other variables remaining fixed. This period corresponds to the anomalous Rabi frequency. An analysis of the previously reported experimental data confirms the presence of anomalous Rabi oscillations in graphene. 相似文献
6.
The Rabi oscillations in two-component Bose-Einstein condensates with a coupling drive are studiedby means of a pair of bosonic operators. The coupling drive and initial phase difference will affect the amplitudeand the period of the Rabi oscillations. The Rabi oscillations will vanish in the evolution of the condensate densityfor some special initial phase differences (ψ = 0 or π). Our theory provides not only an analytical framework forquantitative predictions for two-component condensates, but also gives an intuitive understanding of some mysteriousfeatures observed in experiments and numerical. simulations. 相似文献
7.
《中国物理快报》2016,(3)
We experimentally demonstrate the relation of Raman coupling strength with the external bias magnetic field in degenerate Fermi gas of ~(40)K atoms.Two Raman lasers couple two Zeeman energy levels,whose energy splitting depends on the external bias magnetic field.The Raman coupling strength is determined by measuring the Rabi oscillation frequency.The characteristics of the Rabi oscillation is to be damped after several periods due to Fermi atoms in different momentum states oscillating with different Rabi frequencies.The experimental results show that the Raman coupling strength will decrease as the external bias magnetic field increases,which is in good agreement with the theoretical prediction. 相似文献
8.
Il'ichev E Oukhanski N Izmalkov A Wagner T Grajcar M Meyer HG Smirnov AY Maassen van den Brink A Amin MH Zagoskin AM 《Physical review letters》2003,91(9):097906
Under resonant irradiation, a quantum system can undergo coherent (Rabi) oscillations in time. We report evidence for such oscillations in a continuously observed three-Josephson-junction flux qubit, coupled to a high-quality tank circuit tuned to the Rabi frequency. In addition to simplicity, this method of Rabi spectroscopy enabled a long coherence time of about 2.5 micros, corresponding to an effective qubit quality factor approximately 7000. 相似文献
9.
《中国物理 B》2019,(1)
Motivated by experimental advances that the collective excitation of two Rydberg atoms was observed, we provide an elaborate theoretical study for the dynamical behavior of two-atom Rabi oscillations. In the large-intermediate-detuning case, the two-photon Rabi oscillation is found to be significantly affected by the strength of the interatomic van der Waals interaction. With a careful comparison of the exact numbers and values of the oscillation frequency, we propose a new way to determine the strength of excitation blockade, agreeing well with the previous universal criterion for full, partial, and no blockade regions. In the small-intermediate-detuning case, we find a blockade-like effect, but the collective enhancement factor is smaller than ~(1/2) due to the quantum interference of double optical transitions involving the intermediate state.Moreover, a fast two-photon Rabi oscillation in ns timescale is manifested by employing intense lasers with an intensity of ~MW/cm~2, offering a possibility of ultrafast control of quantum dynamics with Rydberg atoms. 相似文献
10.
We obtain pulse-driven Rabi oscillations guided by a generalization of the rotating-wave approximation to include, in the optical-Bloch equations, two-level systems with a time-varying transition energy. We achieve this by using chirped pulses with the central frequency given by the time-varying transition energy. Using this approach, we predict Rabi oscillations in intersubband transitions in a two-subband n-type modulation-doped quantum well by taking into account the time-dependent intersubband energy-gap renormalization due to depolarization-shift effects. We obtain Rabi oscillations for jpi (j=0,1,2, ) pulses in the presence of dephasing. 相似文献
11.
We investigate the reciprocal of the mean quantum Fisher information per particle (RMQFIP) and phase sensitivity of atomic Josephson junctions with a bosonic species confined by a double-well potential. Here we are focus on the Rabi oscillation energy’s influence on RMQFIP and phase sensitivity. The better quantum entanglement and phase sensitivity may be achieved by decreasing the Rabi oscillation energy. 相似文献
12.
通过求解全波矢布洛赫方程研究了两能级原子与飞秒超快激光脉冲的相互作用过程,计算了不同拉比频率取值下原子所受光学偶极力和粒子数布居随时间的演化情况,分析了光场失谐量对光学势分布情况的影响.研究发现:由飞秒激光场产生的横向光力的时间平均值并不等于零,而是随着拉比频率的增加呈现振荡的增大趋势;纵向光力的时间平均作用也并非是拉比频率的单调函数,而是随着拉比频率的增加呈现周期性的振荡分布特性;光学势的分布对光场的失谐量具有明显的依赖性,随着失谐量的变化,光学势的性质也随之发生了改变. 相似文献
13.
《Physics letters. A》2020,384(14):126287
Time evolution of pertinent operators in the Rabi Hamiltonian and its rotating wave approximation (RWA) version, the Jaynes-Cummings model (JCM), in the Heisenberg picture, gives systems of nonlinear differential equations (NDEs). Considering well localized atom, the mean field theory (MFT) was applied to replace the operators by equivalent expectation values. The Rabi model was reduced to a fourth orders NDE describing atoms position. Solution by the harmonic balance method (HBM) showed good accuracy and consistency to the numerical results, which introduces it as a useful tool in the quantum dynamics studies. The NDEs describing the JCM in the Heisenberg picture structurally prevent applying the MFT and shows inconsistency to the Ehrenfest's theorem, contrary to the Rabi model. 相似文献
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15.
We report observation and control of the spatial-spectral distributions of coherent, dynamic Rabi sideband radiation. The Rabi sidebands result from the interaction of a shaped picosecond probe laser of intensity 10(10) W cm(-2), with neutral excited atomic oxygen generated in a laser-induced microplasma. The spatial-spectral distribution is measured and compared for picosecond laser pulses having either an asymmetric temporal shape or a Gaussian temporal shape. The resulting spatial-spectral distributions are in quantitative agreement with theoretical predictions that account for the radial intensity distribution of the picosecond probe pulse. 相似文献
16.
We explore the possibility to generate new parity symmetry in the quantum Rabi model after a bias is introduced. In contrast to a mathematical treatment in a previous publication [J. Phys. A 46(2013) 265302], we consider a physically realistic method by involving an additional spin into the quantum Rabi model to couple with the original spin by an Ising interaction, and then the parity symmetry is broken as well as the scaling behavior of the ground state by introducing a bias. The rule can be found that the parity symmetry is broken by introducing a bias and then restored by adding new degrees of freedom. Experimental feasibility of realizing the models under discussion is investigated. 相似文献
17.
We consider a two-level system (TLS) with energy level separation plankvOmega0 inside a Josephson junction. The junction is shunted by a resistor R and is voltage V biased. If the TLS modulates the Josephson energy and/or is optically active, it is Rabi driven by the Josephson oscillations in the running phase regime near the resonance 2eV=plankvOmega0. The Rabi oscillations, in turn, translate into oscillations of current and voltage that can be detected in noise measurements. This effect provides an option to fully characterize the TLS inside Josephson junction and to find the TLS's contribution to the decoherence when the junction is used as a qubit. 相似文献
18.
We study theoretically the properties of a thin film of a semiconductor embedded in the interface of two kinds of single-negative materials. At some frequencies the structure with suitable size is equivalent to an effective (near) zero-index medium. The coupling of exciton resonance in the semiconductor and the interface mode in a zero-index medium leads to Rabi splitting. Compared with Rabi splitting observed in cavities, the splitting modes in zero-index media are robust against the scaling change of the length and direction of incident wave. 相似文献
19.
We have investigated the photon-field-shape effects on Rabi splitting energies in CuCl microcavities with HfO2/SiO2 distributed Bragg reflectors (DBRs). The CuCl active layer was prepared by vacuum deposition, while HfO2 and SiO2 layers were prepared by rf magnetron sputtering. The photon-field shape was tuned to a node-type or an antinode-type by changing the order of the refractive indices in the DBR. In order to control of the Rabi splitting energies, the active-layer thickness was changed from λ/12 to 9λ/20. In angle-resolved reflectance spectra at 10 K, three cavity polaritons resulting from the strong coupling between the Z3 and Z1,2 excitons and cavity photon were clearly detected. We estimated the energies of the exciton-photon interaction, the so-called vacuum Rabi splitting energies, from the analysis of the cavity polariton dispersions using a phenomenological Hamiltonian for the strong exciton-photon coupling. The active-layer-thickness dependence of the Rabi splitting energies are explained by a semi-quantitative analysis taking account of the overlap between the exciton and photon-field wave functions. We have demonstrated that the photon-field shape drastically affects the active-layer-thickness dependence of the Rabi splitting energies. 相似文献
20.
The out-of-time-order correlators (OTOCs) is used to study the quantum phase transitions (QPTs) between the normal phase and the superradiant phase in the Rabi and few-body Dicke models with large frequency ratio of the atomic level splitting to the single-mode electromagnetic radiation field frequency. The focus is on the OTOC thermally averaged with infinite temperature, which is an experimentally feasible quantity. It is shown that the critical points can be identified by long-time averaging of the OTOC via observing its local minimum behavior. More importantly, the scaling laws of the OTOC for QPTs are revealed by studying the experimentally accessible conditions with finite frequency ratio and finite number of atoms in the studied models. The critical exponents extracted from the scaling laws of OTOC indicate that the QPTs in the Rabi and Dicke models belong to the same universality class. 相似文献